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authorErik Johnston <erik@matrix.org>2022-08-24 09:58:29 +0100
committerGitHub <noreply@github.com>2022-08-24 09:58:29 +0100
commitcbb157548676865793f39b4da0b7f3fa5ee01058 (patch)
tree77ff41ddcb9b01938b4efdd109cf90981c86a23e
parentNewsfile (diff)
parentInstrument `_check_sigs_and_hash_and_fetch` to trace time spent in child conc... (diff)
downloadsynapse-github/erikj/less_state_membership.tar.xz
Merge branch 'develop' into erikj/less_state_membership github/erikj/less_state_membership erikj/less_state_membership
-rw-r--r--.github/workflows/latest_deps.yml37
-rw-r--r--.github/workflows/tests.yml41
-rw-r--r--CHANGES.md283
-rw-r--r--README.rst450
-rw-r--r--changelog.d/12942.misc1
-rw-r--r--changelog.d/12943.misc1
-rw-r--r--changelog.d/12967.removal1
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-rw-r--r--changelog.d/13231.doc1
-rw-r--r--changelog.d/13233.doc1
-rw-r--r--changelog.d/13239.removal1
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-rw-r--r--changelog.d/13263.bugfix1
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-rw-r--r--changelog.d/13326.removal1
-rw-r--r--changelog.d/13328.misc1
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-rw-r--r--changelog.d/13588.misc1
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-rw-r--r--changelog.d/13592.misc1
-rw-r--r--changelog.d/13600.misc1
-rw-r--r--changelog.d/13602.doc1
-rw-r--r--contrib/grafana/synapse.json4500
-rw-r--r--debian/changelog42
-rw-r--r--docker/Dockerfile27
-rw-r--r--docker/Dockerfile-workers94
-rw-r--r--docker/README-testing.md4
-rw-r--r--docker/README.md2
-rw-r--r--docker/complement/Dockerfile1
-rw-r--r--docker/conf-workers/supervisord.conf.j22
-rw-r--r--docs/admin_api/register_api.md21
-rw-r--r--docs/admin_api/rooms.md7
-rw-r--r--docs/admin_api/user_admin_api.md7
-rw-r--r--docs/auth_chain_difference_algorithm.md51
-rw-r--r--docs/message_retention_policies.md3
-rw-r--r--docs/modules/password_auth_provider_callbacks.md4
-rw-r--r--docs/openid.md4
-rw-r--r--docs/reverse_proxy.md53
-rw-r--r--docs/sso_mapping_providers.md14
-rw-r--r--docs/templates.md2
-rw-r--r--docs/upgrade.md33
-rw-r--r--docs/usage/administration/admin_api/README.md3
-rw-r--r--docs/usage/administration/admin_api/registration_tokens.md6
-rw-r--r--docs/usage/administration/admin_faq.md90
-rw-r--r--docs/usage/configuration/config_documentation.md461
-rw-r--r--mypy.ini5
-rw-r--r--poetry.lock114
-rw-r--r--pyproject.toml5
-rwxr-xr-xscripts-dev/check_pydantic_models.py425
-rwxr-xr-xscripts-dev/complement.sh1
-rwxr-xr-xscripts-dev/lint.sh1
-rwxr-xr-xscripts-dev/release.py162
-rw-r--r--synapse/api/auth.py221
-rw-r--r--synapse/api/constants.py11
-rw-r--r--synapse/api/errors.py58
-rw-r--r--synapse/api/ratelimiting.py6
-rw-r--r--synapse/api/room_versions.py38
-rw-r--r--synapse/app/admin_cmd.py28
-rw-r--r--synapse/app/generic_worker.py43
-rw-r--r--synapse/app/homeserver.py5
-rw-r--r--synapse/config/account_validity.py2
-rw-r--r--synapse/config/emailconfig.py9
-rw-r--r--synapse/config/experimental.py9
-rw-r--r--synapse/config/ratelimiting.py42
-rw-r--r--synapse/config/registration.py1
-rw-r--r--synapse/config/sso.py2
-rw-r--r--synapse/crypto/event_signing.py2
-rw-r--r--synapse/event_auth.py62
-rw-r--r--synapse/events/snapshot.py7
-rw-r--r--synapse/events/spamcheck.py2
-rw-r--r--synapse/events/utils.py2
-rw-r--r--synapse/federation/federation_base.py22
-rw-r--r--synapse/federation/federation_client.py62
-rw-r--r--synapse/federation/federation_server.py30
-rw-r--r--synapse/federation/transport/server/_base.py2
-rw-r--r--synapse/handlers/auth.py19
-rw-r--r--synapse/handlers/device.py17
-rw-r--r--synapse/handlers/directory.py24
-rw-r--r--synapse/handlers/e2e_keys.py16
-rw-r--r--synapse/handlers/e2e_room_keys.py4
-rw-r--r--synapse/handlers/federation.py127
-rw-r--r--synapse/handlers/federation_event.py399
-rw-r--r--synapse/handlers/initial_sync.py17
-rw-r--r--synapse/handlers/message.py67
-rw-r--r--synapse/handlers/pagination.py4
-rw-r--r--synapse/handlers/presence.py112
-rw-r--r--synapse/handlers/receipts.py36
-rw-r--r--synapse/handlers/register.py15
-rw-r--r--synapse/handlers/relations.py7
-rw-r--r--synapse/handlers/room.py63
-rw-r--r--synapse/handlers/room_list.py2
-rw-r--r--synapse/handlers/room_member.py75
-rw-r--r--synapse/handlers/room_summary.py5
-rw-r--r--synapse/handlers/send_email.py36
-rw-r--r--synapse/handlers/sync.py390
-rw-r--r--synapse/handlers/typing.py23
-rw-r--r--synapse/http/server.py18
-rw-r--r--synapse/http/servlet.py25
-rw-r--r--synapse/http/site.py2
-rw-r--r--synapse/logging/opentracing.py232
-rw-r--r--synapse/metrics/background_process_metrics.py2
-rw-r--r--synapse/module_api/__init__.py83
-rw-r--r--synapse/push/baserules.py529
-rw-r--r--synapse/push/bulk_push_rule_evaluator.py37
-rw-r--r--synapse/push/clientformat.py68
-rw-r--r--synapse/push/push_rule_evaluator.py27
-rw-r--r--synapse/replication/slave/storage/_base.py58
-rw-r--r--synapse/replication/slave/storage/account_data.py22
-rw-r--r--synapse/replication/slave/storage/appservice.py25
-rw-r--r--synapse/replication/slave/storage/deviceinbox.py20
-rw-r--r--synapse/replication/slave/storage/devices.py3
-rw-r--r--synapse/replication/slave/storage/directory.py21
-rw-r--r--synapse/replication/slave/storage/events.py3
-rw-r--r--synapse/replication/slave/storage/filtering.py5
-rw-r--r--synapse/replication/slave/storage/profile.py20
-rw-r--r--synapse/replication/slave/storage/push_rule.py1
-rw-r--r--synapse/replication/slave/storage/pushers.py3
-rw-r--r--synapse/replication/slave/storage/receipts.py22
-rw-r--r--synapse/replication/slave/storage/registration.py21
-rw-r--r--synapse/replication/tcp/client.py5
-rw-r--r--synapse/res/templates/account_previously_renewed.html13
-rw-r--r--synapse/res/templates/account_renewed.html13
-rw-r--r--synapse/res/templates/add_threepid.html11
-rw-r--r--synapse/res/templates/add_threepid_failure.html15
-rw-r--r--synapse/res/templates/add_threepid_success.html14
-rw-r--r--synapse/res/templates/auth_success.html4
-rw-r--r--synapse/res/templates/invalid_token.html13
-rw-r--r--synapse/res/templates/notice_expiry.html2
-rw-r--r--synapse/res/templates/notif_mail.html2
-rw-r--r--synapse/res/templates/password_reset.html7
-rw-r--r--synapse/res/templates/password_reset_confirmation.html8
-rw-r--r--synapse/res/templates/password_reset_failure.html8
-rw-r--r--synapse/res/templates/password_reset_success.html7
-rw-r--r--synapse/res/templates/recaptcha.html4
-rw-r--r--synapse/res/templates/registration.html7
-rw-r--r--synapse/res/templates/registration_failure.html7
-rw-r--r--synapse/res/templates/registration_success.html8
-rw-r--r--synapse/res/templates/registration_token.html6
-rw-r--r--synapse/res/templates/sso_account_deactivated.html4
-rw-r--r--synapse/res/templates/sso_auth_account_details.html5
-rw-r--r--synapse/res/templates/sso_auth_bad_user.html3
-rw-r--r--synapse/res/templates/sso_auth_confirm.html3
-rw-r--r--synapse/res/templates/sso_auth_success.html3
-rw-r--r--synapse/res/templates/sso_error.html3
-rw-r--r--synapse/res/templates/sso_login_idp_picker.html2
-rw-r--r--synapse/res/templates/sso_new_user_consent.html3
-rw-r--r--synapse/res/templates/sso_redirect_confirm.html3
-rw-r--r--synapse/res/templates/terms.html4
-rw-r--r--synapse/rest/admin/_base.py10
-rw-r--r--synapse/rest/admin/media.py6
-rw-r--r--synapse/rest/admin/rooms.py13
-rw-r--r--synapse/rest/admin/users.py15
-rw-r--r--synapse/rest/client/account.py134
-rw-r--r--synapse/rest/client/devices.py27
-rw-r--r--synapse/rest/client/keys.py7
-rw-r--r--synapse/rest/client/models.py69
-rw-r--r--synapse/rest/client/notifications.py7
-rw-r--r--synapse/rest/client/profile.py4
-rw-r--r--synapse/rest/client/read_marker.py8
-rw-r--r--synapse/rest/client/receipts.py10
-rw-r--r--synapse/rest/client/register.py7
-rw-r--r--synapse/rest/client/room.py100
-rw-r--r--synapse/rest/client/sendtodevice.py3
-rw-r--r--synapse/rest/client/versions.py5
-rw-r--r--synapse/rest/models.py23
-rw-r--r--synapse/server_notices/server_notices_manager.py2
-rw-r--r--synapse/state/__init__.py107
-rw-r--r--synapse/state/v2.py12
-rw-r--r--synapse/static/client/login/index.html3
-rw-r--r--synapse/static/client/register/index.html3
-rw-r--r--synapse/storage/_base.py4
-rw-r--r--synapse/storage/controllers/persist_events.py30
-rw-r--r--synapse/storage/controllers/state.py57
-rw-r--r--synapse/storage/database.py8
-rw-r--r--synapse/storage/databases/main/__init__.py29
-rw-r--r--synapse/storage/databases/main/account_data.py3
-rw-r--r--synapse/storage/databases/main/cache.py26
-rw-r--r--synapse/storage/databases/main/deviceinbox.py2
-rw-r--r--synapse/storage/databases/main/devices.py4
-rw-r--r--synapse/storage/databases/main/end_to_end_keys.py6
-rw-r--r--synapse/storage/databases/main/event_federation.py9
-rw-r--r--synapse/storage/databases/main/event_push_actions.py471
-rw-r--r--synapse/storage/databases/main/events.py4
-rw-r--r--synapse/storage/databases/main/events_worker.py193
-rw-r--r--synapse/storage/databases/main/push_rule.py127
-rw-r--r--synapse/storage/databases/main/receipts.py2
-rw-r--r--synapse/storage/databases/main/registration.py2
-rw-r--r--synapse/storage/databases/main/relations.py6
-rw-r--r--synapse/storage/databases/main/room.py8
-rw-r--r--synapse/storage/databases/main/roommember.py185
-rw-r--r--synapse/storage/databases/main/state.py13
-rw-r--r--synapse/storage/databases/main/stream.py2
-rw-r--r--synapse/storage/databases/state/store.py9
-rw-r--r--synapse/storage/state.py9
-rw-r--r--synapse/storage/util/partial_state_events_tracker.py3
-rw-r--r--synapse/streams/events.py2
-rw-r--r--synapse/util/caches/deferred_cache.py346
-rw-r--r--synapse/util/caches/descriptors.py115
-rw-r--r--synapse/util/caches/dictionary_cache.py218
-rw-r--r--synapse/util/caches/lrucache.py107
-rw-r--r--synapse/util/caches/treecache.py41
-rw-r--r--synapse/util/ratelimitutils.py117
-rw-r--r--synapse/visibility.py6
-rw-r--r--tests/api/test_auth.py8
-rw-r--r--tests/events/test_presence_router.py4
-rw-r--r--tests/federation/test_complexity.py5
-rw-r--r--tests/federation/transport/test_knocking.py5
-rw-r--r--tests/handlers/test_deactivate_account.py51
-rw-r--r--tests/handlers/test_directory.py12
-rw-r--r--tests/handlers/test_federation.py136
-rw-r--r--tests/handlers/test_message.py2
-rw-r--r--tests/handlers/test_password_providers.py11
-rw-r--r--tests/handlers/test_receipts.py58
-rw-r--r--tests/handlers/test_register.py7
-rw-r--r--tests/handlers/test_room_member.py7
-rw-r--r--tests/handlers/test_send_email.py57
-rw-r--r--tests/handlers/test_typing.py8
-rw-r--r--tests/http/server/_base.py3
-rw-r--r--tests/logging/test_opentracing.py113
-rw-r--r--tests/module_api/test_api.py106
-rw-r--r--tests/replication/_base.py90
-rw-r--r--tests/replication/slave/storage/test_account_data.py42
-rw-r--r--tests/replication/tcp/test_handler.py4
-rw-r--r--tests/replication/test_sharded_event_persister.py7
-rw-r--r--tests/rest/admin/test_admin.py31
-rw-r--r--tests/rest/admin/test_background_updates.py29
-rw-r--r--tests/rest/admin/test_device.py77
-rw-r--r--tests/rest/admin/test_event_reports.py142
-rw-r--r--tests/rest/admin/test_federation.py73
-rw-r--r--tests/rest/admin/test_media.py166
-rw-r--r--tests/rest/admin/test_registration_tokens.py201
-rw-r--r--tests/rest/admin/test_room.py232
-rw-r--r--tests/rest/admin/test_server_notice.py93
-rw-r--r--tests/rest/admin/test_statistics.py99
-rw-r--r--tests/rest/admin/test_user.py541
-rw-r--r--tests/rest/admin/test_username_available.py17
-rw-r--r--tests/rest/client/test_account.py10
-rw-r--r--tests/rest/client/test_filter.py14
-rw-r--r--tests/rest/client/test_login.py127
-rw-r--r--tests/rest/client/test_models.py53
-rw-r--r--tests/rest/client/test_redactions.py4
-rw-r--r--tests/rest/client/test_register.py94
-rw-r--r--tests/rest/client/test_relations.py6
-rw-r--r--tests/rest/client/test_report_event.py4
-rw-r--r--tests/rest/client/test_retention.py4
-rw-r--r--tests/rest/client/test_rooms.py7
-rw-r--r--tests/rest/client/test_shadow_banned.py6
-rw-r--r--tests/rest/client/test_sync.py79
-rw-r--r--tests/rest/client/test_third_party_rules.py27
-rw-r--r--tests/rest/client/utils.py28
-rw-r--r--tests/rest/test_health.py4
-rw-r--r--tests/rest/test_well_known.py12
-rw-r--r--tests/server.py25
-rw-r--r--tests/server_notices/test_resource_limits_server_notices.py9
-rw-r--r--tests/storage/test_event_push_actions.py15
-rw-r--r--tests/storage/test_events.py7
-rw-r--r--tests/storage/test_receipts.py (renamed from tests/replication/slave/storage/test_receipts.py)107
-rw-r--r--tests/storage/test_roommember.py70
-rw-r--r--tests/storage/test_state.py10
-rw-r--r--tests/test_server.py26
-rw-r--r--tests/test_state.py2
-rw-r--r--tests/test_terms_auth.py6
-rw-r--r--tests/unittest.py101
-rw-r--r--tests/util/test_dict_cache.py35
306 files changed, 10606 insertions, 6035 deletions
diff --git a/.github/workflows/latest_deps.yml b/.github/workflows/latest_deps.yml
index c537a5a60f..f263cf612d 100644
--- a/.github/workflows/latest_deps.yml
+++ b/.github/workflows/latest_deps.yml
@@ -135,11 +135,42 @@ jobs:
             /logs/**/*.log*
 
 
-  # TODO: run complement (as with twisted trunk, see #12473).
+  complement:
+    if: "${{ !failure() && !cancelled() }}"
+    runs-on: ubuntu-latest
+
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - arrangement: monolith
+            database: SQLite
+
+          - arrangement: monolith
+            database: Postgres
+
+          - arrangement: workers
+            database: Postgres
+
+    steps:
+      - name: Run actions/checkout@v2 for synapse
+        uses: actions/checkout@v2
+        with:
+          path: synapse
+
+      - name: Prepare Complement's Prerequisites
+        run: synapse/.ci/scripts/setup_complement_prerequisites.sh
+
+      - run: |
+          set -o pipefail
+          TEST_ONLY_IGNORE_POETRY_LOCKFILE=1 POSTGRES=${{ (matrix.database == 'Postgres') && 1 || '' }} WORKERS=${{ (matrix.arrangement == 'workers') && 1 || '' }} COMPLEMENT_DIR=`pwd`/complement synapse/scripts-dev/complement.sh -json 2>&1 | gotestfmt
+        shell: bash
+        name: Run Complement Tests
 
-  # open an issue if the build fails, so we know about it.
+  # Open an issue if the build fails, so we know about it.
+  # Only do this if we're not experimenting with this action in a PR.
   open-issue:
-    if: failure()
+    if: "failure() && github.event_name != 'push' && github.event_name != 'pull_request'"
     needs:
       # TODO: should mypy be included here? It feels more brittle than the other two.
       - mypy
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index c8b033e8a4..144cb9ffaa 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -53,10 +53,22 @@ jobs:
         env:
           PULL_REQUEST_NUMBER: ${{ github.event.number }}
 
+  lint-pydantic:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          ref: ${{ github.event.pull_request.head.sha }}
+          fetch-depth: 0
+      - uses: matrix-org/setup-python-poetry@v1
+        with:
+          extras: "all"
+      - run: poetry run scripts-dev/check_pydantic_models.py
+
   # Dummy step to gate other tests on without repeating the whole list
   linting-done:
     if: ${{ !cancelled() }} # Run this even if prior jobs were skipped
-    needs: [lint, lint-crlf, lint-newsfile, check-sampleconfig, check-schema-delta]
+    needs: [lint, lint-crlf, lint-newsfile, lint-pydantic, check-sampleconfig, check-schema-delta]
     runs-on: ubuntu-latest
     steps:
       - run: "true"
@@ -328,29 +340,8 @@ jobs:
           - arrangement: monolith
             database: Postgres
 
-    steps:
-      - name: Run actions/checkout@v2 for synapse
-        uses: actions/checkout@v2
-        with:
-          path: synapse
-
-      - name: Prepare Complement's Prerequisites
-        run: synapse/.ci/scripts/setup_complement_prerequisites.sh
-
-      - run: |
-          set -o pipefail
-          POSTGRES=${{ (matrix.database == 'Postgres') && 1 || '' }} WORKERS=${{ (matrix.arrangement == 'workers') && 1 || '' }} COMPLEMENT_DIR=`pwd`/complement synapse/scripts-dev/complement.sh -json 2>&1 | gotestfmt
-        shell: bash
-        name: Run Complement Tests
-
-  # XXX When complement with workers is stable, move this back into the standard
-  #     "complement" matrix above.
-  #
-  # See https://github.com/matrix-org/synapse/issues/13161
-  complement-workers:
-    if: "${{ !failure() && !cancelled() }}"
-    needs: linting-done
-    runs-on: ubuntu-latest
+          - arrangement: workers
+            database: Postgres
 
     steps:
       - name: Run actions/checkout@v2 for synapse
@@ -363,7 +354,7 @@ jobs:
 
       - run: |
           set -o pipefail
-          POSTGRES=1 WORKERS=1 COMPLEMENT_DIR=`pwd`/complement synapse/scripts-dev/complement.sh -json 2>&1 | gotestfmt
+          POSTGRES=${{ (matrix.database == 'Postgres') && 1 || '' }} WORKERS=${{ (matrix.arrangement == 'workers') && 1 || '' }} COMPLEMENT_DIR=`pwd`/complement synapse/scripts-dev/complement.sh -json 2>&1 | gotestfmt
         shell: bash
         name: Run Complement Tests
 
diff --git a/CHANGES.md b/CHANGES.md
index 1d123abc19..14fafc260d 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,7 +1,284 @@
-Synapse vNext
-=============
+Synapse 1.66.0rc1 (2022-08-23)
+==============================
+
+This release removes the ability for homeservers to delegate email ownership
+verification and password reset confirmation to identity servers. This removal
+was originally planned for Synapse 1.64, but was later deferred until now.
+
+See the [upgrade notes](https://matrix-org.github.io/synapse/v1.66/upgrade.html#upgrading-to-v1660) for more details.
+
+Features
+--------
+
+- Improve validation of request bodies for the following client-server API endpoints: [`/account/password`](https://spec.matrix.org/v1.3/client-server-api/#post_matrixclientv3accountpassword), [`/account/password/email/requestToken`](https://spec.matrix.org/v1.3/client-server-api/#post_matrixclientv3accountpasswordemailrequesttoken), [`/account/deactivate`](https://spec.matrix.org/v1.3/client-server-api/#post_matrixclientv3accountdeactivate) and [`/account/3pid/email/requestToken`](https://spec.matrix.org/v1.3/client-server-api/#post_matrixclientv3account3pidemailrequesttoken). ([\#13188](https://github.com/matrix-org/synapse/issues/13188), [\#13563](https://github.com/matrix-org/synapse/issues/13563))
+- Add forgotten status to [Room Details Admin API](https://matrix-org.github.io/synapse/latest/admin_api/rooms.html#room-details-api). ([\#13503](https://github.com/matrix-org/synapse/issues/13503))
+- Add an experimental implementation for [MSC3852 (Expose user agents on `Device`)](https://github.com/matrix-org/matrix-spec-proposals/pull/3852). ([\#13549](https://github.com/matrix-org/synapse/issues/13549))
+- Add `org.matrix.msc2716v4` experimental room version with updated content fields. Part of [MSC2716 (Importing history)](https://github.com/matrix-org/matrix-spec-proposals/pull/2716).  ([\#13551](https://github.com/matrix-org/synapse/issues/13551))
+- Add support for compression to federation responses. ([\#13537](https://github.com/matrix-org/synapse/issues/13537))
+- Improve performance of sending messages in rooms with thousands of local users. ([\#13522](https://github.com/matrix-org/synapse/issues/13522), [\#13547](https://github.com/matrix-org/synapse/issues/13547))
+
+
+Bugfixes
+--------
+
+- Faster room joins: make `/joined_members` block whilst the room is partial stated. ([\#13514](https://github.com/matrix-org/synapse/issues/13514))
+- Fix a bug introduced in Synapse 1.21.0 where the [`/event_reports` Admin API](https://matrix-org.github.io/synapse/develop/admin_api/event_reports.html) could return a total count which was larger than the number of results you can actually query for. ([\#13525](https://github.com/matrix-org/synapse/issues/13525))
+- Fix a bug introduced in Synapse 1.52.0 where sending server notices fails if `max_avatar_size` or `allowed_avatar_mimetypes` is set and not `system_mxid_avatar_url`. ([\#13566](https://github.com/matrix-org/synapse/issues/13566))
+- Fix a bug where the `opentracing.force_tracing_for_users` config option would not apply to [`/sendToDevice`](https://spec.matrix.org/v1.3/client-server-api/#put_matrixclientv3sendtodeviceeventtypetxnid) and [`/keys/upload`](https://spec.matrix.org/v1.3/client-server-api/#post_matrixclientv3keysupload) requests. ([\#13574](https://github.com/matrix-org/synapse/issues/13574))
+
+
+Improved Documentation
+----------------------
+
+- Add `openssl` example for generating registration HMAC digest. ([\#13472](https://github.com/matrix-org/synapse/issues/13472))
+- Tidy up Synapse's README. ([\#13491](https://github.com/matrix-org/synapse/issues/13491))
+- Document that event purging related to the `redaction_retention_period` config option is executed only every 5 minutes. ([\#13492](https://github.com/matrix-org/synapse/issues/13492))
+- Add a warning to retention documentation regarding the possibility of database corruption. ([\#13497](https://github.com/matrix-org/synapse/issues/13497))
+- Document that the `DOCKER_BUILDKIT=1` flag is needed to build the docker image. ([\#13515](https://github.com/matrix-org/synapse/issues/13515))
+- Add missing links in `user_consent` section of configuration manual. ([\#13536](https://github.com/matrix-org/synapse/issues/13536))
+- Fix the doc and some warnings that were referring to the nonexistent `custom_templates_directory` setting (instead of `custom_template_directory`). ([\#13538](https://github.com/matrix-org/synapse/issues/13538))
+
+
+Deprecations and Removals
+-------------------------
+
+- Remove the ability for homeservers to delegate email ownership verification
+  and password reset confirmation to identity servers. See [upgrade notes](https://matrix-org.github.io/synapse/v1.66/upgrade.html#upgrading-to-v1660) for more details.
+
+Internal Changes
+----------------
+
+### Faster room joins
+
+- Update the rejected state of events during de-partial-stating. ([\#13459](https://github.com/matrix-org/synapse/issues/13459))
+- Avoid blocking lazy-loading `/sync`s during partial joins due to remote memberships. Pull remote memberships from auth events instead of the room state. ([\#13477](https://github.com/matrix-org/synapse/issues/13477))
+- Refuse to start when faster joins is enabled on a deployment with workers, since worker configurations are not currently supported. ([\#13531](https://github.com/matrix-org/synapse/issues/13531))
+
+### Metrics and tracing
+
+- Allow use of both `@trace` and `@tag_args` stacked on the same function. ([\#13453](https://github.com/matrix-org/synapse/issues/13453))
+- Instrument the federation/backfill part of `/messages` for understandable traces in Jaeger. ([\#13489](https://github.com/matrix-org/synapse/issues/13489))
+- Instrument `FederationStateIdsServlet` (`/state_ids`) for understandable traces in Jaeger. ([\#13499](https://github.com/matrix-org/synapse/issues/13499), [\#13554](https://github.com/matrix-org/synapse/issues/13554))
+- Track HTTP response times over 10 seconds from `/messages` (`synapse_room_message_list_rest_servlet_response_time_seconds`). ([\#13533](https://github.com/matrix-org/synapse/issues/13533))
+- Add metrics to track how the rate limiter is affecting requests (sleep/reject). ([\#13534](https://github.com/matrix-org/synapse/issues/13534), [\#13541](https://github.com/matrix-org/synapse/issues/13541))
+- Add metrics to time how long it takes us to do backfill processing (`synapse_federation_backfill_processing_before_time_seconds`, `synapse_federation_backfill_processing_after_time_seconds`). ([\#13535](https://github.com/matrix-org/synapse/issues/13535), [\#13584](https://github.com/matrix-org/synapse/issues/13584))
+- Add metrics to track rate limiter queue timing (`synapse_rate_limit_queue_wait_time_seconds`). ([\#13544](https://github.com/matrix-org/synapse/issues/13544))
+- Update metrics to track `/messages` response time by room size. ([\#13545](https://github.com/matrix-org/synapse/issues/13545))
+
+### Everything else
+
+- Refactor methods in `synapse.api.auth.Auth` to use `Requester` objects everywhere instead of user IDs. ([\#13024](https://github.com/matrix-org/synapse/issues/13024))
+- Clean-up tests for notifications. ([\#13471](https://github.com/matrix-org/synapse/issues/13471))
+- Add some miscellaneous comments to document sync, especially around `compute_state_delta`. ([\#13474](https://github.com/matrix-org/synapse/issues/13474))
+- Use literals in place of `HTTPStatus` constants in tests. ([\#13479](https://github.com/matrix-org/synapse/issues/13479), [\#13488](https://github.com/matrix-org/synapse/issues/13488))
+- Add comments about how event push actions are rotated. ([\#13485](https://github.com/matrix-org/synapse/issues/13485))
+- Modify HTML template content to better support mobile devices' screen sizes. ([\#13493](https://github.com/matrix-org/synapse/issues/13493))
+- Add a linter script which will reject non-strict types in Pydantic models. ([\#13502](https://github.com/matrix-org/synapse/issues/13502))
+- Reduce the number of tests using legacy TCP replication. ([\#13543](https://github.com/matrix-org/synapse/issues/13543))
+- Allow specifying additional request fields when using the `HomeServerTestCase.login` helper method. ([\#13549](https://github.com/matrix-org/synapse/issues/13549))
+- Make `HomeServerTestCase` load any configured homeserver modules automatically. ([\#13558](https://github.com/matrix-org/synapse/issues/13558))
+
+
+Synapse 1.65.0 (2022-08-16)
+===========================
+
+No significant changes since 1.65.0rc2.
+
+
+Synapse 1.65.0rc2 (2022-08-11)
+==============================
+
+Internal Changes
+----------------
+
+- Revert 'Remove the unspecced `room_id` field in the `/hierarchy` response. ([\#13365](https://github.com/matrix-org/synapse/issues/13365))' to give more time for clients to update. ([\#13501](https://github.com/matrix-org/synapse/issues/13501))
+
+
+Synapse 1.65.0rc1 (2022-08-09)
+==============================
+
+Features
+--------
+
+- Add support for stable prefixes for [MSC2285 (private read receipts)](https://github.com/matrix-org/matrix-spec-proposals/pull/2285). ([\#13273](https://github.com/matrix-org/synapse/issues/13273))
+- Add new unstable error codes `ORG.MATRIX.MSC3848.ALREADY_JOINED`, `ORG.MATRIX.MSC3848.NOT_JOINED`, and `ORG.MATRIX.MSC3848.INSUFFICIENT_POWER` described in [MSC3848](https://github.com/matrix-org/matrix-spec-proposals/pull/3848). ([\#13343](https://github.com/matrix-org/synapse/issues/13343))
+- Use stable prefixes for [MSC3827](https://github.com/matrix-org/matrix-spec-proposals/pull/3827). ([\#13370](https://github.com/matrix-org/synapse/issues/13370))
+- Add a new module API method to translate a room alias into a room ID. ([\#13428](https://github.com/matrix-org/synapse/issues/13428))
+- Add a new module API method to create a room. ([\#13429](https://github.com/matrix-org/synapse/issues/13429))
+- Add remote join capability to the module API's `update_room_membership` method (in a backwards compatible manner). ([\#13441](https://github.com/matrix-org/synapse/issues/13441))
+
+
+Bugfixes
+--------
+
+- Update the version of the LDAP3 auth provider module included in the `matrixdotorg/synapse` DockerHub images and the Debian packages hosted on packages.matrix.org to 0.2.2. This version fixes a regression in the module. ([\#13470](https://github.com/matrix-org/synapse/issues/13470))
+- Fix a bug introduced in Synapse v1.41.0 where the `/hierarchy` API returned non-standard information (a `room_id` field under each entry in `children_state`) (this was reverted in v1.65.0rc2, see changelog notes above). ([\#13365](https://github.com/matrix-org/synapse/issues/13365))
+- Fix a bug introduced in Synapse 0.24.0 that would respond with the wrong error status code to `/joined_members` requests when the requester is not a current member of the room. Contributed by @andrewdoh. ([\#13374](https://github.com/matrix-org/synapse/issues/13374))
+- Fix bug in handling of typing events for appservices. Contributed by Nick @ Beeper (@fizzadar). ([\#13392](https://github.com/matrix-org/synapse/issues/13392))
+- Fix a bug introduced in Synapse 1.57.0 where rooms listed in `exclude_rooms_from_sync` in the configuration file would not be properly excluded from incremental syncs. ([\#13408](https://github.com/matrix-org/synapse/issues/13408))
+- Fix a bug in the experimental faster-room-joins support which could cause it to get stuck in an infinite loop. ([\#13353](https://github.com/matrix-org/synapse/issues/13353))
+- Faster room joins: fix a bug which caused rejected events to become un-rejected during state syncing. ([\#13413](https://github.com/matrix-org/synapse/issues/13413))
+- Faster room joins: fix error when running out of servers to sync partial state with, so that Synapse raises the intended error instead. ([\#13432](https://github.com/matrix-org/synapse/issues/13432))
+
+
+Updates to the Docker image
+---------------------------
+
+- Make Docker images build on armv7 by installing cryptography dependencies in the 'requirements' stage. Contributed by Jasper Spaans. ([\#13372](https://github.com/matrix-org/synapse/issues/13372))
+
+
+Improved Documentation
+----------------------
+
+- Update the 'registration tokens' page to acknowledge that the relevant MSC was merged into version 1.2 of the Matrix specification. Contributed by @moan0s. ([\#11897](https://github.com/matrix-org/synapse/issues/11897))
+- Document which HTTP resources support gzip compression. ([\#13221](https://github.com/matrix-org/synapse/issues/13221))
+- Add steps describing how to elevate an existing user to administrator by manipulating the database. ([\#13230](https://github.com/matrix-org/synapse/issues/13230))
+- Fix wrong headline for `url_preview_accept_language` in documentation. ([\#13437](https://github.com/matrix-org/synapse/issues/13437))
+- Remove redundant 'Contents' section from the Configuration Manual. Contributed by @dklimpel. ([\#13438](https://github.com/matrix-org/synapse/issues/13438))
+- Update documentation for config setting `macaroon_secret_key`. ([\#13443](https://github.com/matrix-org/synapse/issues/13443))
+- Update outdated information on `sso_mapping_providers` documentation. ([\#13449](https://github.com/matrix-org/synapse/issues/13449))
+- Fix example code in module documentation of `password_auth_provider_callbacks`. ([\#13450](https://github.com/matrix-org/synapse/issues/13450))
+- Make the configuration for the cache clearer. ([\#13481](https://github.com/matrix-org/synapse/issues/13481))
+
+
+Internal Changes
+----------------
+
+- Extend the release script to automatically push a new SyTest branch, rather than having that be a manual process. ([\#12978](https://github.com/matrix-org/synapse/issues/12978))
+- Make minor clarifications to the error messages given when we fail to join a room via any server. ([\#13160](https://github.com/matrix-org/synapse/issues/13160))
+- Enable Complement CI tests in the 'latest deps' test run. ([\#13213](https://github.com/matrix-org/synapse/issues/13213))
+- Fix long-standing bugged logic which was never hit in `get_pdu` asking every remote destination even after it finds an event. ([\#13346](https://github.com/matrix-org/synapse/issues/13346))
+- Faster room joins: avoid blocking when pulling events with partially missing prev events. ([\#13355](https://github.com/matrix-org/synapse/issues/13355))
+- Instrument `/messages` for understandable traces in Jaeger. ([\#13368](https://github.com/matrix-org/synapse/issues/13368))
+- Remove an unused argument to `get_relations_for_event`. ([\#13383](https://github.com/matrix-org/synapse/issues/13383))
+- Add a `merge-back` command to the release script, which automates merging the correct branches after a release. ([\#13393](https://github.com/matrix-org/synapse/issues/13393))
+- Adding missing type hints to tests. ([\#13397](https://github.com/matrix-org/synapse/issues/13397))
+- Faster Room Joins: don't leave a stuck room partial state flag if the join fails. ([\#13403](https://github.com/matrix-org/synapse/issues/13403))
+- Refactor `_resolve_state_at_missing_prevs` to compute an `EventContext` instead. ([\#13404](https://github.com/matrix-org/synapse/issues/13404), [\#13431](https://github.com/matrix-org/synapse/issues/13431))
+- Faster Room Joins: prevent Synapse from answering federated join requests for a room which it has not fully joined yet. ([\#13416](https://github.com/matrix-org/synapse/issues/13416))
+- Re-enable running Complement tests against Synapse with workers. ([\#13420](https://github.com/matrix-org/synapse/issues/13420))
+- Prevent unnecessary lookups to any external `get_event` cache. Contributed by Nick @ Beeper (@fizzadar). ([\#13435](https://github.com/matrix-org/synapse/issues/13435))
+- Add some tracing to give more insight into local room joins. ([\#13439](https://github.com/matrix-org/synapse/issues/13439))
+- Rename class `RateLimitConfig` to `RatelimitSettings` and `FederationRateLimitConfig` to `FederationRatelimitSettings`. ([\#13442](https://github.com/matrix-org/synapse/issues/13442))
+- Add some comments about how event push actions are stored. ([\#13445](https://github.com/matrix-org/synapse/issues/13445), [\#13455](https://github.com/matrix-org/synapse/issues/13455))
+- Improve rebuild speed for the "synapse-workers" docker image. ([\#13447](https://github.com/matrix-org/synapse/issues/13447))
+- Fix `@tag_args` being off-by-one with the arguments when tagging a span (tracing). ([\#13452](https://github.com/matrix-org/synapse/issues/13452))
+- Update type of `EventContext.rejected`. ([\#13460](https://github.com/matrix-org/synapse/issues/13460))
+- Use literals in place of `HTTPStatus` constants in tests. ([\#13463](https://github.com/matrix-org/synapse/issues/13463), [\#13469](https://github.com/matrix-org/synapse/issues/13469))
+- Correct a misnamed argument in state res v2 internals. ([\#13467](https://github.com/matrix-org/synapse/issues/13467))
+
+
+Synapse 1.64.0 (2022-08-02)
+===========================
+
+No significant changes since 1.64.0rc2.
+
+
+Deprecation Warning
+-------------------
+
+Synapse v1.66.0 will remove the ability to delegate the tasks of verifying email address ownership, and password reset confirmation, to an identity server.
+
+If you require your homeserver to verify e-mail addresses or to support password resets via e-mail, please configure your homeserver with SMTP access so that it can send e-mails on its own behalf.
+[Consult the configuration documentation for more information.](https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html#email)
+
+
+Synapse 1.64.0rc2 (2022-07-29)
+==============================
+
+This RC reintroduces support for `account_threepid_delegates.email`, which was removed in 1.64.0rc1. It remains deprecated and will be removed altogether in Synapse v1.66.0. ([\#13406](https://github.com/matrix-org/synapse/issues/13406))
+
+
+Synapse 1.64.0rc1 (2022-07-26)
+==============================
+
+This RC removed the ability to delegate the tasks of verifying email address ownership, and password reset confirmation, to an identity server.
+
+We have also stopped building `.deb` packages for Ubuntu 21.10 as it is no longer an active version of Ubuntu.
+
+
+Features
+--------
+
+- Improve error messages when media thumbnails cannot be served. ([\#13038](https://github.com/matrix-org/synapse/issues/13038))
+- Allow pagination from remote event after discovering it from [MSC3030](https://github.com/matrix-org/matrix-spec-proposals/pull/3030) `/timestamp_to_event`. ([\#13205](https://github.com/matrix-org/synapse/issues/13205))
+- Add a `room_type` field in the responses for the list room and room details admin APIs. Contributed by @andrewdoh. ([\#13208](https://github.com/matrix-org/synapse/issues/13208))
+- Add support for room version 10. ([\#13220](https://github.com/matrix-org/synapse/issues/13220))
+- Add per-room rate limiting for room joins. For each room, Synapse now monitors the rate of join events in that room, and throttles additional joins if that rate grows too large. ([\#13253](https://github.com/matrix-org/synapse/issues/13253), [\#13254](https://github.com/matrix-org/synapse/issues/13254), [\#13255](https://github.com/matrix-org/synapse/issues/13255), [\#13276](https://github.com/matrix-org/synapse/issues/13276))
+- Support Implicit TLS (TLS without using a STARTTLS upgrade, typically on port 465) for sending emails, enabled by the new option `force_tls`. Contributed by Jan Schär. ([\#13317](https://github.com/matrix-org/synapse/issues/13317))
+
+
+Bugfixes
+--------
+
+- Fix a bug introduced in Synapse 1.15.0 where adding a user through the Synapse Admin API with a phone number would fail if the `enable_email_notifs` and `email_notifs_for_new_users` options were enabled. Contributed by @thomasweston12. ([\#13263](https://github.com/matrix-org/synapse/issues/13263))
+- Fix a bug introduced in Synapse 1.40.0 where a user invited to a restricted room would be briefly unable to join. ([\#13270](https://github.com/matrix-org/synapse/issues/13270))
+- Fix a long-standing bug where, in rare instances, Synapse could store the incorrect state for a room after a state resolution. ([\#13278](https://github.com/matrix-org/synapse/issues/13278))
+- Fix a bug introduced in v1.18.0 where the `synapse_pushers` metric would overcount pushers when they are replaced. ([\#13296](https://github.com/matrix-org/synapse/issues/13296))
+- Disable autocorrection and autocapitalisation on the username text field shown during registration when using SSO. ([\#13350](https://github.com/matrix-org/synapse/issues/13350))
+- Update locked version of `frozendict` to 2.3.3, which has fixes for memory leaks affecting `/sync`. ([\#13284](https://github.com/matrix-org/synapse/issues/13284), [\#13352](https://github.com/matrix-org/synapse/issues/13352))
+
+
+Improved Documentation
+----------------------
+
+- Provide an example of using the Admin API. Contributed by @jejo86. ([\#13231](https://github.com/matrix-org/synapse/issues/13231))
+- Move the documentation for how URL previews work to the URL preview module. ([\#13233](https://github.com/matrix-org/synapse/issues/13233), [\#13261](https://github.com/matrix-org/synapse/issues/13261))
+- Add another `contrib` script to help set up worker processes. Contributed by @villepeh. ([\#13271](https://github.com/matrix-org/synapse/issues/13271))
+- Document that certain config options were added or changed in Synapse 1.62. Contributed by @behrmann. ([\#13314](https://github.com/matrix-org/synapse/issues/13314))
+- Document the new `rc_invites.per_issuer` throttling option added in Synapse 1.63. ([\#13333](https://github.com/matrix-org/synapse/issues/13333))
+- Mention that BuildKit is needed when building Docker images for tests. ([\#13338](https://github.com/matrix-org/synapse/issues/13338))
+- Improve Caddy reverse proxy documentation. ([\#13344](https://github.com/matrix-org/synapse/issues/13344))
+
+
+Deprecations and Removals
+-------------------------
+
+- Drop tables that were formerly used for groups/communities. ([\#12967](https://github.com/matrix-org/synapse/issues/12967))
+- Drop support for delegating email verification to an external server. ([\#13192](https://github.com/matrix-org/synapse/issues/13192))
+- Drop support for calling `/_matrix/client/v3/account/3pid/bind` without an `id_access_token`, which was not permitted by the spec. Contributed by @Vetchu. ([\#13239](https://github.com/matrix-org/synapse/issues/13239))
+- Stop building `.deb` packages for Ubuntu 21.10 (Impish Indri), which has reached end of life. ([\#13326](https://github.com/matrix-org/synapse/issues/13326))
+
+
+Internal Changes
+----------------
 
-As of this release, Synapse no longer allows the tasks of verifying email address ownership, and password reset confirmation, to be delegated to an identity server. For more information, see the [upgrade notes](https://matrix-org.github.io/synapse/v1.64/upgrade.html#upgrading-to-v1640).
+- Use lower transaction isolation level when purging rooms to avoid serialization errors. Contributed by Nick @ Beeper. ([\#12942](https://github.com/matrix-org/synapse/issues/12942))
+- Remove code which incorrectly attempted to reconcile state with remote servers when processing incoming events. ([\#12943](https://github.com/matrix-org/synapse/issues/12943))
+- Make the AS login method call `Auth.get_user_by_req` for checking the AS token. ([\#13094](https://github.com/matrix-org/synapse/issues/13094))
+- Always use a version of canonicaljson that supports the C implementation of frozendict. ([\#13172](https://github.com/matrix-org/synapse/issues/13172))
+- Add prometheus counters for ephemeral events and to device messages pushed to app services. Contributed by Brad @ Beeper. ([\#13175](https://github.com/matrix-org/synapse/issues/13175))
+- Refactor receipts servlet logic to avoid duplicated code. ([\#13198](https://github.com/matrix-org/synapse/issues/13198))
+- Preparation for database schema simplifications: populate `state_key` and `rejection_reason` for existing rows in the `events` table. ([\#13215](https://github.com/matrix-org/synapse/issues/13215))
+- Remove unused database table `event_reference_hashes`. ([\#13218](https://github.com/matrix-org/synapse/issues/13218))
+- Further reduce queries used sending events when creating new rooms. Contributed by Nick @ Beeper (@fizzadar). ([\#13224](https://github.com/matrix-org/synapse/issues/13224))
+- Call the v2 identity service `/3pid/unbind` endpoint, rather than v1. Contributed by @Vetchu. ([\#13240](https://github.com/matrix-org/synapse/issues/13240))
+- Use an asynchronous cache wrapper for the get event cache. Contributed by Nick @ Beeper (@fizzadar). ([\#13242](https://github.com/matrix-org/synapse/issues/13242), [\#13308](https://github.com/matrix-org/synapse/issues/13308))
+- Optimise federation sender and appservice pusher event stream processing queries. Contributed by Nick @ Beeper (@fizzadar). ([\#13251](https://github.com/matrix-org/synapse/issues/13251))
+- Log the stack when waiting for an entire room to be un-partial stated. ([\#13257](https://github.com/matrix-org/synapse/issues/13257))
+- Fix spurious warning when fetching state after a missing prev event. ([\#13258](https://github.com/matrix-org/synapse/issues/13258))
+- Clean-up tests for notifications. ([\#13260](https://github.com/matrix-org/synapse/issues/13260))
+- Do not fail build if complement with workers fails. ([\#13266](https://github.com/matrix-org/synapse/issues/13266))
+- Don't pull out state in `compute_event_context` for unconflicted state. ([\#13267](https://github.com/matrix-org/synapse/issues/13267), [\#13274](https://github.com/matrix-org/synapse/issues/13274))
+- Reduce the rebuild time for the complement-synapse docker image. ([\#13279](https://github.com/matrix-org/synapse/issues/13279))
+- Don't pull out the full state when creating an event. ([\#13281](https://github.com/matrix-org/synapse/issues/13281), [\#13307](https://github.com/matrix-org/synapse/issues/13307))
+- Upgrade from Poetry 1.1.12 to 1.1.14, to fix bugs when locking packages. ([\#13285](https://github.com/matrix-org/synapse/issues/13285))
+- Make `DictionaryCache` expire full entries if they haven't been queried in a while, even if specific keys have been queried recently. ([\#13292](https://github.com/matrix-org/synapse/issues/13292))
+- Use `HTTPStatus` constants in place of literals in tests. ([\#13297](https://github.com/matrix-org/synapse/issues/13297))
+- Improve performance of query  `_get_subset_users_in_room_with_profiles`. ([\#13299](https://github.com/matrix-org/synapse/issues/13299))
+- Up batch size of `bulk_get_push_rules` and `_get_joined_profiles_from_event_ids`. ([\#13300](https://github.com/matrix-org/synapse/issues/13300))
+- Remove unnecessary `json.dumps` from tests. ([\#13303](https://github.com/matrix-org/synapse/issues/13303))
+- Reduce memory usage of sending dummy events. ([\#13310](https://github.com/matrix-org/synapse/issues/13310))
+- Prevent formatting changes of [#3679](https://github.com/matrix-org/synapse/pull/3679) from appearing in `git blame`. ([\#13311](https://github.com/matrix-org/synapse/issues/13311))
+- Change `get_users_in_room` and `get_rooms_for_user` caches to enable pruning of old entries. ([\#13313](https://github.com/matrix-org/synapse/issues/13313))
+- Validate federation destinations and log an error if a destination is invalid. ([\#13318](https://github.com/matrix-org/synapse/issues/13318))
+- Fix `FederationClient.get_pdu()` returning events from the cache as `outliers` instead of original events we saw over federation. ([\#13320](https://github.com/matrix-org/synapse/issues/13320))
+- Reduce memory usage of state caches. ([\#13323](https://github.com/matrix-org/synapse/issues/13323))
+- Reduce the amount of state we store in the `state_cache`. ([\#13324](https://github.com/matrix-org/synapse/issues/13324))
+- Add missing type hints to open tracing module. ([\#13328](https://github.com/matrix-org/synapse/issues/13328), [\#13345](https://github.com/matrix-org/synapse/issues/13345), [\#13362](https://github.com/matrix-org/synapse/issues/13362))
+- Remove old base slaved store and de-duplicate cache ID generators. Contributed by Nick @ Beeper (@fizzadar). ([\#13329](https://github.com/matrix-org/synapse/issues/13329), [\#13349](https://github.com/matrix-org/synapse/issues/13349))
+- When reporting metrics is enabled, use ~8x less data to describe DB transaction metrics. ([\#13342](https://github.com/matrix-org/synapse/issues/13342))
+- Faster room joins: skip soft fail checks while Synapse only has partial room state, since the current membership of event senders may not be accurately known. ([\#13354](https://github.com/matrix-org/synapse/issues/13354))
 
 
 Synapse 1.63.1 (2022-07-20)
diff --git a/README.rst b/README.rst
index 219e32de8e..84e5310309 100644
--- a/README.rst
+++ b/README.rst
@@ -2,107 +2,111 @@
 Synapse |support| |development| |documentation| |license| |pypi| |python|
 =========================================================================
 
+Synapse is an open-source `Matrix <https://matrix.org/>`_ homeserver written and
+maintained by the Matrix.org Foundation. We began rapid development began in 2014,
+reaching v1.0.0 in 2019. Development on Synapse and the Matrix protocol itself continues
+in earnest today.
+
+Briefly, Matrix is an open standard for communications on the internet, supporting
+federation, encryption and VoIP. Matrix.org has more to say about the `goals of the
+Matrix project <https://matrix.org/docs/guides/introduction>`_, and the `formal specification
+<https://spec.matrix.org/>`_ describes the technical details.
+
 .. contents::
 
-Introduction
-============
+Installing and configuration
+============================
 
-Matrix is an ambitious new ecosystem for open federated Instant Messaging and
-VoIP.  The basics you need to know to get up and running are:
+The Synapse documentation describes `how to install Synapse <https://matrix-org.github.io/synapse/latest/setup/installation.html>`_. We recommend using
+`Docker images <https://matrix-org.github.io/synapse/latest/setup/installation.html#docker-images-and-ansible-playbooks>`_ or `Debian packages from Matrix.org
+<https://matrix-org.github.io/synapse/latest/setup/installation.html#matrixorg-packages>`_.
 
-- Everything in Matrix happens in a room.  Rooms are distributed and do not
-  exist on any single server.  Rooms can be located using convenience aliases
-  like ``#matrix:matrix.org`` or ``#test:localhost:8448``.
+.. _federation:
 
-- Matrix user IDs look like ``@matthew:matrix.org`` (although in the future
-  you will normally refer to yourself and others using a third party identifier
-  (3PID): email address, phone number, etc rather than manipulating Matrix user IDs)
+Synapse has a variety of `config options
+<https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html>`_
+which can be used to customise its behaviour after installation.
+There are additional details on how to `configure Synapse for federation here
+<https://matrix-org.github.io/synapse/latest/federate.html>`_.
 
-The overall architecture is::
+.. _reverse-proxy:
 
-      client <----> homeserver <=====================> homeserver <----> client
-             https://somewhere.org/_matrix      https://elsewhere.net/_matrix
+Using a reverse proxy with Synapse
+----------------------------------
 
-``#matrix:matrix.org`` is the official support room for Matrix, and can be
-accessed by any client from https://matrix.org/docs/projects/try-matrix-now.html or
-via IRC bridge at irc://irc.libera.chat/matrix.
+It is recommended to put a reverse proxy such as
+`nginx <https://nginx.org/en/docs/http/ngx_http_proxy_module.html>`_,
+`Apache <https://httpd.apache.org/docs/current/mod/mod_proxy_http.html>`_,
+`Caddy <https://caddyserver.com/docs/quick-starts/reverse-proxy>`_,
+`HAProxy <https://www.haproxy.org/>`_ or
+`relayd <https://man.openbsd.org/relayd.8>`_ in front of Synapse. One advantage of
+doing so is that it means that you can expose the default https port (443) to
+Matrix clients without needing to run Synapse with root privileges.
+For information on configuring one, see `the reverse proxy docs
+<https://matrix-org.github.io/synapse/latest/reverse_proxy.html>`_.
 
-Synapse is currently in rapid development, but as of version 0.5 we believe it
-is sufficiently stable to be run as an internet-facing service for real usage!
+Upgrading an existing Synapse
+-----------------------------
 
-About Matrix
-============
+The instructions for upgrading Synapse are in `the upgrade notes`_.
+Please check these instructions as upgrading may require extra steps for some
+versions of Synapse.
 
-Matrix specifies a set of pragmatic RESTful HTTP JSON APIs as an open standard,
-which handle:
+.. _the upgrade notes: https://matrix-org.github.io/synapse/develop/upgrade.html
 
-- Creating and managing fully distributed chat rooms with no
-  single points of control or failure
-- Eventually-consistent cryptographically secure synchronisation of room
-  state across a global open network of federated servers and services
-- Sending and receiving extensible messages in a room with (optional)
-  end-to-end encryption
-- Inviting, joining, leaving, kicking, banning room members
-- Managing user accounts (registration, login, logout)
-- Using 3rd Party IDs (3PIDs) such as email addresses, phone numbers,
-  Facebook accounts to authenticate, identify and discover users on Matrix.
-- Placing 1:1 VoIP and Video calls
 
-These APIs are intended to be implemented on a wide range of servers, services
-and clients, letting developers build messaging and VoIP functionality on top
-of the entirely open Matrix ecosystem rather than using closed or proprietary
-solutions. The hope is for Matrix to act as the building blocks for a new
-generation of fully open and interoperable messaging and VoIP apps for the
-internet.
+Platform dependencies
+---------------------
 
-Synapse is a Matrix "homeserver" implementation developed by the matrix.org core
-team, written in Python 3/Twisted.
+Synapse uses a number of platform dependencies such as Python and PostgreSQL,
+and aims to follow supported upstream versions. See the
+`deprecation policy <https://matrix-org.github.io/synapse/latest/deprecation_policy.html>`_
+for more details.
 
-In Matrix, every user runs one or more Matrix clients, which connect through to
-a Matrix homeserver. The homeserver stores all their personal chat history and
-user account information - much as a mail client connects through to an
-IMAP/SMTP server. Just like email, you can either run your own Matrix
-homeserver and control and own your own communications and history or use one
-hosted by someone else (e.g. matrix.org) - there is no single point of control
-or mandatory service provider in Matrix, unlike WhatsApp, Facebook, Hangouts,
-etc.
 
-We'd like to invite you to join #matrix:matrix.org (via
-https://matrix.org/docs/projects/try-matrix-now.html), run a homeserver, take a look
-at the `Matrix spec <https://matrix.org/docs/spec>`_, and experiment with the
-`APIs <https://matrix.org/docs/api>`_ and `Client SDKs
-<https://matrix.org/docs/projects/try-matrix-now.html#client-sdks>`_.
+Security note
+-------------
 
-Thanks for using Matrix!
+Matrix serves raw, user-supplied data in some APIs -- specifically the `content
+repository endpoints`_.
 
-Support
-=======
+.. _content repository endpoints: https://matrix.org/docs/spec/client_server/latest.html#get-matrix-media-r0-download-servername-mediaid
 
-For support installing or managing Synapse, please join |room|_ (from a matrix.org
-account if necessary) and ask questions there. We do not use GitHub issues for
-support requests, only for bug reports and feature requests.
+Whilst we make a reasonable effort to mitigate against XSS attacks (for
+instance, by using `CSP`_), a Matrix homeserver should not be hosted on a
+domain hosting other web applications. This especially applies to sharing
+the domain with Matrix web clients and other sensitive applications like
+webmail. See
+https://developer.github.com/changes/2014-04-25-user-content-security for more
+information.
 
-Synapse's documentation is `nicely rendered on GitHub Pages <https://matrix-org.github.io/synapse>`_,
-with its source available in |docs|_.
+.. _CSP: https://github.com/matrix-org/synapse/pull/1021
 
-.. |room| replace:: ``#synapse:matrix.org``
-.. _room: https://matrix.to/#/#synapse:matrix.org
+Ideally, the homeserver should not simply be on a different subdomain, but on
+a completely different `registered domain`_ (also known as top-level site or
+eTLD+1). This is because `some attacks`_ are still possible as long as the two
+applications share the same registered domain.
 
-.. |docs| replace:: ``docs``
-.. _docs: docs
+.. _registered domain: https://tools.ietf.org/html/draft-ietf-httpbis-rfc6265bis-03#section-2.3
 
-Synapse Installation
-====================
+.. _some attacks: https://en.wikipedia.org/wiki/Session_fixation#Attacks_using_cross-subdomain_cookie
 
-.. _federation:
+To illustrate this with an example, if your Element Web or other sensitive web
+application is hosted on ``A.example1.com``, you should ideally host Synapse on
+``example2.com``. Some amount of protection is offered by hosting on
+``B.example1.com`` instead, so this is also acceptable in some scenarios.
+However, you should *not* host your Synapse on ``A.example1.com``.
+
+Note that all of the above refers exclusively to the domain used in Synapse's
+``public_baseurl`` setting. In particular, it has no bearing on the domain
+mentioned in MXIDs hosted on that server.
 
-* For details on how to install synapse, see
-  `Installation Instructions <https://matrix-org.github.io/synapse/latest/setup/installation.html>`_.
-* For specific details on how to configure Synapse for federation see `docs/federate.md <docs/federate.md>`_
+Following this advice ensures that even if an XSS is found in Synapse, the
+impact to other applications will be minimal.
 
 
-Connecting to Synapse from a client
-===================================
+Testing a new installation
+==========================
 
 The easiest way to try out your new Synapse installation is by connecting to it
 from a web client.
@@ -129,11 +133,20 @@ Registering a new user from a client
 ------------------------------------
 
 By default, registration of new users via Matrix clients is disabled. To enable
-it, specify ``enable_registration: true`` in ``homeserver.yaml``. (It is then
-recommended to also set up CAPTCHA - see `<docs/CAPTCHA_SETUP.md>`_.)
+it:
+
+1. In the
+   `registration config section <https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html#registration>`_
+   set ``enable_registration: true`` in ``homeserver.yaml``.
+2. Then **either**:
 
-Once ``enable_registration`` is set to ``true``, it is possible to register a
-user via a Matrix client.
+   a. set up a `CAPTCHA <https://matrix-org.github.io/synapse/latest/CAPTCHA_SETUP.html>`_, or
+   b. set ``enable_registration_without_verification: true`` in ``homeserver.yaml``.
+
+We **strongly** recommend using a CAPTCHA, particularly if your homeserver is exposed to
+the public internet. Without it, anyone can freely register accounts on your homeserver.
+This can be exploited by attackers to create spambots targetting the rest of the Matrix
+federation.
 
 Your new user name will be formed partly from the ``server_name``, and partly
 from a localpart you specify when you create the account. Your name will take
@@ -146,71 +159,22 @@ the form of::
 As when logging in, you will need to specify a "Custom server".  Specify your
 desired ``localpart`` in the 'User name' box.
 
-Security note
-=============
+Troubleshooting and support
+===========================
 
-Matrix serves raw, user-supplied data in some APIs -- specifically the `content
-repository endpoints`_.
+The `Admin FAQ <https://matrix-org.github.io/synapse/latest/usage/administration/admin_faq.html>`_
+includes tips on dealing with some common problems. For more details, see
+`Synapse's wider documentation <https://matrix-org.github.io/synapse/latest/>`_.
 
-.. _content repository endpoints: https://matrix.org/docs/spec/client_server/latest.html#get-matrix-media-r0-download-servername-mediaid
-
-Whilst we make a reasonable effort to mitigate against XSS attacks (for
-instance, by using `CSP`_), a Matrix homeserver should not be hosted on a
-domain hosting other web applications. This especially applies to sharing
-the domain with Matrix web clients and other sensitive applications like
-webmail. See
-https://developer.github.com/changes/2014-04-25-user-content-security for more
-information.
-
-.. _CSP: https://github.com/matrix-org/synapse/pull/1021
-
-Ideally, the homeserver should not simply be on a different subdomain, but on
-a completely different `registered domain`_ (also known as top-level site or
-eTLD+1). This is because `some attacks`_ are still possible as long as the two
-applications share the same registered domain.
-
-.. _registered domain: https://tools.ietf.org/html/draft-ietf-httpbis-rfc6265bis-03#section-2.3
-
-.. _some attacks: https://en.wikipedia.org/wiki/Session_fixation#Attacks_using_cross-subdomain_cookie
+For additional support installing or managing Synapse, please ask in the community
+support room |room|_ (from a matrix.org account if necessary). We do not use GitHub
+issues for support requests, only for bug reports and feature requests.
 
-To illustrate this with an example, if your Element Web or other sensitive web
-application is hosted on ``A.example1.com``, you should ideally host Synapse on
-``example2.com``. Some amount of protection is offered by hosting on
-``B.example1.com`` instead, so this is also acceptable in some scenarios.
-However, you should *not* host your Synapse on ``A.example1.com``.
-
-Note that all of the above refers exclusively to the domain used in Synapse's
-``public_baseurl`` setting. In particular, it has no bearing on the domain
-mentioned in MXIDs hosted on that server.
-
-Following this advice ensures that even if an XSS is found in Synapse, the
-impact to other applications will be minimal.
-
-
-Upgrading an existing Synapse
-=============================
-
-The instructions for upgrading synapse are in `the upgrade notes`_.
-Please check these instructions as upgrading may require extra steps for some
-versions of synapse.
-
-.. _the upgrade notes: https://matrix-org.github.io/synapse/develop/upgrade.html
-
-.. _reverse-proxy:
-
-Using a reverse proxy with Synapse
-==================================
-
-It is recommended to put a reverse proxy such as
-`nginx <https://nginx.org/en/docs/http/ngx_http_proxy_module.html>`_,
-`Apache <https://httpd.apache.org/docs/current/mod/mod_proxy_http.html>`_,
-`Caddy <https://caddyserver.com/docs/quick-starts/reverse-proxy>`_,
-`HAProxy <https://www.haproxy.org/>`_ or
-`relayd <https://man.openbsd.org/relayd.8>`_ in front of Synapse. One advantage of
-doing so is that it means that you can expose the default https port (443) to
-Matrix clients without needing to run Synapse with root privileges.
+.. |room| replace:: ``#synapse:matrix.org``
+.. _room: https://matrix.to/#/#synapse:matrix.org
 
-For information on configuring one, see `<docs/reverse_proxy.md>`_.
+.. |docs| replace:: ``docs``
+.. _docs: docs
 
 Identity Servers
 ================
@@ -242,34 +206,15 @@ an email address with your account, or send an invite to another user via their
 email address.
 
 
-Password reset
-==============
-
-Users can reset their password through their client. Alternatively, a server admin
-can reset a users password using the `admin API <docs/admin_api/user_admin_api.md#reset-password>`_
-or by directly editing the database as shown below.
-
-First calculate the hash of the new password::
-
-    $ ~/synapse/env/bin/hash_password
-    Password:
-    Confirm password:
-    $2a$12$xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
-
-Then update the ``users`` table in the database::
-
-    UPDATE users SET password_hash='$2a$12$xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'
-        WHERE name='@test:test.com';
-
-
-Synapse Development
-===================
+Development
+===========
 
+We welcome contributions to Synapse from the community!
 The best place to get started is our
 `guide for contributors <https://matrix-org.github.io/synapse/latest/development/contributing_guide.html>`_.
 This is part of our larger `documentation <https://matrix-org.github.io/synapse/latest>`_, which includes
-information for synapse developers as well as synapse administrators.
 
+information for Synapse developers as well as Synapse administrators.
 Developers might be particularly interested in:
 
 * `Synapse's database schema <https://matrix-org.github.io/synapse/latest/development/database_schema.html>`_,
@@ -280,187 +225,6 @@ Alongside all that, join our developer community on Matrix:
 `#synapse-dev:matrix.org <https://matrix.to/#/#synapse-dev:matrix.org>`_, featuring real humans!
 
 
-Quick start
------------
-
-Before setting up a development environment for synapse, make sure you have the
-system dependencies (such as the python header files) installed - see
-`Platform-specific prerequisites <https://matrix-org.github.io/synapse/latest/setup/installation.html#platform-specific-prerequisites>`_.
-
-To check out a synapse for development, clone the git repo into a working
-directory of your choice::
-
-    git clone https://github.com/matrix-org/synapse.git
-    cd synapse
-
-Synapse has a number of external dependencies. We maintain a fixed development
-environment using `Poetry <https://python-poetry.org/>`_. First, install poetry. We recommend::
-
-    pip install --user pipx
-    pipx install poetry
-
-as described `here <https://python-poetry.org/docs/#installing-with-pipx>`_.
-(See `poetry's installation docs <https://python-poetry.org/docs/#installation>`_
-for other installation methods.) Then ask poetry to create a virtual environment
-from the project and install Synapse's dependencies::
-
-    poetry install --extras "all test"
-
-This will run a process of downloading and installing all the needed
-dependencies into a virtual env.
-
-We recommend using the demo which starts 3 federated instances running on ports `8080` - `8082`::
-
-    poetry run ./demo/start.sh
-
-(to stop, you can use ``poetry run ./demo/stop.sh``)
-
-See the `demo documentation <https://matrix-org.github.io/synapse/develop/development/demo.html>`_
-for more information.
-
-If you just want to start a single instance of the app and run it directly::
-
-    # Create the homeserver.yaml config once
-    poetry run synapse_homeserver \
-      --server-name my.domain.name \
-      --config-path homeserver.yaml \
-      --generate-config \
-      --report-stats=[yes|no]
-
-    # Start the app
-    poetry run synapse_homeserver --config-path homeserver.yaml
-
-
-Running the unit tests
-----------------------
-
-After getting up and running, you may wish to run Synapse's unit tests to
-check that everything is installed correctly::
-
-    poetry run trial tests
-
-This should end with a 'PASSED' result (note that exact numbers will
-differ)::
-
-    Ran 1337 tests in 716.064s
-
-    PASSED (skips=15, successes=1322)
-
-For more tips on running the unit tests, like running a specific test or
-to see the logging output, see the `CONTRIBUTING doc <CONTRIBUTING.md#run-the-unit-tests>`_.
-
-
-Running the Integration Tests
------------------------------
-
-Synapse is accompanied by `SyTest <https://github.com/matrix-org/sytest>`_,
-a Matrix homeserver integration testing suite, which uses HTTP requests to
-access the API as a Matrix client would. It is able to run Synapse directly from
-the source tree, so installation of the server is not required.
-
-Testing with SyTest is recommended for verifying that changes related to the
-Client-Server API are functioning correctly. See the `SyTest installation
-instructions <https://github.com/matrix-org/sytest#installing>`_ for details.
-
-
-Platform dependencies
-=====================
-
-Synapse uses a number of platform dependencies such as Python and PostgreSQL,
-and aims to follow supported upstream versions. See the
-`<docs/deprecation_policy.md>`_ document for more details.
-
-
-Troubleshooting
-===============
-
-Need help? Join our community support room on Matrix:
-`#synapse:matrix.org <https://matrix.to/#/#synapse:matrix.org>`_
-
-Running out of File Handles
----------------------------
-
-If synapse runs out of file handles, it typically fails badly - live-locking
-at 100% CPU, and/or failing to accept new TCP connections (blocking the
-connecting client).  Matrix currently can legitimately use a lot of file handles,
-thanks to busy rooms like #matrix:matrix.org containing hundreds of participating
-servers.  The first time a server talks in a room it will try to connect
-simultaneously to all participating servers, which could exhaust the available
-file descriptors between DNS queries & HTTPS sockets, especially if DNS is slow
-to respond. (We need to improve the routing algorithm used to be better than
-full mesh, but as of March 2019 this hasn't happened yet).
-
-If you hit this failure mode, we recommend increasing the maximum number of
-open file handles to be at least 4096 (assuming a default of 1024 or 256).
-This is typically done by editing ``/etc/security/limits.conf``
-
-Separately, Synapse may leak file handles if inbound HTTP requests get stuck
-during processing - e.g. blocked behind a lock or talking to a remote server etc.
-This is best diagnosed by matching up the 'Received request' and 'Processed request'
-log lines and looking for any 'Processed request' lines which take more than
-a few seconds to execute. Please let us know at #synapse:matrix.org if
-you see this failure mode so we can help debug it, however.
-
-Help!! Synapse is slow and eats all my RAM/CPU!
------------------------------------------------
-
-First, ensure you are running the latest version of Synapse, using Python 3
-with a PostgreSQL database.
-
-Synapse's architecture is quite RAM hungry currently - we deliberately
-cache a lot of recent room data and metadata in RAM in order to speed up
-common requests. We'll improve this in the future, but for now the easiest
-way to either reduce the RAM usage (at the risk of slowing things down)
-is to set the almost-undocumented ``SYNAPSE_CACHE_FACTOR`` environment
-variable. The default is 0.5, which can be decreased to reduce RAM usage
-in memory constrained enviroments, or increased if performance starts to
-degrade.
-
-However, degraded performance due to a low cache factor, common on
-machines with slow disks, often leads to explosions in memory use due
-backlogged requests. In this case, reducing the cache factor will make
-things worse. Instead, try increasing it drastically. 2.0 is a good
-starting value.
-
-Using `libjemalloc <http://jemalloc.net/>`_ can also yield a significant
-improvement in overall memory use, and especially in terms of giving back
-RAM to the OS. To use it, the library must simply be put in the
-LD_PRELOAD environment variable when launching Synapse. On Debian, this
-can be done by installing the ``libjemalloc1`` package and adding this
-line to ``/etc/default/matrix-synapse``::
-
-    LD_PRELOAD=/usr/lib/x86_64-linux-gnu/libjemalloc.so.1
-
-This can make a significant difference on Python 2.7 - it's unclear how
-much of an improvement it provides on Python 3.x.
-
-If you're encountering high CPU use by the Synapse process itself, you
-may be affected by a bug with presence tracking that leads to a
-massive excess of outgoing federation requests (see `discussion
-<https://github.com/matrix-org/synapse/issues/3971>`_). If metrics
-indicate that your server is also issuing far more outgoing federation
-requests than can be accounted for by your users' activity, this is a
-likely cause. The misbehavior can be worked around by setting
-the following in the Synapse config file:
-
-.. code-block:: yaml
-
-   presence:
-       enabled: false
-
-People can't accept room invitations from me
---------------------------------------------
-
-The typical failure mode here is that you send an invitation to someone
-to join a room or direct chat, but when they go to accept it, they get an
-error (typically along the lines of "Invalid signature"). They might see
-something like the following in their logs::
-
-    2019-09-11 19:32:04,271 - synapse.federation.transport.server - 288 - WARNING - GET-11752 - authenticate_request failed: 401: Invalid signature for server <server> with key ed25519:a_EqML: Unable to verify signature for <server>
-
-This is normally caused by a misconfiguration in your reverse-proxy. See
-`<docs/reverse_proxy.md>`_ and double-check that your settings are correct.
-
 .. |support| image:: https://img.shields.io/matrix/synapse:matrix.org?label=support&logo=matrix
   :alt: (get support on #synapse:matrix.org)
   :target: https://matrix.to/#/#synapse:matrix.org
diff --git a/changelog.d/12942.misc b/changelog.d/12942.misc
deleted file mode 100644
index acb2558d57..0000000000
--- a/changelog.d/12942.misc
+++ /dev/null
@@ -1 +0,0 @@
-Use lower isolation level when purging rooms to avoid serialization errors. Contributed by Nick @ Beeper.
diff --git a/changelog.d/12943.misc b/changelog.d/12943.misc
deleted file mode 100644
index f66bb3ec32..0000000000
--- a/changelog.d/12943.misc
+++ /dev/null
@@ -1 +0,0 @@
-Remove code which incorrectly attempted to reconcile state with remote servers when processing incoming events.
diff --git a/changelog.d/12967.removal b/changelog.d/12967.removal
deleted file mode 100644
index 0aafd6a4d9..0000000000
--- a/changelog.d/12967.removal
+++ /dev/null
@@ -1 +0,0 @@
-Drop tables used for groups/communities.
diff --git a/changelog.d/13038.feature b/changelog.d/13038.feature
deleted file mode 100644
index 1278f1b4e9..0000000000
--- a/changelog.d/13038.feature
+++ /dev/null
@@ -1 +0,0 @@
-Provide more info why we don't have any thumbnails to serve.
diff --git a/changelog.d/13094.misc b/changelog.d/13094.misc
deleted file mode 100644
index f1e55ae476..0000000000
--- a/changelog.d/13094.misc
+++ /dev/null
@@ -1 +0,0 @@
-Make the AS login method call `Auth.get_user_by_req` for checking the AS token.
diff --git a/changelog.d/13172.misc b/changelog.d/13172.misc
deleted file mode 100644
index 124a1b3662..0000000000
--- a/changelog.d/13172.misc
+++ /dev/null
@@ -1 +0,0 @@
-Always use a version of canonicaljson that supports the C implementation of frozendict.
diff --git a/changelog.d/13175.misc b/changelog.d/13175.misc
deleted file mode 100644
index f273b3d6ca..0000000000
--- a/changelog.d/13175.misc
+++ /dev/null
@@ -1 +0,0 @@
-Add prometheus counters for ephemeral events and to device messages pushed to app services. Contributed by Brad @ Beeper.
diff --git a/changelog.d/13192.removal b/changelog.d/13192.removal
deleted file mode 100644
index a7dffd1c48..0000000000
--- a/changelog.d/13192.removal
+++ /dev/null
@@ -1 +0,0 @@
-Drop support for delegating email verification to an external server.
diff --git a/changelog.d/13198.misc b/changelog.d/13198.misc
deleted file mode 100644
index 5aef2432df..0000000000
--- a/changelog.d/13198.misc
+++ /dev/null
@@ -1 +0,0 @@
-Refactor receipts servlet logic to avoid duplicated code.
diff --git a/changelog.d/13208.feature b/changelog.d/13208.feature
deleted file mode 100644
index b0c5f090ee..0000000000
--- a/changelog.d/13208.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add a `room_type` field in the responses for the list room and room details admin API. Contributed by @andrewdoh.
\ No newline at end of file
diff --git a/changelog.d/13215.misc b/changelog.d/13215.misc
deleted file mode 100644
index 3da35addb3..0000000000
--- a/changelog.d/13215.misc
+++ /dev/null
@@ -1 +0,0 @@
-Preparation for database schema simplifications: populate `state_key` and `rejection_reason` for existing rows in the `events` table.
diff --git a/changelog.d/13218.misc b/changelog.d/13218.misc
deleted file mode 100644
index b1c8e5c747..0000000000
--- a/changelog.d/13218.misc
+++ /dev/null
@@ -1 +0,0 @@
-Remove unused database table `event_reference_hashes`.
diff --git a/changelog.d/13220.feature b/changelog.d/13220.feature
deleted file mode 100644
index 9b0240fdc8..0000000000
--- a/changelog.d/13220.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add support for room version 10.
diff --git a/changelog.d/13224.misc b/changelog.d/13224.misc
deleted file mode 100644
index 41f8693b74..0000000000
--- a/changelog.d/13224.misc
+++ /dev/null
@@ -1 +0,0 @@
-Further reduce queries used sending events when creating new rooms. Contributed by Nick @ Beeper (@fizzadar).
diff --git a/changelog.d/13231.doc b/changelog.d/13231.doc
deleted file mode 100644
index e750f9da49..0000000000
--- a/changelog.d/13231.doc
+++ /dev/null
@@ -1 +0,0 @@
-Provide an example of using the Admin API. Contributed by @jejo86.
diff --git a/changelog.d/13233.doc b/changelog.d/13233.doc
deleted file mode 100644
index 3eaea7c5e3..0000000000
--- a/changelog.d/13233.doc
+++ /dev/null
@@ -1 +0,0 @@
-Move the documentation for how URL previews work to the URL preview module.
diff --git a/changelog.d/13239.removal b/changelog.d/13239.removal
deleted file mode 100644
index 8f6045176d..0000000000
--- a/changelog.d/13239.removal
+++ /dev/null
@@ -1 +0,0 @@
-Drop support for calling `/_matrix/client/v3/account/3pid/bind` without an `id_access_token`, which was not permitted by the spec. Contributed by @Vetchu.
\ No newline at end of file
diff --git a/changelog.d/13240.misc b/changelog.d/13240.misc
deleted file mode 100644
index 0567e47d64..0000000000
--- a/changelog.d/13240.misc
+++ /dev/null
@@ -1 +0,0 @@
-Call the v2 identity service `/3pid/unbind` endpoint, rather than v1.
\ No newline at end of file
diff --git a/changelog.d/13242.misc b/changelog.d/13242.misc
deleted file mode 100644
index 7f8ec0815f..0000000000
--- a/changelog.d/13242.misc
+++ /dev/null
@@ -1 +0,0 @@
-Use an asynchronous cache wrapper for the get event cache. Contributed by Nick @ Beeper (@fizzadar).
diff --git a/changelog.d/13251.misc b/changelog.d/13251.misc
deleted file mode 100644
index 526369e403..0000000000
--- a/changelog.d/13251.misc
+++ /dev/null
@@ -1 +0,0 @@
-Optimise federation sender and appservice pusher event stream processing queries. Contributed by Nick @ Beeper (@fizzadar).
diff --git a/changelog.d/13253.misc b/changelog.d/13253.misc
deleted file mode 100644
index cba6b9ee0f..0000000000
--- a/changelog.d/13253.misc
+++ /dev/null
@@ -1 +0,0 @@
-Preparatory work for a per-room rate limiter on joins.
diff --git a/changelog.d/13254.misc b/changelog.d/13254.misc
deleted file mode 100644
index cba6b9ee0f..0000000000
--- a/changelog.d/13254.misc
+++ /dev/null
@@ -1 +0,0 @@
-Preparatory work for a per-room rate limiter on joins.
diff --git a/changelog.d/13255.misc b/changelog.d/13255.misc
deleted file mode 100644
index cba6b9ee0f..0000000000
--- a/changelog.d/13255.misc
+++ /dev/null
@@ -1 +0,0 @@
-Preparatory work for a per-room rate limiter on joins.
diff --git a/changelog.d/13257.misc b/changelog.d/13257.misc
deleted file mode 100644
index 5fc1388520..0000000000
--- a/changelog.d/13257.misc
+++ /dev/null
@@ -1 +0,0 @@
-Log the stack when waiting for an entire room to be un-partial stated.
diff --git a/changelog.d/13258.misc b/changelog.d/13258.misc
deleted file mode 100644
index a187c46aa6..0000000000
--- a/changelog.d/13258.misc
+++ /dev/null
@@ -1 +0,0 @@
-Fix spurious warning when fetching state after a missing prev event.
diff --git a/changelog.d/13260.misc b/changelog.d/13260.misc
deleted file mode 100644
index b55ff32c76..0000000000
--- a/changelog.d/13260.misc
+++ /dev/null
@@ -1 +0,0 @@
-Clean-up tests for notifications.
diff --git a/changelog.d/13261.doc b/changelog.d/13261.doc
deleted file mode 100644
index 3eaea7c5e3..0000000000
--- a/changelog.d/13261.doc
+++ /dev/null
@@ -1 +0,0 @@
-Move the documentation for how URL previews work to the URL preview module.
diff --git a/changelog.d/13263.bugfix b/changelog.d/13263.bugfix
deleted file mode 100644
index 91e1d1e7eb..0000000000
--- a/changelog.d/13263.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix a bug introduced in Synapse 1.15.0 where adding a user through the Synapse Admin API with a phone number would fail if the "enable_email_notifs" and "email_notifs_for_new_users" options were enabled. Contributed by @thomasweston12.
diff --git a/changelog.d/13266.misc b/changelog.d/13266.misc
deleted file mode 100644
index d583acb81b..0000000000
--- a/changelog.d/13266.misc
+++ /dev/null
@@ -1 +0,0 @@
-Do not fail build if complement with workers fails.
diff --git a/changelog.d/13267.misc b/changelog.d/13267.misc
deleted file mode 100644
index a334414320..0000000000
--- a/changelog.d/13267.misc
+++ /dev/null
@@ -1 +0,0 @@
-Don't pull out state in `compute_event_context` for unconflicted state.
diff --git a/changelog.d/13270.bugfix b/changelog.d/13270.bugfix
deleted file mode 100644
index d023b25eea..0000000000
--- a/changelog.d/13270.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix a bug introduced in Synapse 1.40 where a user invited to a restricted room would be briefly unable to join.
diff --git a/changelog.d/13271.doc b/changelog.d/13271.doc
deleted file mode 100644
index b50e60d029..0000000000
--- a/changelog.d/13271.doc
+++ /dev/null
@@ -1 +0,0 @@
-Add another `contrib` script to help set up worker processes. Contributed by @villepeh.
diff --git a/changelog.d/13274.misc b/changelog.d/13274.misc
deleted file mode 100644
index a334414320..0000000000
--- a/changelog.d/13274.misc
+++ /dev/null
@@ -1 +0,0 @@
-Don't pull out state in `compute_event_context` for unconflicted state.
diff --git a/changelog.d/13276.feature b/changelog.d/13276.feature
deleted file mode 100644
index 068d158ed5..0000000000
--- a/changelog.d/13276.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add per-room rate limiting for room joins. For each room, Synapse now monitors the rate of join events in that room, and throttle additional joins if that rate grows too large.
diff --git a/changelog.d/13278.bugfix b/changelog.d/13278.bugfix
deleted file mode 100644
index 49e9377c79..0000000000
--- a/changelog.d/13278.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix long-standing bug where in rare instances Synapse could store the incorrect state for a room after a state resolution.
diff --git a/changelog.d/13279.misc b/changelog.d/13279.misc
deleted file mode 100644
index a083d2af2a..0000000000
--- a/changelog.d/13279.misc
+++ /dev/null
@@ -1 +0,0 @@
-Reduce the rebuild time for the complement-synapse docker image.
diff --git a/changelog.d/13281.misc b/changelog.d/13281.misc
deleted file mode 100644
index dea51d1362..0000000000
--- a/changelog.d/13281.misc
+++ /dev/null
@@ -1 +0,0 @@
-Don't pull out the full state when creating an event.
diff --git a/changelog.d/13284.misc b/changelog.d/13284.misc
deleted file mode 100644
index fa9743a10e..0000000000
--- a/changelog.d/13284.misc
+++ /dev/null
@@ -1 +0,0 @@
-Update locked version of `frozendict` to 2.3.2, which has a fix for a memory leak.
diff --git a/changelog.d/13285.misc b/changelog.d/13285.misc
deleted file mode 100644
index b7bcbadb5b..0000000000
--- a/changelog.d/13285.misc
+++ /dev/null
@@ -1 +0,0 @@
-Upgrade from Poetry 1.1.14 to 1.1.12, to fix bugs when locking packages.
diff --git a/changelog.d/13296.bugfix b/changelog.d/13296.bugfix
deleted file mode 100644
index ff0eb2b4a1..0000000000
--- a/changelog.d/13296.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix a bug introduced in v1.18.0 where the `synapse_pushers` metric would overcount pushers when they are replaced.
diff --git a/changelog.d/13297.misc b/changelog.d/13297.misc
deleted file mode 100644
index 545a62369f..0000000000
--- a/changelog.d/13297.misc
+++ /dev/null
@@ -1 +0,0 @@
-Use `HTTPStatus` constants in place of literals in tests.
\ No newline at end of file
diff --git a/changelog.d/13299.misc b/changelog.d/13299.misc
deleted file mode 100644
index a9d5566873..0000000000
--- a/changelog.d/13299.misc
+++ /dev/null
@@ -1 +0,0 @@
-Improve performance of query  `_get_subset_users_in_room_with_profiles`.
diff --git a/changelog.d/13300.misc b/changelog.d/13300.misc
deleted file mode 100644
index ee58add3c4..0000000000
--- a/changelog.d/13300.misc
+++ /dev/null
@@ -1 +0,0 @@
-Up batch size of `bulk_get_push_rules` and `_get_joined_profiles_from_event_ids`.
diff --git a/changelog.d/13303.misc b/changelog.d/13303.misc
deleted file mode 100644
index 03f64ab171..0000000000
--- a/changelog.d/13303.misc
+++ /dev/null
@@ -1 +0,0 @@
-Remove unnecessary `json.dumps` from tests.
\ No newline at end of file
diff --git a/changelog.d/13307.misc b/changelog.d/13307.misc
deleted file mode 100644
index 45b628ce13..0000000000
--- a/changelog.d/13307.misc
+++ /dev/null
@@ -1 +0,0 @@
-Don't pull out the full state when creating an event.
\ No newline at end of file
diff --git a/changelog.d/13308.misc b/changelog.d/13308.misc
deleted file mode 100644
index 7f8ec0815f..0000000000
--- a/changelog.d/13308.misc
+++ /dev/null
@@ -1 +0,0 @@
-Use an asynchronous cache wrapper for the get event cache. Contributed by Nick @ Beeper (@fizzadar).
diff --git a/changelog.d/13310.misc b/changelog.d/13310.misc
deleted file mode 100644
index eaf570e058..0000000000
--- a/changelog.d/13310.misc
+++ /dev/null
@@ -1 +0,0 @@
-Reduce memory usage of sending dummy events.
diff --git a/changelog.d/13311.misc b/changelog.d/13311.misc
deleted file mode 100644
index 4be81c675c..0000000000
--- a/changelog.d/13311.misc
+++ /dev/null
@@ -1 +0,0 @@
-Prevent formatting changes of [#3679](https://github.com/matrix-org/synapse/pull/3679) from appearing in `git blame`.
\ No newline at end of file
diff --git a/changelog.d/13314.doc b/changelog.d/13314.doc
deleted file mode 100644
index 75c71ef27a..0000000000
--- a/changelog.d/13314.doc
+++ /dev/null
@@ -1 +0,0 @@
-Add notes when config options where changed. Contributed by @behrmann.
diff --git a/changelog.d/13318.misc b/changelog.d/13318.misc
deleted file mode 100644
index f5cd26b862..0000000000
--- a/changelog.d/13318.misc
+++ /dev/null
@@ -1 +0,0 @@
-Validate federation destinations and log an error if a destination is invalid.
diff --git a/changelog.d/13320.misc b/changelog.d/13320.misc
deleted file mode 100644
index d33cf3a25a..0000000000
--- a/changelog.d/13320.misc
+++ /dev/null
@@ -1 +0,0 @@
-Fix `FederationClient.get_pdu()` returning events from the cache as `outliers` instead of original events we saw over federation.
diff --git a/changelog.d/13323.misc b/changelog.d/13323.misc
deleted file mode 100644
index 3caa94a2f6..0000000000
--- a/changelog.d/13323.misc
+++ /dev/null
@@ -1 +0,0 @@
-Reduce memory usage of state caches.
diff --git a/changelog.d/13326.removal b/changelog.d/13326.removal
deleted file mode 100644
index 8112286671..0000000000
--- a/changelog.d/13326.removal
+++ /dev/null
@@ -1 +0,0 @@
-Stop builindg `.deb` packages for Ubuntu 21.10 (Impish Indri), which has reached end of life.
diff --git a/changelog.d/13328.misc b/changelog.d/13328.misc
deleted file mode 100644
index d15fb5fc37..0000000000
--- a/changelog.d/13328.misc
+++ /dev/null
@@ -1 +0,0 @@
-Add type hints to `trace` decorator.
diff --git a/changelog.d/13573.misc b/changelog.d/13573.misc
new file mode 100644
index 0000000000..1ce9c0c081
--- /dev/null
+++ b/changelog.d/13573.misc
@@ -0,0 +1 @@
+Cache user IDs instead of profiles to reduce cache memory usage. Contributed by Nick @ Beeper (@fizzadar).
diff --git a/changelog.d/13588.misc b/changelog.d/13588.misc
new file mode 100644
index 0000000000..eca1416ceb
--- /dev/null
+++ b/changelog.d/13588.misc
@@ -0,0 +1 @@
+Instrument `_check_sigs_and_hash_and_fetch` to trace time spent in child concurrent calls for understandable traces in Jaeger.
diff --git a/changelog.d/13591.misc b/changelog.d/13591.misc
new file mode 100644
index 0000000000..080e865e55
--- /dev/null
+++ b/changelog.d/13591.misc
@@ -0,0 +1 @@
+Improve performance of `@cachedList`.
diff --git a/changelog.d/13592.misc b/changelog.d/13592.misc
new file mode 100644
index 0000000000..8f48d557e5
--- /dev/null
+++ b/changelog.d/13592.misc
@@ -0,0 +1 @@
+Minor speed up of fetching large numbers of push rules.
diff --git a/changelog.d/13600.misc b/changelog.d/13600.misc
new file mode 100644
index 0000000000..1ce9c0c081
--- /dev/null
+++ b/changelog.d/13600.misc
@@ -0,0 +1 @@
+Cache user IDs instead of profiles to reduce cache memory usage. Contributed by Nick @ Beeper (@fizzadar).
diff --git a/changelog.d/13602.doc b/changelog.d/13602.doc
new file mode 100644
index 0000000000..dbba082163
--- /dev/null
+++ b/changelog.d/13602.doc
@@ -0,0 +1 @@
+Improve the description of the ["chain cover index"](https://matrix-org.github.io/synapse/latest/auth_chain_difference_algorithm.html) used internally by Synapse.
diff --git a/contrib/grafana/synapse.json b/contrib/grafana/synapse.json
index 819426b8ea..0f23fc17ea 100644
--- a/contrib/grafana/synapse.json
+++ b/contrib/grafana/synapse.json
@@ -9,17 +9,18 @@
       "pluginName": "Prometheus"
     }
   ],
+  "__elements": {},
   "__requires": [
     {
       "type": "grafana",
       "id": "grafana",
       "name": "Grafana",
-      "version": "7.3.7"
+      "version": "9.0.4"
     },
     {
       "type": "panel",
       "id": "graph",
-      "name": "Graph",
+      "name": "Graph (old)",
       "version": ""
     },
     {
@@ -33,13 +34,21 @@
       "id": "prometheus",
       "name": "Prometheus",
       "version": "1.0.0"
+    },
+    {
+      "type": "panel",
+      "id": "timeseries",
+      "name": "Time series",
+      "version": ""
     }
   ],
   "annotations": {
     "list": [
       {
         "builtIn": 1,
-        "datasource": "$datasource",
+        "datasource": {
+          "uid": "$datasource"
+        },
         "enable": false,
         "hide": true,
         "iconColor": "rgba(0, 211, 255, 1)",
@@ -51,10 +60,9 @@
     ]
   },
   "editable": true,
-  "gnetId": null,
+  "fiscalYearStartMonth": 0,
   "graphTooltip": 0,
   "id": null,
-  "iteration": 1628606819564,
   "links": [
     {
       "asDropdown": false,
@@ -66,24 +74,16 @@
       ],
       "title": "Dashboards",
       "type": "dashboards"
-    },
-    {
-      "asDropdown": false,
-      "icon": "external link",
-      "includeVars": false,
-      "keepTime": false,
-      "tags": [],
-      "targetBlank": true,
-      "title": "Synapse Documentation",
-      "tooltip": "Open Documentation",
-      "type": "link",
-      "url": "https://matrix-org.github.io/synapse/latest/"
     }
   ],
+  "liveNow": false,
   "panels": [
     {
       "collapsed": false,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
@@ -92,6 +92,15 @@
       },
       "id": 73,
       "panels": [],
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "000000001"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Overview",
       "type": "row"
     },
@@ -108,12 +117,8 @@
         "mode": "spectrum"
       },
       "dataFormat": "tsbuckets",
-      "datasource": "$datasource",
-      "fieldConfig": {
-        "defaults": {
-          "custom": {}
-        },
-        "overrides": []
+      "datasource": {
+        "uid": "$datasource"
       },
       "gridPos": {
         "h": 9,
@@ -132,6 +137,9 @@
       "reverseYBuckets": false,
       "targets": [
         {
+          "datasource": {
+            "uid": "$datasource"
+          },
           "expr": "sum(rate(synapse_http_server_response_time_seconds_bucket{servlet='RoomSendEventRestServlet',instance=\"$instance\",code=~\"2..\"}[$bucket_size])) by (le)",
           "format": "heatmap",
           "interval": "",
@@ -149,31 +157,24 @@
       "xAxis": {
         "show": true
       },
-      "xBucketNumber": null,
-      "xBucketSize": null,
       "yAxis": {
-        "decimals": null,
         "format": "s",
         "logBase": 2,
-        "max": null,
-        "min": null,
-        "show": true,
-        "splitFactor": null
+        "show": true
       },
-      "yBucketBound": "auto",
-      "yBucketNumber": null,
-      "yBucketSize": null
+      "yBucketBound": "auto"
     },
     {
       "aliasColors": {},
       "bars": false,
       "dashLength": 10,
       "dashes": false,
-      "datasource": "$datasource",
+      "datasource": {
+        "uid": "$datasource"
+      },
       "description": "",
       "fieldConfig": {
         "defaults": {
-          "custom": {},
           "links": []
         },
         "overrides": []
@@ -207,7 +208,7 @@
       },
       "paceLength": 10,
       "percentage": false,
-      "pluginVersion": "7.3.7",
+      "pluginVersion": "9.0.4",
       "pointradius": 5,
       "points": false,
       "renderer": "flot",
@@ -266,6 +267,9 @@
       "steppedLine": false,
       "targets": [
         {
+          "datasource": {
+            "uid": "$datasource"
+          },
           "expr": "histogram_quantile(0.99, sum(rate(synapse_http_server_response_time_seconds_bucket{servlet='RoomSendEventRestServlet',index=~\"$index\",instance=\"$instance\",code=~\"2..\"}[$bucket_size])) by (le))",
           "format": "time_series",
           "intervalFactor": 1,
@@ -273,6 +277,9 @@
           "refId": "D"
         },
         {
+          "datasource": {
+            "uid": "$datasource"
+          },
           "expr": "histogram_quantile(0.9, sum(rate(synapse_http_server_response_time_seconds_bucket{servlet='RoomSendEventRestServlet',index=~\"$index\",instance=\"$instance\",code=~\"2..\"}[$bucket_size])) by (le))",
           "format": "time_series",
           "interval": "",
@@ -281,6 +288,9 @@
           "refId": "A"
         },
         {
+          "datasource": {
+            "uid": "$datasource"
+          },
           "expr": "histogram_quantile(0.75, sum(rate(synapse_http_server_response_time_seconds_bucket{servlet='RoomSendEventRestServlet',index=~\"$index\",instance=\"$instance\",code=~\"2..\"}[$bucket_size])) by (le))",
           "format": "time_series",
           "intervalFactor": 1,
@@ -288,6 +298,9 @@
           "refId": "C"
         },
         {
+          "datasource": {
+            "uid": "$datasource"
+          },
           "expr": "histogram_quantile(0.5, sum(rate(synapse_http_server_response_time_seconds_bucket{servlet='RoomSendEventRestServlet',index=~\"$index\",instance=\"$instance\",code=~\"2..\"}[$bucket_size])) by (le))",
           "format": "time_series",
           "intervalFactor": 1,
@@ -295,21 +308,33 @@
           "refId": "B"
         },
         {
+          "datasource": {
+            "uid": "$datasource"
+          },
           "expr": "histogram_quantile(0.25, sum(rate(synapse_http_server_response_time_seconds_bucket{servlet='RoomSendEventRestServlet',index=~\"$index\",instance=\"$instance\",code=~\"2..\"}[$bucket_size])) by (le))",
           "legendFormat": "25%",
           "refId": "F"
         },
         {
+          "datasource": {
+            "uid": "$datasource"
+          },
           "expr": "histogram_quantile(0.05, sum(rate(synapse_http_server_response_time_seconds_bucket{servlet='RoomSendEventRestServlet',index=~\"$index\",instance=\"$instance\",code=~\"2..\"}[$bucket_size])) by (le))",
           "legendFormat": "5%",
           "refId": "G"
         },
         {
+          "datasource": {
+            "uid": "$datasource"
+          },
           "expr": "sum(rate(synapse_http_server_response_time_seconds_sum{servlet='RoomSendEventRestServlet',index=~\"$index\",instance=\"$instance\",code=~\"2..\"}[$bucket_size])) / sum(rate(synapse_http_server_response_time_seconds_count{servlet='RoomSendEventRestServlet',index=~\"$index\",instance=\"$instance\",code=~\"2..\"}[$bucket_size]))",
           "legendFormat": "Average",
           "refId": "H"
         },
         {
+          "datasource": {
+            "uid": "$datasource"
+          },
           "expr": "sum(rate(synapse_storage_events_persisted_events{instance=\"$instance\"}[$bucket_size]))",
           "hide": false,
           "instant": false,
@@ -319,6 +344,7 @@
       ],
       "thresholds": [
         {
+          "$$hashKey": "object:283",
           "colorMode": "warning",
           "fill": false,
           "line": true,
@@ -327,6 +353,7 @@
           "yaxis": "left"
         },
         {
+          "$$hashKey": "object:284",
           "colorMode": "critical",
           "fill": false,
           "line": true,
@@ -335,9 +362,7 @@
           "yaxis": "left"
         }
       ],
-      "timeFrom": null,
       "timeRegions": [],
-      "timeShift": null,
       "title": "Event Send Time Quantiles (excluding errors, all workers)",
       "tooltip": {
         "shared": true,
@@ -346,34 +371,30 @@
       },
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       "xaxis": {
-        "buckets": null,
         "mode": "time",
-        "name": null,
         "show": true,
         "values": []
       },
       "yaxes": [
         {
-          "decimals": null,
+          "$$hashKey": "object:255",
           "format": "s",
           "label": "",
           "logBase": 1,
-          "max": null,
           "min": "0",
           "show": true
         },
         {
+          "$$hashKey": "object:256",
           "format": "hertz",
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           "logBase": 1,
-          "max": null,
           "min": "0",
           "show": true
         }
       ],
       "yaxis": {
-        "align": false,
-        "alignLevel": null
+        "align": false
       }
     },
     {
@@ -381,10 +402,11 @@
       "bars": false,
       "dashLength": 10,
       "dashes": false,
-      "datasource": "$datasource",
+      "datasource": {
+        "uid": "$datasource"
+      },
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-          "custom": {},
           "links": []
         },
         "overrides": []
@@ -417,7 +439,7 @@
       },
       "paceLength": 10,
       "percentage": false,
-      "pluginVersion": "7.3.7",
+      "pluginVersion": "9.0.4",
       "pointradius": 5,
       "points": false,
       "renderer": "flot",
@@ -427,6 +449,9 @@
       "steppedLine": false,
       "targets": [
         {
+          "datasource": {
+            "uid": "$datasource"
+          },
           "expr": "rate(process_cpu_seconds_total{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
           "format": "time_series",
           "interval": "",
@@ -437,6 +462,7 @@
       ],
       "thresholds": [
         {
+          "$$hashKey": "object:566",
           "colorMode": "critical",
           "fill": true,
           "line": true,
@@ -445,9 +471,7 @@
           "yaxis": "left"
         }
       ],
-      "timeFrom": null,
       "timeRegions": [],
-      "timeShift": null,
       "title": "CPU usage",
       "tooltip": {
         "shared": false,
@@ -456,34 +480,28 @@
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       "type": "graph",
       "xaxis": {
-        "buckets": null,
         "mode": "time",
-        "name": null,
         "show": true,
         "values": []
       },
       "yaxes": [
         {
-          "decimals": null,
+          "$$hashKey": "object:538",
           "format": "percentunit",
-          "label": null,
           "logBase": 1,
           "max": "1.5",
           "min": "0",
           "show": true
         },
         {
+          "$$hashKey": "object:539",
           "format": "short",
-          "label": null,
           "logBase": 1,
-          "max": null,
-          "min": null,
           "show": true
         }
       ],
       "yaxis": {
-        "align": false,
-        "alignLevel": null
+        "align": false
       }
     },
     {
@@ -491,12 +509,13 @@
       "bars": false,
       "dashLength": 10,
       "dashes": false,
-      "datasource": "$datasource",
+      "datasource": {
+        "uid": "$datasource"
+      },
       "editable": true,
       "error": false,
       "fieldConfig": {
         "defaults": {
-          "custom": {},
           "links": []
         },
         "overrides": []
@@ -530,7 +549,7 @@
       },
       "paceLength": 10,
       "percentage": false,
-      "pluginVersion": "7.3.7",
+      "pluginVersion": "9.0.4",
       "pointradius": 5,
       "points": false,
       "renderer": "flot",
@@ -540,6 +559,9 @@
       "steppedLine": false,
       "targets": [
         {
+          "datasource": {
+            "uid": "$datasource"
+          },
           "expr": "process_resident_memory_bytes{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
           "format": "time_series",
           "interval": "",
@@ -550,6 +572,9 @@
           "target": ""
         },
         {
+          "datasource": {
+            "uid": "$datasource"
+          },
           "expr": "sum(process_resident_memory_bytes{instance=\"$instance\",job=~\"$job\",index=~\"$index\"})",
           "hide": true,
           "interval": "",
@@ -558,9 +583,7 @@
         }
       ],
       "thresholds": [],
-      "timeFrom": null,
       "timeRegions": [],
-      "timeShift": null,
       "title": "Memory",
       "tooltip": {
         "shared": false,
@@ -570,31 +593,27 @@
       "transformations": [],
       "type": "graph",
       "xaxis": {
-        "buckets": null,
         "mode": "time",
-        "name": null,
         "show": true,
         "values": []
       },
       "yaxes": [
         {
+          "$$hashKey": "object:1560",
           "format": "bytes",
           "logBase": 1,
-          "max": null,
           "min": "0",
           "show": true
         },
         {
+          "$$hashKey": "object:1561",
           "format": "short",
           "logBase": 1,
-          "max": null,
-          "min": null,
           "show": true
         }
       ],
       "yaxis": {
-        "align": false,
-        "alignLevel": null
+        "align": false
       }
     },
     {
@@ -602,10 +621,11 @@
       "bars": false,
       "dashLength": 10,
       "dashes": false,
-      "datasource": "$datasource",
+      "datasource": {
+        "uid": "$datasource"
+      },
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-          "custom": {},
           "links": []
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         "overrides": []
@@ -638,12 +658,13 @@
       },
       "paceLength": 10,
       "percentage": false,
-      "pluginVersion": "7.3.7",
+      "pluginVersion": "9.0.4",
       "pointradius": 5,
       "points": false,
       "renderer": "flot",
       "seriesOverrides": [
         {
+          "$$hashKey": "object:639",
           "alias": "/max$/",
           "color": "#890F02",
           "fill": 0,
@@ -655,6 +676,9 @@
       "steppedLine": false,
       "targets": [
         {
+          "datasource": {
+            "uid": "$datasource"
+          },
           "expr": "process_open_fds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
           "format": "time_series",
           "hide": false,
@@ -665,6 +689,9 @@
           "step": 20
         },
         {
+          "datasource": {
+            "uid": "$datasource"
+          },
           "expr": "process_max_fds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
           "format": "time_series",
           "hide": true,
@@ -676,9 +703,7 @@
         }
       ],
       "thresholds": [],
-      "timeFrom": null,
       "timeRegions": [],
-      "timeShift": null,
       "title": "Open FDs",
       "tooltip": {
         "shared": false,
@@ -687,40 +712,35 @@
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       "xaxis": {
-        "buckets": null,
         "mode": "time",
-        "name": null,
         "show": true,
         "values": []
       },
       "yaxes": [
         {
-          "decimals": null,
+          "$$hashKey": "object:650",
           "format": "none",
           "label": "",
           "logBase": 1,
-          "max": null,
-          "min": null,
           "show": true
         },
         {
-          "decimals": null,
+          "$$hashKey": "object:651",
           "format": "short",
-          "label": null,
           "logBase": 1,
-          "max": null,
-          "min": null,
           "show": true
         }
       ],
       "yaxis": {
-        "align": false,
-        "alignLevel": null
+        "align": false
       }
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "$datasource"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
@@ -734,12 +754,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "editable": true,
           "error": false,
           "fieldConfig": {
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-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -751,7 +772,7 @@
             "h": 7,
             "w": 12,
             "x": 0,
-            "y": 25
+            "y": 27
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           "id": 5,
@@ -777,15 +798,17 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
           "seriesOverrides": [
             {
+              "$$hashKey": "object:1240",
               "alias": "/user/"
             },
             {
+              "$$hashKey": "object:1241",
               "alias": "/system/"
             }
           ],
@@ -794,6 +817,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(process_cpu_system_seconds_total{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "intervalFactor": 1,
@@ -803,6 +829,9 @@
               "step": 20
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(process_cpu_user_seconds_total{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "hide": false,
@@ -815,6 +844,7 @@
           ],
           "thresholds": [
             {
+              "$$hashKey": "object:1278",
               "colorMode": "custom",
               "fillColor": "rgba(255, 255, 255, 1)",
               "line": true,
@@ -824,6 +854,7 @@
               "yaxis": "left"
             },
             {
+              "$$hashKey": "object:1279",
               "colorMode": "custom",
               "fillColor": "rgba(255, 255, 255, 1)",
               "line": true,
@@ -833,6 +864,7 @@
               "yaxis": "left"
             },
             {
+              "$$hashKey": "object:1498",
               "colorMode": "critical",
               "fill": true,
               "line": true,
@@ -841,9 +873,7 @@
               "yaxis": "left"
             }
           ],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "CPU",
           "tooltip": {
             "shared": false,
@@ -852,15 +882,13 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
-              "decimals": null,
+              "$$hashKey": "object:1250",
               "format": "percentunit",
               "label": "",
               "logBase": 1,
@@ -869,71 +897,113 @@
               "show": true
             },
             {
+              "$$hashKey": "object:1251",
               "format": "short",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
-          "aliasColors": {},
-          "bars": false,
-          "dashLength": 10,
-          "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "type": "prometheus",
+            "uid": "${DS_PROMETHEUS}"
+          },
           "description": "Shows the time in which the given percentage of reactor ticks completed, over the sampled timespan",
           "fieldConfig": {
             "defaults": {
-              "custom": {},
-              "links": []
+              "color": {
+                "mode": "palette-classic"
+              },
+              "custom": {
+                "axisLabel": "",
+                "axisPlacement": "auto",
+                "barAlignment": 0,
+                "drawStyle": "line",
+                "fillOpacity": 10,
+                "gradientMode": "none",
+                "hideFrom": {
+                  "legend": false,
+                  "tooltip": false,
+                  "viz": false
+                },
+                "lineInterpolation": "linear",
+                "lineWidth": 1,
+                "pointSize": 5,
+                "scaleDistribution": {
+                  "type": "linear"
+                },
+                "showPoints": "never",
+                "spanNulls": true,
+                "stacking": {
+                  "group": "A",
+                  "mode": "none"
+                },
+                "thresholdsStyle": {
+                  "mode": "off"
+                }
+              },
+              "links": [],
+              "mappings": [],
+              "thresholds": {
+                "mode": "absolute",
+                "steps": [
+                  {
+                    "color": "green"
+                  },
+                  {
+                    "color": "red",
+                    "value": 80
+                  }
+                ]
+              },
+              "unit": "s"
             },
             "overrides": []
           },
-          "fill": 1,
-          "fillGradient": 0,
           "gridPos": {
             "h": 7,
             "w": 12,
             "x": 12,
-            "y": 25
+            "y": 27
           },
-          "hiddenSeries": false,
           "id": 105,
           "interval": "",
-          "legend": {
-            "avg": false,
-            "current": false,
-            "max": false,
-            "min": false,
-            "show": true,
-            "total": false,
-            "values": false
-          },
-          "lines": true,
-          "linewidth": 1,
           "links": [],
-          "nullPointMode": "null",
           "options": {
-            "alertThreshold": true
+            "legend": {
+              "calcs": [],
+              "displayMode": "list",
+              "placement": "bottom"
+            },
+            "tooltip": {
+              "mode": "single",
+              "sort": "none"
+            }
           },
-          "paceLength": 10,
-          "percentage": false,
-          "pluginVersion": "7.3.7",
-          "pointradius": 5,
-          "points": false,
-          "renderer": "flot",
-          "seriesOverrides": [],
-          "spaceLength": 10,
-          "stack": false,
-          "steppedLine": false,
+          "pluginVersion": "8.3.2",
           "targets": [
             {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
+              "exemplar": true,
+              "expr": "histogram_quantile(0.999, rate(python_twisted_reactor_tick_time_bucket{index=~\"$index\",instance=\"$instance\",job=~\"$job\"}[$bucket_size]))",
+              "hide": false,
+              "interval": "",
+              "legendFormat": "{{job}}-{{index}} 99.9%",
+              "refId": "E"
+            },
+            {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
+              "exemplar": true,
               "expr": "histogram_quantile(0.99, rate(python_twisted_reactor_tick_time_bucket{index=~\"$index\",instance=\"$instance\",job=~\"$job\"}[$bucket_size]))",
               "format": "time_series",
               "interval": "",
@@ -943,13 +1013,23 @@
               "step": 20
             },
             {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
+              "exemplar": true,
               "expr": "histogram_quantile(0.95, rate(python_twisted_reactor_tick_time_bucket{index=~\"$index\",instance=\"$instance\",job=~\"$job\"}[$bucket_size]))",
               "format": "time_series",
+              "interval": "",
               "intervalFactor": 1,
               "legendFormat": "{{job}}-{{index}} 95%",
               "refId": "B"
             },
             {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
               "expr": "histogram_quantile(0.90, rate(python_twisted_reactor_tick_time_bucket{index=~\"$index\",instance=\"$instance\",job=~\"$job\"}[$bucket_size]))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -957,6 +1037,10 @@
               "refId": "C"
             },
             {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
               "expr": "rate(python_twisted_reactor_tick_time_sum{index=~\"$index\",instance=\"$instance\",job=~\"$job\"}[$bucket_size]) / rate(python_twisted_reactor_tick_time_count{index=~\"$index\",instance=\"$instance\",job=~\"$job\"}[$bucket_size])",
               "format": "time_series",
               "intervalFactor": 1,
@@ -964,58 +1048,21 @@
               "refId": "D"
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           ],
-          "thresholds": [],
-          "timeFrom": null,
-          "timeRegions": [],
-          "timeShift": null,
           "title": "Reactor tick quantiles",
-          "tooltip": {
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-            "sort": 0,
-            "value_type": "individual"
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-          "xaxis": {
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-            "mode": "time",
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-            "show": true,
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-              "min": null,
-              "show": false
-            }
-          ],
-          "yaxis": {
-            "align": false,
-            "alignLevel": null
-          }
+          "type": "timeseries"
         },
         {
           "aliasColors": {},
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
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           "error": false,
           "fieldConfig": {
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@@ -1027,7 +1074,7 @@
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+            "y": 34
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@@ -1049,7 +1096,7 @@
           },
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           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -1059,6 +1106,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "process_resident_memory_bytes{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
               "format": "time_series",
               "interval": "",
@@ -1069,6 +1119,9 @@
               "target": ""
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(process_resident_memory_bytes{instance=\"$instance\",job=~\"$job\",index=~\"$index\"})",
               "interval": "",
               "legendFormat": "total",
@@ -1076,9 +1129,7 @@
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-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Memory",
           "tooltip": {
             "shared": false,
@@ -1088,9 +1139,7 @@
           "transformations": [],
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
@@ -1098,21 +1147,17 @@
             {
               "format": "bytes",
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             },
             {
               "format": "short",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -1120,10 +1165,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -1134,7 +1180,7 @@
             "h": 7,
             "w": 12,
             "x": 12,
-            "y": 32
+            "y": 34
           },
           "hiddenSeries": false,
           "id": 49,
@@ -1156,7 +1202,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -1172,6 +1218,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "scrape_duration_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
               "format": "time_series",
               "interval": "",
@@ -1182,9 +1231,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Prometheus scrape time",
           "tooltip": {
             "shared": false,
@@ -1193,18 +1240,14 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
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           "yaxes": [
             {
               "format": "s",
-              "label": null,
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             },
@@ -1219,8 +1262,7 @@
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -1228,10 +1270,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -1242,7 +1285,7 @@
             "h": 7,
             "w": 12,
             "x": 0,
-            "y": 39
+            "y": 41
           },
           "hiddenSeries": false,
           "id": 53,
@@ -1264,7 +1307,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -1274,6 +1317,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "min_over_time(up{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "intervalFactor": 2,
@@ -1282,9 +1328,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Up",
           "tooltip": {
             "shared": false,
@@ -1293,33 +1337,24 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
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               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -1327,10 +1362,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -1341,7 +1377,7 @@
             "h": 7,
             "w": 12,
             "x": 12,
-            "y": 39
+            "y": 41
           },
           "hiddenSeries": false,
           "id": 120,
@@ -1362,7 +1398,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 2,
           "points": false,
           "renderer": "flot",
@@ -1372,6 +1408,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_http_server_response_ru_utime_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])+rate(synapse_http_server_response_ru_stime_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "hide": false,
@@ -1381,6 +1420,9 @@
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_background_process_ru_utime_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])+rate(synapse_background_process_ru_stime_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "hide": false,
@@ -1401,9 +1443,7 @@
               "yaxis": "left"
             }
           ],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Stacked CPU usage",
           "tooltip": {
             "shared": false,
@@ -1412,33 +1452,26 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
+              "$$hashKey": "object:572",
               "format": "percentunit",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
+              "$$hashKey": "object:573",
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -1446,10 +1479,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -1460,7 +1494,7 @@
             "h": 7,
             "w": 12,
             "x": 0,
-            "y": 46
+            "y": 48
           },
           "hiddenSeries": false,
           "id": 136,
@@ -1481,7 +1515,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 2,
           "points": false,
           "renderer": "flot",
@@ -1491,20 +1525,24 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_http_client_requests{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
               "legendFormat": "{{job}}-{{index}} {{method}}",
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_http_matrixfederationclient_requests{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
               "legendFormat": "{{job}}-{{index}} {{method}} (federation)",
               "refId": "B"
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Outgoing HTTP request rate",
           "tooltip": {
             "shared": false,
@@ -1513,43 +1551,133 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "reqps",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
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             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
+        },
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "${DS_PROMETHEUS}"
+          },
+          "fieldConfig": {
+            "defaults": {
+              "color": {
+                "mode": "palette-classic"
+              },
+              "custom": {
+                "axisLabel": "active threads",
+                "axisPlacement": "auto",
+                "barAlignment": 0,
+                "drawStyle": "line",
+                "fillOpacity": 0,
+                "gradientMode": "none",
+                "hideFrom": {
+                  "legend": false,
+                  "tooltip": false,
+                  "viz": false
+                },
+                "lineInterpolation": "linear",
+                "lineWidth": 1,
+                "pointSize": 5,
+                "scaleDistribution": {
+                  "type": "linear"
+                },
+                "showPoints": "auto",
+                "spanNulls": false,
+                "stacking": {
+                  "group": "A",
+                  "mode": "none"
+                },
+                "thresholdsStyle": {
+                  "mode": "off"
+                }
+              },
+              "mappings": [],
+              "thresholds": {
+                "mode": "absolute",
+                "steps": [
+                  {
+                    "color": "green"
+                  },
+                  {
+                    "color": "red",
+                    "value": 80
+                  }
+                ]
+              }
+            },
+            "overrides": []
+          },
+          "gridPos": {
+            "h": 7,
+            "w": 12,
+            "x": 12,
+            "y": 48
+          },
+          "id": 207,
+          "options": {
+            "legend": {
+              "calcs": [],
+              "displayMode": "list",
+              "placement": "bottom"
+            },
+            "tooltip": {
+              "mode": "single",
+              "sort": "none"
+            }
+          },
+          "targets": [
+            {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
+              "exemplar": true,
+              "expr": "synapse_threadpool_working_threads{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
+              "interval": "",
+              "legendFormat": "{{job}}-{{index}} {{name}}",
+              "refId": "A"
+            }
+          ],
+          "title": "Threadpool activity",
+          "type": "timeseries"
+        }
+      ],
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "$datasource"
+          },
+          "refId": "A"
         }
       ],
-      "repeat": null,
       "title": "Process info",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "$datasource"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
@@ -1571,18 +1699,14 @@
             "mode": "spectrum"
           },
           "dataFormat": "tsbuckets",
-          "datasource": "$datasource",
-          "fieldConfig": {
-            "defaults": {
-              "custom": {}
-            },
-            "overrides": []
+          "datasource": {
+            "uid": "$datasource"
           },
           "gridPos": {
             "h": 9,
             "w": 12,
             "x": 0,
-            "y": 21
+            "y": 28
           },
           "heatmap": {},
           "hideZeroBuckets": false,
@@ -1595,6 +1719,9 @@
           "reverseYBuckets": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_http_server_response_time_seconds_bucket{servlet='RoomSendEventRestServlet',instance=\"$instance\"}[$bucket_size])) by (le)",
               "format": "heatmap",
               "intervalFactor": 1,
@@ -1611,33 +1738,26 @@
           "xAxis": {
             "show": true
           },
-          "xBucketNumber": null,
-          "xBucketSize": null,
           "yAxis": {
-            "decimals": null,
             "format": "s",
             "logBase": 2,
-            "max": null,
-            "min": null,
-            "show": true,
-            "splitFactor": null
+            "show": true
           },
-          "yBucketBound": "auto",
-          "yBucketNumber": null,
-          "yBucketSize": null
+          "yBucketBound": "auto"
         },
         {
           "aliasColors": {},
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "description": "",
           "editable": true,
           "error": false,
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -1649,7 +1769,7 @@
             "h": 9,
             "w": 12,
             "x": 12,
-            "y": 21
+            "y": 28
           },
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           "id": 33,
@@ -1671,7 +1791,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -1681,6 +1801,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_storage_events_persisted_events{instance=\"$instance\"}[$bucket_size])) without (job,index)",
               "format": "time_series",
               "interval": "",
@@ -1692,9 +1815,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Events Persisted (all workers)",
           "tooltip": {
             "shared": true,
@@ -1703,31 +1824,26 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
+              "$$hashKey": "object:102",
               "format": "hertz",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
+              "$$hashKey": "object:103",
               "format": "short",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -1735,21 +1851,17 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
-          "decimals": 1,
-          "fieldConfig": {
-            "defaults": {
-              "custom": {}
-            },
-            "overrides": []
+          "datasource": {
+            "uid": "$datasource"
           },
+          "decimals": 1,
           "fill": 1,
           "fillGradient": 0,
           "gridPos": {
             "h": 7,
             "w": 12,
             "x": 0,
-            "y": 30
+            "y": 37
           },
           "hiddenSeries": false,
           "id": 40,
@@ -1770,7 +1882,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -1780,6 +1892,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_storage_events_persisted_by_source_type{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "intervalFactor": 2,
@@ -1788,9 +1903,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Events/s Local vs Remote",
           "tooltip": {
             "shared": true,
@@ -1799,9 +1912,7 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
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@@ -1810,22 +1921,17 @@
               "format": "hertz",
               "label": "",
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
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-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -1833,21 +1939,17 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
-          "decimals": 1,
-          "fieldConfig": {
-            "defaults": {
-              "custom": {}
-            },
-            "overrides": []
+          "datasource": {
+            "uid": "$datasource"
           },
+          "decimals": 1,
           "fill": 1,
           "fillGradient": 0,
           "gridPos": {
             "h": 7,
             "w": 12,
             "x": 12,
-            "y": 30
+            "y": 37
           },
           "hiddenSeries": false,
           "id": 46,
@@ -1868,7 +1970,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -1878,6 +1980,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_storage_events_persisted_by_event_type{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
               "format": "time_series",
               "instant": false,
@@ -1888,9 +1993,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Events/s by Type",
           "tooltip": {
             "shared": false,
@@ -1899,33 +2002,25 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
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               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -1935,21 +2030,17 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
-          "decimals": 1,
-          "fieldConfig": {
-            "defaults": {
-              "custom": {}
-            },
-            "overrides": []
+          "datasource": {
+            "uid": "$datasource"
           },
+          "decimals": 1,
           "fill": 1,
           "fillGradient": 0,
           "gridPos": {
             "h": 7,
             "w": 12,
             "x": 0,
-            "y": 37
+            "y": 44
           },
           "hiddenSeries": false,
           "id": 44,
@@ -1973,7 +2064,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -1983,6 +2074,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_storage_events_persisted_by_origin{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
               "format": "time_series",
               "intervalFactor": 2,
@@ -1992,9 +2086,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Events/s by Origin",
           "tooltip": {
             "shared": false,
@@ -2003,33 +2095,25 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
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               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -2037,21 +2121,17 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
-          "decimals": 1,
-          "fieldConfig": {
-            "defaults": {
-              "custom": {}
-            },
-            "overrides": []
+          "datasource": {
+            "uid": "$datasource"
           },
+          "decimals": 1,
           "fill": 1,
           "fillGradient": 0,
           "gridPos": {
             "h": 7,
             "w": 12,
             "x": 12,
-            "y": 37
+            "y": 44
           },
           "hiddenSeries": false,
           "id": 45,
@@ -2075,7 +2155,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -2085,6 +2165,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_storage_events_persisted_events_sep{job=~\"$job\",index=~\"$index\", type=\"m.room.member\",instance=\"$instance\", origin_type=\"local\"}[$bucket_size])) by (origin_type, origin_entity)",
               "format": "time_series",
               "intervalFactor": 2,
@@ -2094,9 +2177,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Memberships/s by Origin",
           "tooltip": {
             "shared": true,
@@ -2105,33 +2186,25 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -2139,10 +2212,12 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "type": "prometheus",
+            "uid": "${DS_PROMETHEUS}"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -2153,7 +2228,7 @@
             "h": 9,
             "w": 12,
             "x": 0,
-            "y": 44
+            "y": 51
           },
           "hiddenSeries": false,
           "id": 118,
@@ -2175,7 +2250,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -2191,6 +2266,11 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
+              "exemplar": true,
               "expr": "histogram_quantile(0.99, sum(rate(synapse_http_server_response_time_seconds_bucket{servlet='RoomSendEventRestServlet',instance=\"$instance\",code=~\"2..\",job=~\"$job\",index=~\"$index\"}[$bucket_size])) without (method))",
               "format": "time_series",
               "interval": "",
@@ -2199,6 +2279,10 @@
               "refId": "A"
             },
             {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
               "expr": "histogram_quantile(0.95, sum(rate(synapse_http_server_response_time_seconds_bucket{servlet='RoomSendEventRestServlet',instance=\"$instance\",code=~\"2..\",job=~\"$job\",index=~\"$index\"}[$bucket_size])) without (method))",
               "format": "time_series",
               "interval": "",
@@ -2207,6 +2291,10 @@
               "refId": "B"
             },
             {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
               "expr": "histogram_quantile(0.90, sum(rate(synapse_http_server_response_time_seconds_bucket{servlet='RoomSendEventRestServlet',instance=\"$instance\",code=~\"2..\",job=~\"$job\",index=~\"$index\"}[$bucket_size])) without (method))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -2214,6 +2302,10 @@
               "refId": "C"
             },
             {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
               "expr": "histogram_quantile(0.50, sum(rate(synapse_http_server_response_time_seconds_bucket{servlet='RoomSendEventRestServlet',instance=\"$instance\",code=~\"2..\",job=~\"$job\",index=~\"$index\"}[$bucket_size])) without (method))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -2221,6 +2313,10 @@
               "refId": "D"
             },
             {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
               "expr": "sum(rate(synapse_http_server_response_time_seconds_sum{servlet='RoomSendEventRestServlet',instance=\"$instance\",code=~\"2..\",job=~\"$job\",index=~\"$index\"}[$bucket_size])) without (method) / sum(rate(synapse_http_server_response_time_seconds_count{servlet='RoomSendEventRestServlet',instance=\"$instance\",code=~\"2..\",job=~\"$job\",index=~\"$index\"}[$bucket_size])) without (method)",
               "format": "time_series",
               "intervalFactor": 1,
@@ -2229,9 +2325,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Event send time quantiles by worker",
           "tooltip": {
             "shared": true,
@@ -2240,43 +2334,154 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
+              "$$hashKey": "object:263",
               "format": "s",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
+              "$$hashKey": "object:264",
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
+        },
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "$datasource"
+          },
+          "description": "CPU and DB time spent on most expensive state resolution in a room, summed over all workers. This is a very rough proxy for \"how fast is state res\", but it doesn't accurately represent the system load (e.g. it completely ignores cheap state resolutions).\n",
+          "fieldConfig": {
+            "defaults": {
+              "color": {
+                "mode": "palette-classic"
+              },
+              "custom": {
+                "axisLabel": "",
+                "axisPlacement": "auto",
+                "barAlignment": 0,
+                "drawStyle": "line",
+                "fillOpacity": 30,
+                "gradientMode": "none",
+                "hideFrom": {
+                  "legend": false,
+                  "tooltip": false,
+                  "viz": false
+                },
+                "lineInterpolation": "linear",
+                "lineWidth": 1,
+                "pointSize": 5,
+                "scaleDistribution": {
+                  "type": "linear"
+                },
+                "showPoints": "auto",
+                "spanNulls": false,
+                "stacking": {
+                  "group": "A",
+                  "mode": "normal"
+                },
+                "thresholdsStyle": {
+                  "mode": "off"
+                }
+              },
+              "mappings": [],
+              "thresholds": {
+                "mode": "absolute",
+                "steps": [
+                  {
+                    "color": "green"
+                  },
+                  {
+                    "color": "red",
+                    "value": 80
+                  }
+                ]
+              },
+              "unit": "s/s"
+            },
+            "overrides": []
+          },
+          "gridPos": {
+            "h": 9,
+            "w": 12,
+            "x": 12,
+            "y": 51
+          },
+          "id": 222,
+          "options": {
+            "legend": {
+              "calcs": [],
+              "displayMode": "hidden",
+              "placement": "bottom"
+            },
+            "tooltip": {
+              "mode": "multi",
+              "sort": "none"
+            }
+          },
+          "targets": [
+            {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "$datasource"
+              },
+              "exemplar": false,
+              "expr": "sum(rate(synapse_state_res_db_for_biggest_room_seconds{instance=\"$instance\"}[1m]))",
+              "format": "time_series",
+              "hide": false,
+              "instant": false,
+              "interval": "",
+              "legendFormat": "DB time",
+              "refId": "B"
+            },
+            {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "$datasource"
+              },
+              "exemplar": false,
+              "expr": "sum(rate(synapse_state_res_cpu_for_biggest_room_seconds{instance=\"$instance\"}[1m]))",
+              "format": "time_series",
+              "hide": false,
+              "instant": false,
+              "interval": "",
+              "legendFormat": "CPU time",
+              "refId": "C"
+            }
+          ],
+          "title": "Stateres worst-case",
+          "type": "timeseries"
+        }
+      ],
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "$datasource"
+          },
+          "refId": "A"
         }
       ],
-      "repeat": null,
       "title": "Event persistence",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "$datasource"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
@@ -2290,13 +2495,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
-          "decimals": null,
+          "datasource": {
+            "uid": "$datasource"
+          },
           "editable": true,
           "error": false,
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -2308,7 +2513,7 @@
             "h": 8,
             "w": 12,
             "x": 0,
-            "y": 31
+            "y": 29
           },
           "hiddenSeries": false,
           "id": 4,
@@ -2333,7 +2538,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -2343,6 +2548,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_http_server_requests_received{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "interval": "",
@@ -2370,9 +2578,7 @@
               "yaxis": "left"
             }
           ],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Request Count by arrival time",
           "tooltip": {
             "shared": false,
@@ -2381,9 +2587,7 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
@@ -2391,21 +2595,16 @@
             {
               "format": "hertz",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -2413,12 +2612,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "editable": true,
           "error": false,
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -2430,7 +2630,7 @@
             "h": 8,
             "w": 12,
             "x": 12,
-            "y": 31
+            "y": 29
           },
           "hiddenSeries": false,
           "id": 32,
@@ -2451,7 +2651,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -2461,6 +2661,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_http_server_requests_received{instance=\"$instance\",job=~\"$job\",index=~\"$index\",method!=\"OPTIONS\"}[$bucket_size]) and topk(10,synapse_http_server_requests_received{instance=\"$instance\",job=~\"$job\",method!=\"OPTIONS\"})",
               "format": "time_series",
               "intervalFactor": 2,
@@ -2471,9 +2674,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Top 10 Request Counts",
           "tooltip": {
             "shared": false,
@@ -2482,9 +2683,7 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
@@ -2492,21 +2691,16 @@
             {
               "format": "hertz",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -2514,13 +2708,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
-          "decimals": null,
+          "datasource": {
+            "uid": "$datasource"
+          },
           "editable": true,
           "error": false,
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -2532,7 +2726,7 @@
             "h": 8,
             "w": 12,
             "x": 0,
-            "y": 39
+            "y": 37
           },
           "hiddenSeries": false,
           "id": 139,
@@ -2557,7 +2751,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -2567,6 +2761,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_http_server_in_flight_requests_ru_utime_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])+rate(synapse_http_server_in_flight_requests_ru_stime_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "interval": "",
@@ -2594,9 +2791,7 @@
               "yaxis": "left"
             }
           ],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Total CPU Usage by Endpoint",
           "tooltip": {
             "shared": false,
@@ -2605,9 +2800,7 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
@@ -2615,21 +2808,16 @@
             {
               "format": "percentunit",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -2637,13 +2825,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
-          "decimals": null,
+          "datasource": {
+            "uid": "$datasource"
+          },
           "editable": true,
           "error": false,
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -2655,7 +2843,7 @@
             "h": 8,
             "w": 12,
             "x": 12,
-            "y": 39
+            "y": 37
           },
           "hiddenSeries": false,
           "id": 52,
@@ -2680,7 +2868,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -2690,6 +2878,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "(rate(synapse_http_server_in_flight_requests_ru_utime_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])+rate(synapse_http_server_in_flight_requests_ru_stime_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])) / rate(synapse_http_server_requests_received{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "interval": "",
@@ -2717,9 +2908,7 @@
               "yaxis": "left"
             }
           ],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Average CPU Usage by Endpoint",
           "tooltip": {
             "shared": false,
@@ -2728,9 +2917,7 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
@@ -2738,21 +2925,16 @@
             {
               "format": "s",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -2760,12 +2942,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "editable": true,
           "error": false,
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -2777,7 +2960,7 @@
             "h": 8,
             "w": 12,
             "x": 0,
-            "y": 47
+            "y": 45
           },
           "hiddenSeries": false,
           "id": 7,
@@ -2801,7 +2984,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -2811,6 +2994,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_http_server_in_flight_requests_db_txn_duration_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "interval": "",
@@ -2821,9 +3007,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "DB Usage by endpoint",
           "tooltip": {
             "shared": false,
@@ -2832,9 +3016,7 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
@@ -2842,21 +3024,16 @@
             {
               "format": "percentunit",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -2864,13 +3041,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
-          "decimals": null,
+          "datasource": {
+            "uid": "$datasource"
+          },
           "editable": true,
           "error": false,
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -2882,7 +3059,7 @@
             "h": 8,
             "w": 12,
             "x": 12,
-            "y": 47
+            "y": 45
           },
           "hiddenSeries": false,
           "id": 47,
@@ -2907,7 +3084,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -2917,6 +3094,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "(sum(rate(synapse_http_server_response_time_seconds_sum{instance=\"$instance\",job=~\"$job\",index=~\"$index\",tag!=\"incremental_sync\"}[$bucket_size])) without (code))/(sum(rate(synapse_http_server_response_time_seconds_count{instance=\"$instance\",job=~\"$job\",index=~\"$index\",tag!=\"incremental_sync\"}[$bucket_size])) without (code))",
               "format": "time_series",
               "hide": false,
@@ -2928,9 +3108,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Non-sync avg response time",
           "tooltip": {
             "shared": false,
@@ -2939,9 +3117,7 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
@@ -2949,21 +3125,16 @@
             {
               "format": "s",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": false
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -2971,10 +3142,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -2985,7 +3157,7 @@
             "h": 9,
             "w": 12,
             "x": 0,
-            "y": 55
+            "y": 53
           },
           "hiddenSeries": false,
           "id": 103,
@@ -3006,7 +3178,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -3023,6 +3195,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "topk(10,synapse_http_server_in_flight_requests_count{instance=\"$instance\",job=~\"$job\",index=~\"$index\"})",
               "format": "time_series",
               "interval": "",
@@ -3031,6 +3206,9 @@
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(avg_over_time(synapse_http_server_in_flight_requests_count{job=\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size]))",
               "interval": "",
               "legendFormat": "Total",
@@ -3038,9 +3216,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Requests in flight",
           "tooltip": {
             "shared": false,
@@ -3049,43 +3225,45 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         }
       ],
-      "repeat": null,
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "$datasource"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Requests",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "$datasource"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
@@ -3099,10 +3277,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -3113,7 +3292,7 @@
             "h": 9,
             "w": 12,
             "x": 0,
-            "y": 32
+            "y": 5
           },
           "hiddenSeries": false,
           "id": 99,
@@ -3130,9 +3309,12 @@
           "linewidth": 1,
           "links": [],
           "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.1.3",
+          "pluginVersion": "8.4.3",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -3142,6 +3324,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_background_process_ru_utime_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])+rate(synapse_background_process_ru_stime_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "interval": "",
@@ -3151,9 +3336,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "CPU usage by background jobs",
           "tooltip": {
             "shared": false,
@@ -3162,33 +3345,24 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "percentunit",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -3196,10 +3370,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -3210,7 +3385,7 @@
             "h": 9,
             "w": 12,
             "x": 12,
-            "y": 32
+            "y": 5
           },
           "hiddenSeries": false,
           "id": 101,
@@ -3227,9 +3402,12 @@
           "linewidth": 1,
           "links": [],
           "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.1.3",
+          "pluginVersion": "8.4.3",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -3239,6 +3417,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_background_process_db_txn_duration_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]) +  rate(synapse_background_process_db_sched_duration_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "hide": false,
@@ -3248,9 +3429,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "DB usage by background jobs (including scheduling time)",
           "tooltip": {
             "shared": false,
@@ -3259,33 +3438,24 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "percentunit",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -3293,10 +3463,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -3307,7 +3478,7 @@
             "h": 8,
             "w": 12,
             "x": 0,
-            "y": 41
+            "y": 14
           },
           "hiddenSeries": false,
           "id": 138,
@@ -3323,8 +3494,11 @@
           "lines": true,
           "linewidth": 1,
           "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
           "percentage": false,
-          "pluginVersion": "7.1.3",
+          "pluginVersion": "8.4.3",
           "pointradius": 2,
           "points": false,
           "renderer": "flot",
@@ -3334,15 +3508,16 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_background_process_in_flight_count{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}",
               "legendFormat": "{{job}}-{{index}} {{name}}",
               "refId": "A"
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Background jobs in flight",
           "tooltip": {
             "shared": false,
@@ -3351,42 +3526,45 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         }
       ],
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "$datasource"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Background jobs",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "$datasource"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
@@ -3400,10 +3578,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -3436,7 +3615,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "8.4.3",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -3446,6 +3625,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_federation_client_sent_transactions{instance=\"$instance\"}[$bucket_size]))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -3453,15 +3635,16 @@
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_util_metrics_block_count{block_name=\"_send_new_transaction\",instance=\"$instance\"}[$bucket_size]) - ignoring (block_name) rate(synapse_federation_client_sent_transactions{instance=\"$instance\"}[$bucket_size]))",
               "legendFormat": "failed txn rate",
               "refId": "B"
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Outgoing federation transaction rate",
           "tooltip": {
             "shared": true,
@@ -3470,33 +3653,24 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -3504,10 +3678,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -3540,7 +3715,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "8.4.3",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -3550,6 +3725,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_federation_server_received_pdus{instance=~\"$instance\"}[$bucket_size]))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -3557,6 +3735,9 @@
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_federation_server_received_edus{instance=~\"$instance\"}[$bucket_size]))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -3565,9 +3746,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Incoming PDU/EDU rate",
           "tooltip": {
             "shared": true,
@@ -3576,33 +3755,24 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -3610,10 +3780,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -3646,7 +3817,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "8.4.3",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -3656,6 +3827,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_federation_client_sent_pdu_destinations:total{instance=\"$instance\"}[$bucket_size]))",
               "format": "time_series",
               "interval": "",
@@ -3664,6 +3838,9 @@
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_federation_client_sent_edus{instance=\"$instance\"}[$bucket_size]))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -3672,9 +3849,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Outgoing PDU/EDU rate",
           "tooltip": {
             "shared": true,
@@ -3683,33 +3858,24 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -3717,10 +3883,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -3753,7 +3920,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "8.4.3",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -3763,6 +3930,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_federation_client_sent_edus_by_type{instance=\"$instance\"}[$bucket_size])",
               "format": "time_series",
               "interval": "",
@@ -3772,9 +3942,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Outgoing EDUs by type",
           "tooltip": {
             "shared": true,
@@ -3783,33 +3951,24 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -3817,11 +3976,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "${DS_PROMETHEUS}",
+          "datasource": {
+            "type": "prometheus",
+            "uid": "$datasource"
+          },
           "description": "The number of events in the in-memory queues ",
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -3852,7 +4013,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "8.4.3",
           "pointradius": 2,
           "points": false,
           "renderer": "flot",
@@ -3862,12 +4023,20 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "$datasource"
+              },
               "expr": "synapse_federation_transaction_queue_pending_pdus{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
               "interval": "",
               "legendFormat": "pending PDUs {{job}}-{{index}}",
               "refId": "A"
             },
             {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "$datasource"
+              },
               "expr": "synapse_federation_transaction_queue_pending_edus{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
               "interval": "",
               "legendFormat": "pending EDUs {{job}}-{{index}}",
@@ -3875,9 +4044,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "In-memory federation transmission queues",
           "tooltip": {
             "shared": true,
@@ -3886,9 +4053,7 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
@@ -3897,7 +4062,6 @@
               "format": "short",
               "label": "events",
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             },
@@ -3905,14 +4069,11 @@
               "format": "short",
               "label": "",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
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         {
@@ -3920,11 +4081,12 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "description": "Number of events queued up on the master process for processing by the federation sender",
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             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -3957,7 +4119,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "8.4.3",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -3967,6 +4129,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_federation_send_queue_presence_changed_size{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
               "format": "time_series",
               "interval": "",
@@ -3975,6 +4140,9 @@
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_federation_send_queue_presence_map_size{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
               "format": "time_series",
               "hide": false,
@@ -3984,6 +4152,9 @@
               "refId": "B"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_federation_send_queue_presence_destinations_size{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
               "format": "time_series",
               "hide": false,
@@ -3993,6 +4164,9 @@
               "refId": "E"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_federation_send_queue_keyed_edu_size{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
               "format": "time_series",
               "hide": false,
@@ -4002,6 +4176,9 @@
               "refId": "C"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_federation_send_queue_edus_size{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
               "format": "time_series",
               "hide": false,
@@ -4011,6 +4188,9 @@
               "refId": "D"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_federation_send_queue_pos_time_size{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
               "format": "time_series",
               "hide": false,
@@ -4021,9 +4201,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Outgoing EDU queues on master",
           "tooltip": {
             "shared": true,
@@ -4032,39 +4210,30 @@
           },
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-            "buckets": null,
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-            "name": null,
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-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
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         {
           "cards": {
-            "cardPadding": -1,
-            "cardRound": null
+            "cardPadding": -1
           },
           "color": {
             "cardColor": "#b4ff00",
@@ -4075,12 +4244,8 @@
             "mode": "spectrum"
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           "dataFormat": "tsbuckets",
-          "datasource": "$datasource",
-          "fieldConfig": {
-            "defaults": {
-              "custom": {}
-            },
-            "overrides": []
+          "datasource": {
+            "uid": "$datasource"
           },
           "gridPos": {
             "h": 9,
@@ -4099,6 +4264,9 @@
           "reverseYBuckets": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_event_processing_lag_by_event_bucket{instance=\"$instance\",name=\"federation_sender\"}[$bucket_size])) by (le)",
               "format": "heatmap",
               "instant": false,
@@ -4118,30 +4286,24 @@
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-          "xBucketNumber": null,
-          "xBucketSize": null,
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             "decimals": 0,
             "format": "s",
             "logBase": 1,
-            "max": null,
-            "min": null,
-            "show": true,
-            "splitFactor": null
+            "show": true
           },
-          "yBucketBound": "auto",
-          "yBucketNumber": null,
-          "yBucketSize": null
+          "yBucketBound": "auto"
         },
         {
           "aliasColors": {},
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
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-              "custom": {},
               "links": []
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             "overrides": []
@@ -4175,7 +4337,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "8.4.3",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -4226,6 +4388,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.99, sum(rate(synapse_event_processing_lag_by_event_bucket{name='federation_sender',index=~\"$index\",instance=\"$instance\"}[$bucket_size])) by (le))",
               "format": "time_series",
               "interval": "",
@@ -4234,6 +4399,9 @@
               "refId": "D"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.9, sum(rate(synapse_event_processing_lag_by_event_bucket{name='federation_sender',index=~\"$index\",instance=\"$instance\"}[$bucket_size])) by (le))",
               "format": "time_series",
               "interval": "",
@@ -4242,6 +4410,9 @@
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.75, sum(rate(synapse_event_processing_lag_by_event_bucket{name='federation_sender',index=~\"$index\",instance=\"$instance\"}[$bucket_size])) by (le))",
               "format": "time_series",
               "interval": "",
@@ -4250,6 +4421,9 @@
               "refId": "C"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.5, sum(rate(synapse_event_processing_lag_by_event_bucket{name='federation_sender',index=~\"$index\",instance=\"$instance\"}[$bucket_size])) by (le))",
               "format": "time_series",
               "interval": "",
@@ -4258,18 +4432,27 @@
               "refId": "B"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.25, sum(rate(synapse_event_processing_lag_by_event_bucket{name='federation_sender',index=~\"$index\",instance=\"$instance\"}[$bucket_size])) by (le))",
               "interval": "",
               "legendFormat": "25%",
               "refId": "F"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.05, sum(rate(synapse_event_processing_lag_by_event_bucket{name='federation_sender',index=~\"$index\",instance=\"$instance\"}[$bucket_size])) by (le))",
               "interval": "",
               "legendFormat": "5%",
               "refId": "G"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_event_processing_lag_by_event_sum{name='federation_sender',index=~\"$index\",instance=\"$instance\"}[$bucket_size])) / sum(rate(synapse_event_processing_lag_by_event_count{name='federation_sender',index=~\"$index\",instance=\"$instance\"}[$bucket_size]))",
               "interval": "",
               "legendFormat": "Average",
@@ -4294,9 +4477,7 @@
               "yaxis": "left"
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-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Federation send PDU lag quantiles",
           "tooltip": {
             "shared": true,
@@ -4305,19 +4486,15 @@
           },
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-            "buckets": null,
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               "logBase": 1,
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@@ -4325,20 +4502,17 @@
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               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
           "cards": {
-            "cardPadding": -1,
-            "cardRound": null
+            "cardPadding": -1
           },
           "color": {
             "cardColor": "#b4ff00",
@@ -4349,12 +4523,8 @@
             "mode": "spectrum"
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           "dataFormat": "tsbuckets",
-          "datasource": "$datasource",
-          "fieldConfig": {
-            "defaults": {
-              "custom": {}
-            },
-            "overrides": []
+          "datasource": {
+            "uid": "$datasource"
           },
           "gridPos": {
             "h": 9,
@@ -4373,6 +4543,9 @@
           "reverseYBuckets": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_federation_server_pdu_process_time_bucket{instance=\"$instance\"}[$bucket_size])) by (le)",
               "format": "heatmap",
               "instant": false,
@@ -4392,32 +4565,26 @@
           "xAxis": {
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-          "xBucketNumber": null,
-          "xBucketSize": null,
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             "decimals": 0,
             "format": "s",
             "logBase": 1,
-            "max": null,
-            "min": null,
-            "show": true,
-            "splitFactor": null
+            "show": true
           },
-          "yBucketBound": "auto",
-          "yBucketNumber": null,
-          "yBucketSize": null
+          "yBucketBound": "auto"
         },
         {
           "aliasColors": {},
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "editable": true,
           "error": false,
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -4451,7 +4618,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "8.4.3",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -4461,6 +4628,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_federation_server_oldest_inbound_pdu_in_staging{job=\"$job\",index=~\"$index\",instance=\"$instance\"}",
               "format": "time_series",
               "interval": "",
@@ -4471,9 +4641,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Age of oldest event in staging area",
           "tooltip": {
             "msResolution": false,
@@ -4483,33 +4651,27 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
+              "$$hashKey": "object:92",
               "format": "ms",
-              "label": null,
               "logBase": 1,
-              "max": null,
               "min": 0,
               "show": true
             },
             {
+              "$$hashKey": "object:93",
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -4517,12 +4679,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "editable": true,
           "error": false,
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -4556,7 +4719,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "8.4.3",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -4566,6 +4729,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_federation_server_number_inbound_pdu_in_staging{job=\"$job\",index=~\"$index\",instance=\"$instance\"}",
               "format": "time_series",
               "interval": "",
@@ -4576,9 +4742,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Number of events in federation staging area",
           "tooltip": {
             "msResolution": false,
@@ -4588,33 +4752,27 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
+              "$$hashKey": "object:92",
               "format": "none",
-              "label": null,
               "logBase": 1,
-              "max": null,
               "min": 0,
               "show": true
             },
             {
+              "$$hashKey": "object:93",
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -4622,12 +4780,9 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "${DS_PROMETHEUS}",
-          "fieldConfig": {
-            "defaults": {
-              "custom": {}
-            },
-            "overrides": []
+          "datasource": {
+            "type": "prometheus",
+            "uid": "$datasource"
           },
           "fill": 1,
           "fillGradient": 0,
@@ -4655,7 +4810,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "8.4.3",
           "pointradius": 2,
           "points": false,
           "renderer": "flot",
@@ -4665,6 +4820,10 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_federation_soft_failed_events_total{instance=\"$instance\"}[$bucket_size]))",
               "interval": "",
               "legendFormat": "soft-failed events",
@@ -4672,9 +4831,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Soft-failed event rate",
           "tooltip": {
             "shared": true,
@@ -4683,42 +4840,47 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
+              "$$hashKey": "object:131",
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
+              "$$hashKey": "object:132",
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": false
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         }
       ],
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "$datasource"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Federation",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "$datasource"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
@@ -4732,10 +4894,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -4746,7 +4909,7 @@
             "h": 8,
             "w": 12,
             "x": 0,
-            "y": 34
+            "y": 32
           },
           "hiddenSeries": false,
           "id": 51,
@@ -4763,9 +4926,12 @@
           "linewidth": 1,
           "links": [],
           "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.1.3",
+          "pluginVersion": "8.4.3",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -4775,6 +4941,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_http_httppusher_http_pushes_processed{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]) and on (instance, job, index) (synapse_http_httppusher_http_pushes_failed + synapse_http_httppusher_http_pushes_processed) > 0",
               "format": "time_series",
               "interval": "",
@@ -4784,6 +4953,9 @@
               "step": 20
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_http_httppusher_http_pushes_failed{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]) and on (instance, job, index) (synapse_http_httppusher_http_pushes_failed + synapse_http_httppusher_http_pushes_processed) > 0",
               "format": "time_series",
               "intervalFactor": 2,
@@ -4793,9 +4965,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "HTTP Push rate",
           "tooltip": {
             "shared": true,
@@ -4804,33 +4974,24 @@
           },
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           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
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             "values": []
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-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
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         {
@@ -4838,11 +4999,12 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
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           "fieldConfig": {
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@@ -4853,7 +5015,7 @@
             "h": 8,
             "w": 12,
             "x": 12,
-            "y": 34
+            "y": 32
           },
           "hiddenSeries": false,
           "id": 134,
@@ -4870,8 +5032,11 @@
           "lines": true,
           "linewidth": 1,
           "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
           "percentage": false,
-          "pluginVersion": "7.1.3",
+          "pluginVersion": "8.4.3",
           "pointradius": 2,
           "points": false,
           "renderer": "flot",
@@ -4881,15 +5046,16 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "topk(10,synapse_pushers{job=~\"$job\",index=~\"$index\", instance=\"$instance\"})",
               "legendFormat": "{{kind}} {{app_id}}",
               "refId": "A"
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Active pusher instances by app",
           "tooltip": {
             "shared": false,
@@ -4898,60 +5064,65 @@
           },
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-            "buckets": null,
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-              "max": null,
-              "min": null,
               "show": true
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           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
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         }
       ],
-      "repeat": null,
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "$datasource"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Pushes",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "$datasource"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
         "x": 0,
         "y": 32
       },
-      "id": 58,
+      "id": 219,
       "panels": [
         {
           "aliasColors": {},
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "type": "prometheus",
+            "uid": "${DS_PROMETHEUS}"
+          },
+          "description": "How many entries in current state that we are iterating over while calculating push rules.",
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -4965,6 +5136,598 @@
             "y": 33
           },
           "hiddenSeries": false,
+          "id": 209,
+          "legend": {
+            "avg": false,
+            "current": false,
+            "max": false,
+            "min": false,
+            "show": false,
+            "total": false,
+            "values": false
+          },
+          "lines": true,
+          "linewidth": 1,
+          "links": [],
+          "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
+          "paceLength": 10,
+          "percentage": false,
+          "pluginVersion": "8.4.3",
+          "pointradius": 5,
+          "points": false,
+          "renderer": "flot",
+          "seriesOverrides": [],
+          "spaceLength": 10,
+          "stack": false,
+          "steppedLine": false,
+          "targets": [
+            {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
+              "exemplar": true,
+              "expr": "sum(rate(synapse_push_bulk_push_rule_evaluator_push_rules_state_size_counter{job=\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size]))",
+              "format": "time_series",
+              "interval": "",
+              "intervalFactor": 2,
+              "legendFormat": "{{index}}",
+              "metric": "synapse_push_bulk_push_rule_evaluator_push_rules_state_size_counter",
+              "refId": "A",
+              "step": 2
+            }
+          ],
+          "thresholds": [],
+          "timeRegions": [],
+          "title": "Iterations over State",
+          "tooltip": {
+            "shared": true,
+            "sort": 0,
+            "value_type": "individual"
+          },
+          "type": "graph",
+          "xaxis": {
+            "mode": "time",
+            "show": true,
+            "values": []
+          },
+          "yaxes": [
+            {
+              "format": "hertz",
+              "label": "",
+              "logBase": 1,
+              "min": "0",
+              "show": true
+            },
+            {
+              "format": "short",
+              "logBase": 1,
+              "show": true
+            }
+          ],
+          "yaxis": {
+            "align": false
+          }
+        },
+        {
+          "aliasColors": {},
+          "bars": false,
+          "dashLength": 10,
+          "dashes": false,
+          "datasource": {
+            "type": "prometheus",
+            "uid": "${DS_PROMETHEUS}"
+          },
+          "description": "Rate that the cached push rules for a room get invalidated due to underlying push rules being changed. ",
+          "fieldConfig": {
+            "defaults": {
+              "links": []
+            },
+            "overrides": []
+          },
+          "fill": 1,
+          "fillGradient": 0,
+          "gridPos": {
+            "h": 7,
+            "w": 12,
+            "x": 12,
+            "y": 33
+          },
+          "hiddenSeries": false,
+          "id": 211,
+          "legend": {
+            "avg": false,
+            "current": false,
+            "max": false,
+            "min": false,
+            "show": false,
+            "total": false,
+            "values": false
+          },
+          "lines": true,
+          "linewidth": 1,
+          "links": [],
+          "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
+          "paceLength": 10,
+          "percentage": false,
+          "pluginVersion": "8.4.3",
+          "pointradius": 5,
+          "points": false,
+          "renderer": "flot",
+          "seriesOverrides": [],
+          "spaceLength": 10,
+          "stack": false,
+          "steppedLine": false,
+          "targets": [
+            {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "$datasource"
+              },
+              "exemplar": true,
+              "expr": "sum(rate(synapse_push_bulk_push_rule_evaluator_push_rules_invalidation_counter{job=\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size]))",
+              "format": "time_series",
+              "interval": "",
+              "intervalFactor": 2,
+              "legendFormat": "{{index}}",
+              "metric": "synapse_push_bulk_push_rule_evaluator_push_rules_invalidation_counter",
+              "refId": "A",
+              "step": 2
+            }
+          ],
+          "thresholds": [],
+          "timeRegions": [],
+          "title": "Push Rule Invalidations",
+          "tooltip": {
+            "shared": true,
+            "sort": 0,
+            "value_type": "individual"
+          },
+          "type": "graph",
+          "xaxis": {
+            "mode": "time",
+            "show": true,
+            "values": []
+          },
+          "yaxes": [
+            {
+              "format": "hertz",
+              "label": "",
+              "logBase": 1,
+              "min": "0",
+              "show": true
+            },
+            {
+              "format": "short",
+              "logBase": 1,
+              "show": true
+            }
+          ],
+          "yaxis": {
+            "align": false
+          }
+        },
+        {
+          "aliasColors": {},
+          "bars": false,
+          "dashLength": 10,
+          "dashes": false,
+          "datasource": {
+            "type": "prometheus",
+            "uid": "${DS_PROMETHEUS}"
+          },
+          "description": "How often the \"delta optimisation\" happens.\n\nThe delta optimisation is when we update the push rules for a room incrementally after a state change where we know the delta between the old state and the new state.\n\nThis can't happen if we don't the delta or we're calculating push rules from scratch.",
+          "fieldConfig": {
+            "defaults": {
+              "links": []
+            },
+            "overrides": []
+          },
+          "fill": 1,
+          "fillGradient": 0,
+          "gridPos": {
+            "h": 7,
+            "w": 12,
+            "x": 0,
+            "y": 40
+          },
+          "hiddenSeries": false,
+          "id": 213,
+          "legend": {
+            "avg": false,
+            "current": false,
+            "max": false,
+            "min": false,
+            "show": true,
+            "total": false,
+            "values": false
+          },
+          "lines": true,
+          "linewidth": 1,
+          "links": [],
+          "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
+          "paceLength": 10,
+          "percentage": false,
+          "pluginVersion": "8.4.3",
+          "pointradius": 5,
+          "points": false,
+          "renderer": "flot",
+          "seriesOverrides": [
+            {
+              "alias": "Number of calls",
+              "yaxis": 2
+            }
+          ],
+          "spaceLength": 10,
+          "stack": false,
+          "steppedLine": false,
+          "targets": [
+            {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
+              "exemplar": true,
+              "expr": "sum(rate(synapse_util_caches_cache:hits{job=\"$job\",index=~\"$index\",name=\"push_rules_delta_state_cache_metric\",instance=\"$instance\"}[$bucket_size]))/sum(rate(synapse_util_caches_cache:total{job=\"$job\",index=~\"$index\", name=\"push_rules_delta_state_cache_metric\",instance=\"$instance\"}[$bucket_size]))",
+              "format": "time_series",
+              "interval": "",
+              "intervalFactor": 2,
+              "legendFormat": "Hit Rate",
+              "metric": "synapse_push_bulk_push_rule_evaluator_push_rules_invalidation_counter",
+              "refId": "A",
+              "step": 2
+            },
+            {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
+              "exemplar": true,
+              "expr": "sum(rate(synapse_util_caches_cache:total{job=\"$job\",index=~\"$index\", name=\"push_rules_delta_state_cache_metric\",instance=\"$instance\"}[$bucket_size]))",
+              "format": "time_series",
+              "interval": "",
+              "intervalFactor": 2,
+              "legendFormat": "Number of calls",
+              "refId": "B",
+              "step": 2
+            }
+          ],
+          "thresholds": [],
+          "timeRegions": [],
+          "title": "Delta Optimisation",
+          "tooltip": {
+            "shared": true,
+            "sort": 0,
+            "value_type": "individual"
+          },
+          "type": "graph",
+          "xaxis": {
+            "mode": "time",
+            "show": true,
+            "values": []
+          },
+          "yaxes": [
+            {
+              "format": "percentunit",
+              "label": "",
+              "logBase": 1,
+              "max": "1",
+              "min": "0",
+              "show": true
+            },
+            {
+              "format": "hertz",
+              "label": "",
+              "logBase": 1,
+              "min": "0",
+              "show": true
+            }
+          ],
+          "yaxis": {
+            "align": false
+          }
+        },
+        {
+          "aliasColors": {},
+          "bars": false,
+          "dashLength": 10,
+          "dashes": false,
+          "datasource": {
+            "type": "prometheus",
+            "uid": "${DS_PROMETHEUS}"
+          },
+          "description": "How often we have the correct cached push rules for a room.",
+          "fieldConfig": {
+            "defaults": {
+              "links": []
+            },
+            "overrides": []
+          },
+          "fill": 1,
+          "fillGradient": 0,
+          "gridPos": {
+            "h": 7,
+            "w": 12,
+            "x": 12,
+            "y": 40
+          },
+          "hiddenSeries": false,
+          "id": 215,
+          "legend": {
+            "avg": false,
+            "current": false,
+            "max": false,
+            "min": false,
+            "show": true,
+            "total": false,
+            "values": false
+          },
+          "lines": true,
+          "linewidth": 1,
+          "links": [],
+          "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
+          "paceLength": 10,
+          "percentage": false,
+          "pluginVersion": "8.4.3",
+          "pointradius": 5,
+          "points": false,
+          "renderer": "flot",
+          "seriesOverrides": [
+            {
+              "alias": "Number of calls",
+              "yaxis": 2
+            }
+          ],
+          "spaceLength": 10,
+          "stack": false,
+          "steppedLine": false,
+          "targets": [
+            {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
+              "exemplar": true,
+              "expr": "sum(rate(synapse_util_caches_cache:hits{job=\"$job\",index=~\"$index\",name=\"room_push_rule_cache\",instance=\"$instance\"}[$bucket_size]))/sum(rate(synapse_util_caches_cache:total{job=\"$job\",index=~\"$index\", name=\"room_push_rule_cache\",instance=\"$instance\"}[$bucket_size]))",
+              "format": "time_series",
+              "interval": "",
+              "intervalFactor": 2,
+              "legendFormat": "Hit Rate",
+              "metric": "synapse_push_bulk_push_rule_evaluator_push_rules_invalidation_counter",
+              "refId": "A",
+              "step": 2
+            },
+            {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
+              "exemplar": true,
+              "expr": "sum(rate(synapse_util_caches_cache:total{job=\"$job\",index=~\"$index\", name=\"room_push_rule_cache\",instance=\"$instance\"}[$bucket_size]))",
+              "format": "time_series",
+              "interval": "",
+              "intervalFactor": 2,
+              "legendFormat": "Number of calls",
+              "refId": "B",
+              "step": 2
+            }
+          ],
+          "thresholds": [],
+          "timeRegions": [],
+          "title": "How often we reuse existing calculated push rules",
+          "tooltip": {
+            "shared": true,
+            "sort": 0,
+            "value_type": "individual"
+          },
+          "type": "graph",
+          "xaxis": {
+            "mode": "time",
+            "show": true,
+            "values": []
+          },
+          "yaxes": [
+            {
+              "format": "percentunit",
+              "label": "",
+              "logBase": 1,
+              "max": "1",
+              "min": "0",
+              "show": true
+            },
+            {
+              "format": "hertz",
+              "logBase": 1,
+              "show": true
+            }
+          ],
+          "yaxis": {
+            "align": false
+          }
+        },
+        {
+          "aliasColors": {},
+          "bars": false,
+          "dashLength": 10,
+          "dashes": false,
+          "datasource": {
+            "type": "prometheus",
+            "uid": "${DS_PROMETHEUS}"
+          },
+          "description": "How often we have existing cached push rules for the room. \n\nNote that these might be outdated and need to be recalculated if the state has changed.",
+          "fieldConfig": {
+            "defaults": {
+              "links": []
+            },
+            "overrides": []
+          },
+          "fill": 1,
+          "fillGradient": 0,
+          "gridPos": {
+            "h": 7,
+            "w": 12,
+            "x": 0,
+            "y": 47
+          },
+          "hiddenSeries": false,
+          "id": 217,
+          "legend": {
+            "avg": false,
+            "current": false,
+            "max": false,
+            "min": false,
+            "show": true,
+            "total": false,
+            "values": false
+          },
+          "lines": true,
+          "linewidth": 1,
+          "links": [],
+          "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
+          "paceLength": 10,
+          "percentage": false,
+          "pluginVersion": "8.4.3",
+          "pointradius": 5,
+          "points": false,
+          "renderer": "flot",
+          "seriesOverrides": [
+            {
+              "alias": "Number of calls",
+              "yaxis": 2
+            }
+          ],
+          "spaceLength": 10,
+          "stack": false,
+          "steppedLine": false,
+          "targets": [
+            {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
+              "exemplar": true,
+              "expr": "sum(rate(synapse_util_caches_cache:hits{job=\"$job\",index=~\"$index\",name=\"_get_rules_for_room\",instance=\"$instance\"}[$bucket_size]))/sum(rate(synapse_util_caches_cache:total{job=\"$job\",index=~\"$index\", name=\"_get_rules_for_room\",instance=\"$instance\"}[$bucket_size]))",
+              "format": "time_series",
+              "interval": "",
+              "intervalFactor": 2,
+              "legendFormat": "Hit Rate",
+              "metric": "synapse_push_bulk_push_rule_evaluator_push_rules_invalidation_counter",
+              "refId": "A",
+              "step": 2
+            },
+            {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
+              "exemplar": true,
+              "expr": "sum(rate(synapse_util_caches_cache:total{job=\"$job\",index=~\"$index\", name=\"_get_rules_for_room\",instance=\"$instance\"}[$bucket_size]))",
+              "format": "time_series",
+              "interval": "",
+              "intervalFactor": 2,
+              "legendFormat": "Number of calls",
+              "refId": "B",
+              "step": 2
+            }
+          ],
+          "thresholds": [],
+          "timeRegions": [],
+          "title": "How often we have the RulesForRoom cached",
+          "tooltip": {
+            "shared": true,
+            "sort": 0,
+            "value_type": "individual"
+          },
+          "type": "graph",
+          "xaxis": {
+            "mode": "time",
+            "show": true,
+            "values": []
+          },
+          "yaxes": [
+            {
+              "format": "percentunit",
+              "label": "",
+              "logBase": 1,
+              "max": "1",
+              "min": "0",
+              "show": true
+            },
+            {
+              "format": "hertz",
+              "logBase": 1,
+              "show": true
+            }
+          ],
+          "yaxis": {
+            "align": false
+          }
+        }
+      ],
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "000000001"
+          },
+          "refId": "A"
+        }
+      ],
+      "title": "Push Rule Cache",
+      "type": "row"
+    },
+    {
+      "collapsed": true,
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
+      "gridPos": {
+        "h": 1,
+        "w": 24,
+        "x": 0,
+        "y": 33
+      },
+      "id": 58,
+      "panels": [
+        {
+          "aliasColors": {},
+          "bars": false,
+          "dashLength": 10,
+          "dashes": false,
+          "datasource": {
+            "uid": "$datasource"
+          },
+          "fieldConfig": {
+            "defaults": {
+              "links": []
+            },
+            "overrides": []
+          },
+          "fill": 1,
+          "fillGradient": 0,
+          "gridPos": {
+            "h": 7,
+            "w": 12,
+            "x": 0,
+            "y": 9
+          },
+          "hiddenSeries": false,
           "id": 48,
           "legend": {
             "avg": false,
@@ -4984,7 +5747,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -4994,6 +5757,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_storage_schedule_time_sum{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])/rate(synapse_storage_schedule_time_count[$bucket_size])",
               "format": "time_series",
               "intervalFactor": 2,
@@ -5003,9 +5769,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Avg time waiting for db conn",
           "tooltip": {
             "shared": true,
@@ -5014,34 +5778,26 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
-              "decimals": null,
               "format": "s",
               "label": "",
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": false
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -5049,11 +5805,12 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "description": "Shows the time in which the given percentage of database queries were scheduled, over the sampled timespan",
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -5064,7 +5821,7 @@
             "h": 7,
             "w": 12,
             "x": 12,
-            "y": 33
+            "y": 9
           },
           "hiddenSeries": false,
           "id": 104,
@@ -5087,7 +5844,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -5097,6 +5854,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.99, rate(synapse_storage_schedule_time_bucket{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]))",
               "format": "time_series",
               "hide": false,
@@ -5106,6 +5866,9 @@
               "step": 20
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.95, rate(synapse_storage_schedule_time_bucket{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -5113,6 +5876,9 @@
               "refId": "B"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.90, rate(synapse_storage_schedule_time_bucket{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -5120,6 +5886,9 @@
               "refId": "C"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_storage_schedule_time_sum{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])/rate(synapse_storage_schedule_time_count{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "interval": "",
@@ -5129,9 +5898,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Db scheduling time quantiles",
           "tooltip": {
             "shared": false,
@@ -5140,34 +5907,26 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
-              "decimals": null,
               "format": "s",
               "label": "",
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             },
             {
               "format": "short",
-              "label": null,
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-              "max": null,
-              "min": null,
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           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
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         {
@@ -5175,12 +5934,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
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           "error": false,
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               "links": []
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@@ -5192,7 +5952,7 @@
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+            "y": 16
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@@ -5216,7 +5976,7 @@
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           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -5226,6 +5986,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "topk(10, rate(synapse_storage_transaction_time_count{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]))",
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@@ -5236,9 +5999,7 @@
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@@ -5247,9 +6008,7 @@
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@@ -5257,21 +6016,17 @@
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-              "min": null,
               "show": true
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           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
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         {
@@ -5279,12 +6034,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
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           "error": false,
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               "links": []
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@@ -5296,7 +6052,7 @@
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+            "y": 16
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@@ -5320,7 +6076,7 @@
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           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -5330,6 +6086,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_storage_transaction_time_sum{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "instant": false,
@@ -5341,9 +6100,7 @@
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-          "timeFrom": null,
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-          "timeShift": null,
           "title": "DB transactions by total txn time",
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@@ -5352,9 +6109,7 @@
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-            "buckets": null,
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@@ -5362,21 +6117,16 @@
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-              "max": null,
-              "min": null,
               "show": true
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           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
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         {
@@ -5384,12 +6134,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
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           "error": false,
           "fieldConfig": {
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               "links": []
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@@ -5401,7 +6152,7 @@
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+            "y": 23
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@@ -5425,7 +6176,7 @@
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           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -5435,6 +6186,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_storage_transaction_time_sum{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])/rate(synapse_storage_transaction_time_count{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
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@@ -5446,9 +6200,7 @@
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           "title": "Average DB txn time",
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@@ -5457,9 +6209,7 @@
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@@ -5467,21 +6217,16 @@
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-              "min": null,
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           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
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@@ -5489,10 +6234,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
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@@ -5503,7 +6249,7 @@
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-            "y": 47
+            "y": 23
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@@ -5524,7 +6270,7 @@
             "alertThreshold": true
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-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -5534,6 +6280,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.99, sum(rate(synapse_storage_schedule_time_bucket{index=~\"$index\",instance=\"$instance\",job=\"$job\"}[$bucket_size])) by (le))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -5541,6 +6290,9 @@
               "refId": "D"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.9, sum(rate(synapse_storage_schedule_time_bucket{index=~\"$index\",instance=\"$instance\",job=\"$job\"}[$bucket_size])) by (le))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -5548,6 +6300,9 @@
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.75, sum(rate(synapse_storage_schedule_time_bucket{index=~\"$index\",instance=\"$instance\",job=\"$job\"}[$bucket_size])) by (le))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -5555,6 +6310,9 @@
               "refId": "C"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.5, sum(rate(synapse_storage_schedule_time_bucket{index=~\"$index\",instance=\"$instance\",job=\"$job\"}[$bucket_size])) by (le))",
               "format": "time_series",
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@@ -5563,9 +6321,7 @@
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-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Time waiting for DB connection quantiles",
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@@ -5574,49 +6330,54 @@
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             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
-              "decimals": null,
+              "$$hashKey": "object:203",
               "format": "s",
               "label": "",
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             },
             {
+              "$$hashKey": "object:204",
               "format": "short",
-              "label": null,
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-              "max": null,
-              "min": null,
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           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
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       ],
-      "repeat": null,
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "000000001"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Database",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "gridPos": {
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         "w": 24,
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       "panels": [
@@ -5625,12 +6386,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
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@@ -5642,7 +6404,7 @@
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           },
           "hiddenSeries": false,
           "id": 12,
@@ -5660,9 +6422,12 @@
           "linewidth": 2,
           "links": [],
           "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
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           "percentage": false,
-          "pluginVersion": "7.1.3",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -5672,6 +6437,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_util_metrics_block_ru_utime_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\",block_name!=\"wrapped_request_handler\"}[$bucket_size]) + rate(synapse_util_metrics_block_ru_stime_seconds[$bucket_size])",
               "format": "time_series",
               "interval": "",
@@ -5682,9 +6450,7 @@
             }
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-          "timeShift": null,
           "title": "Total CPU Usage by Block",
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@@ -5693,9 +6459,7 @@
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@@ -5703,21 +6467,16 @@
             {
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-              "min": null,
               "show": true
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           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
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         {
@@ -5725,12 +6484,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
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           "error": false,
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@@ -5742,7 +6502,7 @@
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           "hiddenSeries": false,
           "id": 26,
@@ -5760,9 +6520,12 @@
           "linewidth": 2,
           "links": [],
           "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
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           "percentage": false,
-          "pluginVersion": "7.1.3",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -5772,6 +6535,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "(rate(synapse_util_metrics_block_ru_utime_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]) + rate(synapse_util_metrics_block_ru_stime_seconds[$bucket_size])) / rate(synapse_util_metrics_block_count[$bucket_size])",
               "format": "time_series",
               "interval": "",
@@ -5782,9 +6548,7 @@
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-          "timeShift": null,
           "title": "Average CPU Time per Block",
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@@ -5793,9 +6557,7 @@
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@@ -5803,21 +6565,16 @@
             {
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-              "min": null,
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-            "align": false,
-            "alignLevel": null
+            "align": false
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@@ -5825,12 +6582,14 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "type": "prometheus",
+            "uid": "${DS_PROMETHEUS}"
+          },
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           "error": false,
           "fieldConfig": {
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@@ -5842,7 +6601,7 @@
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+            "y": 23
           },
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           "id": 13,
@@ -5860,9 +6619,12 @@
           "linewidth": 2,
           "links": [],
           "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
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           "percentage": false,
-          "pluginVersion": "7.1.3",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -5872,19 +6634,22 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
+              "exemplar": true,
               "expr": "rate(synapse_util_metrics_block_db_txn_duration_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "interval": "",
               "intervalFactor": 2,
-              "legendFormat": "{{job}} {{block_name}}",
+              "legendFormat": "{{job}}-{{index}} {{block_name}}",
               "refId": "A",
               "step": 20
             }
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           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
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           "title": "Total DB Usage by Block",
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@@ -5893,31 +6658,27 @@
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-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
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           "yaxes": [
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+              "$$hashKey": "object:196",
               "format": "percentunit",
               "logBase": 1,
-              "max": null,
               "min": 0,
               "show": true
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+              "$$hashKey": "object:197",
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-              "min": null,
               "show": true
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           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
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         {
@@ -5925,13 +6686,14 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "description": "The time each database transaction takes to execute, on average, broken down by metrics block.",
           "editable": true,
           "error": false,
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@@ -5943,7 +6705,7 @@
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+            "y": 23
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           "id": 27,
@@ -5961,9 +6723,12 @@
           "linewidth": 2,
           "links": [],
           "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
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           "percentage": false,
-          "pluginVersion": "7.1.3",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -5973,6 +6738,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_util_metrics_block_db_txn_duration_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]) / rate(synapse_util_metrics_block_db_txn_count{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
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@@ -5983,9 +6751,7 @@
             }
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           "title": "Average Database Transaction time, by Block",
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@@ -5994,9 +6760,7 @@
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@@ -6004,21 +6768,16 @@
             {
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               "format": "short",
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-              "max": null,
-              "min": null,
               "show": true
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           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
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         {
@@ -6026,12 +6785,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
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           "error": false,
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@@ -6043,7 +6803,7 @@
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+            "y": 36
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           "id": 28,
@@ -6060,9 +6820,12 @@
           "linewidth": 2,
           "links": [],
           "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
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           "percentage": false,
-          "pluginVersion": "7.1.3",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -6072,6 +6835,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_util_metrics_block_db_txn_duration_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]) / rate(synapse_util_metrics_block_db_txn_count{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
               "interval": "",
@@ -6082,9 +6848,7 @@
             }
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           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Average Transactions per Block",
           "tooltip": {
             "shared": false,
@@ -6093,9 +6857,7 @@
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@@ -6103,21 +6865,16 @@
             {
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-              "min": null,
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-            "align": false,
-            "alignLevel": null
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@@ -6125,12 +6882,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
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@@ -6142,7 +6900,7 @@
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           },
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           "id": 25,
@@ -6159,9 +6917,12 @@
           "linewidth": 2,
           "links": [],
           "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
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           "percentage": false,
-          "pluginVersion": "7.1.3",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -6171,6 +6932,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_util_metrics_block_time_seconds{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]) / rate(synapse_util_metrics_block_count[$bucket_size])",
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@@ -6181,9 +6945,7 @@
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@@ -6192,9 +6954,7 @@
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@@ -6202,21 +6962,16 @@
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-              "min": null,
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-            "align": false,
-            "alignLevel": null
+            "align": false
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@@ -6224,12 +6979,8 @@
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           "dashes": false,
-          "datasource": "$datasource",
-          "fieldConfig": {
-            "defaults": {
-              "custom": {}
-            },
-            "overrides": []
+          "datasource": {
+            "uid": "$datasource"
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           "fillGradient": 0,
@@ -6237,7 +6988,7 @@
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             "w": 12,
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           },
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           "id": 154,
@@ -6254,8 +7005,11 @@
           "lines": true,
           "linewidth": 1,
           "nullPointMode": "null",
+          "options": {
+            "alertThreshold": true
+          },
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-          "pluginVersion": "7.1.3",
+          "pluginVersion": "8.4.3",
           "pointradius": 2,
           "points": false,
           "renderer": "flot",
@@ -6265,6 +7019,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_util_metrics_block_count{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "interval": "",
               "legendFormat": "{{job}}-{{index}} {{block_name}}",
@@ -6272,9 +7029,7 @@
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@@ -6283,48 +7038,50 @@
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-              "min": null,
               "show": true
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           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
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-      "repeat": null,
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "000000001"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Per-block metrics",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "gridPos": {
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         "w": 24,
         "x": 0,
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       "panels": [
@@ -6333,13 +7090,14 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
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           "error": false,
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@@ -6351,7 +7109,7 @@
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@@ -6375,7 +7133,7 @@
             "alertThreshold": true
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-          "pluginVersion": "7.3.7",
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           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -6385,6 +7143,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_util_caches_cache:hits{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])/rate(synapse_util_caches_cache:total{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
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@@ -6394,9 +7155,7 @@
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@@ -6406,15 +7165,12 @@
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@@ -6425,14 +7181,11 @@
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-              "max": null,
-              "min": null,
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-            "align": false,
-            "alignLevel": null
+            "align": false
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@@ -6440,12 +7193,13 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
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@@ -6457,7 +7211,7 @@
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@@ -6480,7 +7234,7 @@
             "alertThreshold": true
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           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -6490,6 +7244,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_util_caches_cache:size{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
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@@ -6501,9 +7258,7 @@
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@@ -6512,9 +7267,7 @@
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@@ -6522,21 +7275,17 @@
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-              "min": null,
               "show": true
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-            "alignLevel": null
+            "align": false
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@@ -6544,12 +7293,13 @@
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           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
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@@ -6561,7 +7311,7 @@
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@@ -6584,7 +7334,7 @@
             "alertThreshold": true
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-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -6594,6 +7344,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_util_caches_cache:total{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
               "format": "time_series",
               "interval": "",
@@ -6604,9 +7357,7 @@
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@@ -6615,9 +7366,7 @@
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@@ -6625,21 +7374,17 @@
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@@ -6647,10 +7392,11 @@
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           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
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@@ -6661,7 +7407,7 @@
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@@ -6683,7 +7429,7 @@
             "alertThreshold": true
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-          "pluginVersion": "7.3.7",
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           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -6693,6 +7439,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "topk(10, rate(synapse_util_caches_cache:total{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size]) - rate(synapse_util_caches_cache:hits{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size]))",
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@@ -6703,9 +7452,7 @@
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@@ -6714,33 +7461,24 @@
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-            "alignLevel": null
+            "align": false
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@@ -6748,10 +7486,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
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@@ -6762,7 +7501,7 @@
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@@ -6784,7 +7523,7 @@
             "alertThreshold": true
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-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -6794,17 +7533,19 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_util_caches_cache:evicted_size{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "time_series",
+              "interval": "",
               "intervalFactor": 1,
               "legendFormat": "{{name}} ({{reason}}) {{job}}-{{index}}",
               "refId": "A"
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-          "timeFrom": null,
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@@ -6813,49 +7554,51 @@
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-              "min": null,
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-            "align": false,
-            "alignLevel": null
+            "align": false
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       ],
-      "repeat": null,
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "000000001"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Caches",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "gridPos": {
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         "w": 24,
         "x": 0,
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       "panels": [
@@ -6864,7 +7607,9 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
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@@ -6908,6 +7653,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_util_caches_response_cache:size{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
               "interval": "",
               "legendFormat": "{{name}} {{job}}-{{index}}",
@@ -6915,9 +7663,7 @@
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@@ -6926,33 +7672,24 @@
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-              "min": null,
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-            "alignLevel": null
+            "align": false
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@@ -6960,7 +7697,9 @@
           "bars": false,
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           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
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             "defaults": {
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@@ -7004,12 +7743,18 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_util_caches_response_cache:hits{instance=\"$instance\", job=~\"$job\", index=~\"$index\"}[$bucket_size])/rate(synapse_util_caches_response_cache:total{instance=\"$instance\", job=~\"$job\", index=~\"$index\"}[$bucket_size])",
               "interval": "",
               "legendFormat": "{{name}} {{job}}-{{index}}",
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "",
               "interval": "",
               "legendFormat": "",
@@ -7017,9 +7762,7 @@
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@@ -7028,17 +7771,13 @@
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@@ -7046,30 +7785,38 @@
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-              "min": null,
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           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
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+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "000000001"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Response caches",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
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         "w": 24,
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+        "y": 37
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       "panels": [
@@ -7078,7 +7825,9 @@
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           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
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             "defaults": {
               "custom": {},
@@ -7123,6 +7872,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(python_gc_time_sum{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[10m])",
               "format": "time_series",
               "instant": false,
@@ -7132,9 +7884,7 @@
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           "title": "Total GC time by bucket (10m smoothing)",
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@@ -7143,34 +7893,25 @@
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@@ -7178,7 +7919,9 @@
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           "editable": true,
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@@ -7228,6 +7971,9 @@
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@@ -7238,9 +7984,7 @@
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@@ -7249,9 +7993,7 @@
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@@ -7334,6 +8073,9 @@
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@@ -7342,9 +8084,7 @@
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@@ -7353,9 +8093,7 @@
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@@ -7364,23 +8102,17 @@
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@@ -7433,6 +8167,9 @@
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@@ -7441,9 +8178,7 @@
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@@ -7452,33 +8187,24 @@
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@@ -7486,7 +8212,9 @@
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@@ -7531,6 +8259,9 @@
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@@ -7539,9 +8270,7 @@
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@@ -7550,51 +8279,43 @@
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@@ -7618,6 +8339,10 @@
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+                "uid": "${DS_PROMETHEUS}"
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@@ -7634,34 +8359,37 @@
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@@ -7670,10 +8398,11 @@
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@@ -7684,10 +8413,10 @@
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@@ -7706,7 +8435,7 @@
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@@ -7716,7 +8445,10 @@
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@@ -7725,10 +8457,8 @@
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@@ -7736,241 +8466,326 @@
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           "aliasColors": {},
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "type": "prometheus",
+            "uid": "${DS_PROMETHEUS}"
+          },
+          "description": "",
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -7980,11 +8795,11 @@
           "gridPos": {
             "h": 7,
             "w": 12,
-            "x": 12,
-            "y": 20
+            "x": 0,
+            "y": 28
           },
           "hiddenSeries": false,
-          "id": 41,
+          "id": 144,
           "legend": {
             "avg": false,
             "current": false,
@@ -7996,15 +8811,13 @@
           },
           "lines": true,
           "linewidth": 1,
-          "links": [],
           "nullPointMode": "null",
           "options": {
             "alertThreshold": true
           },
-          "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
-          "pointradius": 5,
+          "pluginVersion": "8.4.3",
+          "pointradius": 2,
           "points": false,
           "renderer": "flot",
           "seriesOverrides": [],
@@ -8013,20 +8826,19 @@
           "steppedLine": false,
           "targets": [
             {
-              "expr": "rate(synapse_replication_tcp_resource_stream_updates{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
-              "format": "time_series",
+              "datasource": {
+                "type": "prometheus",
+                "uid": "${DS_PROMETHEUS}"
+              },
+              "expr": "synapse_replication_tcp_command_queue{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
               "interval": "",
-              "intervalFactor": 2,
-              "legendFormat": "{{stream_name}}",
-              "refId": "A",
-              "step": 20
+              "legendFormat": "{{stream_name}} {{job}}-{{index}}",
+              "refId": "A"
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
-          "title": "Outgoing stream updates",
+          "title": "Queued incoming RDATA commands, by stream",
           "tooltip": {
             "shared": false,
             "sort": 0,
@@ -8034,33 +8846,26 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
-              "format": "hertz",
-              "label": null,
+              "$$hashKey": "object:218",
+              "format": "short",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
+              "$$hashKey": "object:219",
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -8068,10 +8873,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -8081,11 +8887,11 @@
           "gridPos": {
             "h": 7,
             "w": 12,
-            "x": 0,
-            "y": 27
+            "x": 12,
+            "y": 28
           },
           "hiddenSeries": false,
-          "id": 113,
+          "id": 115,
           "legend": {
             "avg": false,
             "current": false,
@@ -8104,7 +8910,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "8.4.3",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -8114,25 +8920,19 @@
           "steppedLine": false,
           "targets": [
             {
-              "expr": "synapse_replication_tcp_resource_connections_per_stream{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}",
+              "datasource": {
+                "uid": "$datasource"
+              },
+              "expr": "rate(synapse_replication_tcp_protocol_close_reason{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
               "format": "time_series",
               "intervalFactor": 1,
-              "legendFormat": "{{job}}-{{index}} {{stream_name}}",
+              "legendFormat": "{{job}}-{{index}} {{reason_type}}",
               "refId": "A"
-            },
-            {
-              "expr": "synapse_replication_tcp_resource_total_connections{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}",
-              "format": "time_series",
-              "intervalFactor": 1,
-              "legendFormat": "{{job}}-{{index}}",
-              "refId": "B"
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
-          "title": "Replication connections",
+          "title": "Replication connection close reasons",
           "tooltip": {
             "shared": true,
             "sort": 0,
@@ -8140,33 +8940,24 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
-              "format": "short",
-              "label": null,
+              "format": "hertz",
               "logBase": 1,
-              "max": null,
-              "min": "0",
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -8174,10 +8965,11 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {},
               "links": []
             },
             "overrides": []
@@ -8187,11 +8979,11 @@
           "gridPos": {
             "h": 7,
             "w": 12,
-            "x": 12,
-            "y": 27
+            "x": 0,
+            "y": 35
           },
           "hiddenSeries": false,
-          "id": 115,
+          "id": 113,
           "legend": {
             "avg": false,
             "current": false,
@@ -8210,7 +9002,7 @@
           },
           "paceLength": 10,
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "8.4.3",
           "pointradius": 5,
           "points": false,
           "renderer": "flot",
@@ -8220,18 +9012,29 @@
           "steppedLine": false,
           "targets": [
             {
-              "expr": "rate(synapse_replication_tcp_protocol_close_reason{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
+              "datasource": {
+                "uid": "$datasource"
+              },
+              "expr": "synapse_replication_tcp_resource_connections_per_stream{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}",
               "format": "time_series",
               "intervalFactor": 1,
-              "legendFormat": "{{job}}-{{index}} {{reason_type}}",
+              "legendFormat": "{{job}}-{{index}} {{stream_name}}",
               "refId": "A"
+            },
+            {
+              "datasource": {
+                "uid": "$datasource"
+              },
+              "expr": "synapse_replication_tcp_resource_total_connections{job=~\"$job\",index=~\"$index\",instance=\"$instance\"}",
+              "format": "time_series",
+              "intervalFactor": 1,
+              "legendFormat": "{{job}}-{{index}}",
+              "refId": "B"
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
-          "title": "Replication connection close reasons",
+          "title": "Replication connections",
           "tooltip": {
             "shared": true,
             "sort": 0,
@@ -8239,48 +9042,51 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
-              "format": "hertz",
-              "label": null,
+              "format": "short",
               "logBase": 1,
-              "max": null,
-              "min": null,
+              "min": "0",
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         }
       ],
-      "repeat": null,
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "000000001"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Replication",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
         "x": 0,
-        "y": 38
+        "y": 39
       },
       "id": 69,
       "panels": [
@@ -8289,7 +9095,9 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
               "custom": {},
@@ -8335,6 +9143,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "max(synapse_event_persisted_position{instance=\"$instance\"}) - on() group_right() synapse_event_processing_positions{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
               "format": "time_series",
               "interval": "",
@@ -8344,9 +9155,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Event processing lag",
           "tooltip": {
             "shared": true,
@@ -8355,9 +9164,7 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
@@ -8366,22 +9173,17 @@
               "format": "short",
               "label": "events",
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -8389,7 +9191,9 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
               "custom": {},
@@ -8435,6 +9239,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "time()*1000-synapse_event_processing_last_ts{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}",
               "format": "time_series",
               "hide": false,
@@ -8445,9 +9252,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Age of last processed event",
           "tooltip": {
             "shared": true,
@@ -8456,33 +9261,25 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "ms",
-              "label": null,
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -8490,7 +9287,9 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
               "custom": {},
@@ -8537,6 +9336,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "deriv(synapse_event_processing_last_ts{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])/1000 - 1",
               "format": "time_series",
               "hide": false,
@@ -8547,9 +9349,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Event processing catchup rate",
           "tooltip": {
             "shared": true,
@@ -8558,67 +9358,70 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
-              "decimals": null,
               "format": "none",
               "label": "fallbehind(-) / catchup(+):  s/sec",
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         }
       ],
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "000000001"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Event processing loop positions",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
         "x": 0,
-        "y": 39
+        "y": 40
       },
       "id": 126,
       "panels": [
         {
           "cards": {
-            "cardPadding": 0,
-            "cardRound": null
+            "cardPadding": 0
           },
           "color": {
             "cardColor": "#B877D9",
             "colorScale": "sqrt",
             "colorScheme": "interpolateInferno",
             "exponent": 0.5,
-            "max": null,
             "min": 0,
             "mode": "opacity"
           },
           "dataFormat": "tsbuckets",
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "description": "Colour reflects the number of rooms with the given number of forward extremities, or fewer.\n\nThis is only updated once an hour.",
           "fieldConfig": {
             "defaults": {
@@ -8643,6 +9446,9 @@
           "reverseYBuckets": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_forward_extremities_bucket{instance=\"$instance\"} and on (index, instance, job) (synapse_storage_events_persisted_events > 0)",
               "format": "heatmap",
               "intervalFactor": 1,
@@ -8650,8 +9456,6 @@
               "refId": "A"
             }
           ],
-          "timeFrom": null,
-          "timeShift": null,
           "title": "Number of rooms, by number of forward extremities in room",
           "tooltip": {
             "show": true,
@@ -8661,27 +9465,22 @@
           "xAxis": {
             "show": true
           },
-          "xBucketNumber": null,
-          "xBucketSize": null,
           "yAxis": {
             "decimals": 0,
             "format": "short",
             "logBase": 1,
-            "max": null,
-            "min": null,
-            "show": true,
-            "splitFactor": null
+            "show": true
           },
-          "yBucketBound": "auto",
-          "yBucketNumber": null,
-          "yBucketSize": null
+          "yBucketBound": "auto"
         },
         {
           "aliasColors": {},
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "description": "Number of rooms with the given number of forward extremities or fewer.\n\nThis is only updated once an hour.",
           "fieldConfig": {
             "defaults": {
@@ -8725,6 +9524,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_forward_extremities_bucket{instance=\"$instance\"} > 0",
               "format": "heatmap",
               "interval": "",
@@ -8734,9 +9536,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Room counts, by number of extremities",
           "tooltip": {
             "shared": true,
@@ -8745,40 +9545,30 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
-              "decimals": null,
               "format": "none",
               "label": "Number of rooms",
               "logBase": 10,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": false
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
           "cards": {
-            "cardPadding": 0,
-            "cardRound": null
+            "cardPadding": 0
           },
           "color": {
             "cardColor": "#5794F2",
@@ -8789,7 +9579,9 @@
             "mode": "opacity"
           },
           "dataFormat": "tsbuckets",
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "description": "Colour reflects the number of events persisted to rooms with the given number of forward extremities, or fewer.",
           "fieldConfig": {
             "defaults": {
@@ -8814,6 +9606,9 @@
           "reverseYBuckets": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_storage_events_forward_extremities_persisted_bucket{instance=\"$instance\"}[$bucket_size]) and on (index, instance, job) (synapse_storage_events_persisted_events > 0)",
               "format": "heatmap",
               "intervalFactor": 1,
@@ -8821,8 +9616,6 @@
               "refId": "A"
             }
           ],
-          "timeFrom": null,
-          "timeShift": null,
           "title": "Events persisted, by number of forward extremities in room (heatmap)",
           "tooltip": {
             "show": true,
@@ -8832,27 +9625,22 @@
           "xAxis": {
             "show": true
           },
-          "xBucketNumber": null,
-          "xBucketSize": null,
           "yAxis": {
             "decimals": 0,
             "format": "short",
             "logBase": 1,
-            "max": null,
-            "min": null,
-            "show": true,
-            "splitFactor": null
+            "show": true
           },
-          "yBucketBound": "auto",
-          "yBucketNumber": null,
-          "yBucketSize": null
+          "yBucketBound": "auto"
         },
         {
           "aliasColors": {},
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "description": "For a given percentage P, the number X where P% of events were persisted to rooms with X forward extremities or fewer.",
           "fieldConfig": {
             "defaults": {
@@ -8895,6 +9683,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.5, rate(synapse_storage_events_forward_extremities_persisted_bucket{instance=\"$instance\"}[$bucket_size]) and on (index, instance, job) (synapse_storage_events_persisted_events > 0))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -8902,6 +9693,9 @@
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.75, rate(synapse_storage_events_forward_extremities_persisted_bucket{instance=\"$instance\"}[$bucket_size]) and on (index, instance, job) (synapse_storage_events_persisted_events > 0))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -8909,6 +9703,9 @@
               "refId": "B"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.90, rate(synapse_storage_events_forward_extremities_persisted_bucket{instance=\"$instance\"}[$bucket_size]) and on (index, instance, job) (synapse_storage_events_persisted_events > 0))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -8916,6 +9713,9 @@
               "refId": "C"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.99, rate(synapse_storage_events_forward_extremities_persisted_bucket{instance=\"$instance\"}[$bucket_size]) and on (index, instance, job) (synapse_storage_events_persisted_events > 0))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -8924,9 +9724,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Events persisted, by number of forward extremities in room (quantiles)",
           "tooltip": {
             "shared": true,
@@ -8935,9 +9733,7 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
@@ -8946,28 +9742,22 @@
               "format": "short",
               "label": "Number of extremities in room",
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
           "cards": {
-            "cardPadding": 0,
-            "cardRound": null
+            "cardPadding": 0
           },
           "color": {
             "cardColor": "#FF9830",
@@ -8978,7 +9768,9 @@
             "mode": "opacity"
           },
           "dataFormat": "tsbuckets",
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "description": "Colour reflects the number of events persisted to rooms with the given number of stale forward extremities, or fewer.\n\nStale forward extremities are those that were in the previous set of extremities as well as the new.",
           "fieldConfig": {
             "defaults": {
@@ -9003,6 +9795,9 @@
           "reverseYBuckets": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_storage_events_stale_forward_extremities_persisted_bucket{instance=\"$instance\"}[$bucket_size]) and on (index, instance, job) (synapse_storage_events_persisted_events > 0)",
               "format": "heatmap",
               "intervalFactor": 1,
@@ -9010,8 +9805,6 @@
               "refId": "A"
             }
           ],
-          "timeFrom": null,
-          "timeShift": null,
           "title": "Events persisted, by number of stale forward extremities in room (heatmap)",
           "tooltip": {
             "show": true,
@@ -9021,27 +9814,22 @@
           "xAxis": {
             "show": true
           },
-          "xBucketNumber": null,
-          "xBucketSize": null,
           "yAxis": {
             "decimals": 0,
             "format": "short",
             "logBase": 1,
-            "max": null,
-            "min": null,
-            "show": true,
-            "splitFactor": null
+            "show": true
           },
-          "yBucketBound": "auto",
-          "yBucketNumber": null,
-          "yBucketSize": null
+          "yBucketBound": "auto"
         },
         {
           "aliasColors": {},
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "description": "For  given percentage P, the number X where P% of events were persisted to rooms with X stale forward extremities or fewer.\n\nStale forward extremities are those that were in the previous set of extremities as well as the new.",
           "fieldConfig": {
             "defaults": {
@@ -9084,6 +9872,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.5, rate(synapse_storage_events_stale_forward_extremities_persisted_bucket{instance=\"$instance\"}[$bucket_size]) and on (index, instance, job) (synapse_storage_events_persisted_events > 0))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -9091,6 +9882,9 @@
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.75, rate(synapse_storage_events_stale_forward_extremities_persisted_bucket{instance=\"$instance\"}[$bucket_size]) and on (index, instance, job) (synapse_storage_events_persisted_events > 0))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -9098,6 +9892,9 @@
               "refId": "B"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.90, rate(synapse_storage_events_stale_forward_extremities_persisted_bucket{instance=\"$instance\"}[$bucket_size]) and on (index, instance, job) (synapse_storage_events_persisted_events > 0))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -9105,6 +9902,9 @@
               "refId": "C"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.99, rate(synapse_storage_events_stale_forward_extremities_persisted_bucket{instance=\"$instance\"}[$bucket_size]) and on (index, instance, job) (synapse_storage_events_persisted_events > 0))",
               "format": "time_series",
               "intervalFactor": 1,
@@ -9113,9 +9913,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Events persisted, by number of stale forward extremities in room (quantiles)",
           "tooltip": {
             "shared": true,
@@ -9124,9 +9922,7 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
@@ -9135,28 +9931,22 @@
               "format": "short",
               "label": "Number of stale forward extremities in room",
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
           "cards": {
-            "cardPadding": 0,
-            "cardRound": null
+            "cardPadding": 0
           },
           "color": {
             "cardColor": "#73BF69",
@@ -9167,7 +9957,9 @@
             "mode": "opacity"
           },
           "dataFormat": "tsbuckets",
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "description": "Colour reflects the number of state resolution operations performed over the given number of state groups, or fewer.",
           "fieldConfig": {
             "defaults": {
@@ -9192,6 +9984,9 @@
           "reverseYBuckets": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_state_number_state_groups_in_resolution_bucket{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size])",
               "format": "heatmap",
               "interval": "",
@@ -9200,8 +9995,6 @@
               "refId": "A"
             }
           ],
-          "timeFrom": null,
-          "timeShift": null,
           "title": "Number of state resolution performed, by number of state groups involved (heatmap)",
           "tooltip": {
             "show": true,
@@ -9211,27 +10004,22 @@
           "xAxis": {
             "show": true
           },
-          "xBucketNumber": null,
-          "xBucketSize": null,
           "yAxis": {
             "decimals": 0,
             "format": "short",
             "logBase": 1,
-            "max": null,
-            "min": null,
-            "show": true,
-            "splitFactor": null
+            "show": true
           },
-          "yBucketBound": "auto",
-          "yBucketNumber": null,
-          "yBucketSize": null
+          "yBucketBound": "auto"
         },
         {
           "aliasColors": {},
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "description": "For a given percentage P, the number X where P% of state resolution operations took place over X state groups or fewer.",
           "fieldConfig": {
             "defaults": {
@@ -9275,6 +10063,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.5, rate(synapse_state_number_state_groups_in_resolution_bucket{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]))",
               "format": "time_series",
               "interval": "",
@@ -9283,6 +10074,9 @@
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.75, rate(synapse_state_number_state_groups_in_resolution_bucket{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]))",
               "format": "time_series",
               "interval": "",
@@ -9291,6 +10085,9 @@
               "refId": "B"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.90, rate(synapse_state_number_state_groups_in_resolution_bucket{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]))",
               "format": "time_series",
               "interval": "",
@@ -9299,6 +10096,9 @@
               "refId": "C"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "histogram_quantile(0.99, rate(synapse_state_number_state_groups_in_resolution_bucket{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]))",
               "format": "time_series",
               "interval": "",
@@ -9308,9 +10108,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Number of state resolutions performed, by number of state groups involved (quantiles)",
           "tooltip": {
             "shared": true,
@@ -9319,9 +10117,7 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
@@ -9330,22 +10126,17 @@
               "format": "short",
               "label": "Number of state groups",
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -9353,7 +10144,9 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "description": "When we do a state res while persisting events we try and see if we can prune any stale extremities.",
           "fieldConfig": {
             "defaults": {
@@ -9394,18 +10187,27 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_storage_events_state_resolutions_during_persistence{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]))",
               "interval": "",
               "legendFormat": "State res ",
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_storage_events_potential_times_prune_extremities{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]))",
               "interval": "",
               "legendFormat": "Potential to prune",
               "refId": "B"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "sum(rate(synapse_storage_events_times_pruned_extremities{instance=\"$instance\",job=~\"$job\",index=~\"$index\"}[$bucket_size]))",
               "interval": "",
               "legendFormat": "Pruned",
@@ -9413,9 +10215,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Stale extremity dropping",
           "tooltip": {
             "shared": true,
@@ -9424,47 +10224,50 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         }
       ],
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "000000001"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Extremities",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
         "x": 0,
-        "y": 40
+        "y": 41
       },
       "id": 158,
       "panels": [
@@ -9473,7 +10276,9 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
               "custom": {},
@@ -9525,6 +10330,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_admin_mau:current{instance=\"$instance\", job=~\"$job\"}",
               "format": "time_series",
               "interval": "",
@@ -9533,6 +10341,9 @@
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_admin_mau:max{instance=\"$instance\", job=~\"$job\"}",
               "format": "time_series",
               "interval": "",
@@ -9542,9 +10353,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "MAU Limits",
           "tooltip": {
             "shared": true,
@@ -9553,33 +10362,27 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
+              "$$hashKey": "object:176",
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             },
             {
+              "$$hashKey": "object:177",
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -9587,7 +10390,9 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
               "custom": {}
@@ -9630,6 +10435,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "synapse_admin_mau_current_mau_by_service{instance=\"$instance\"}",
               "interval": "",
               "legendFormat": "{{ app_service }}",
@@ -9637,9 +10445,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "MAU by Appservice",
           "tooltip": {
             "shared": true,
@@ -9648,47 +10454,50 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         }
       ],
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "000000001"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "MAU",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
         "x": 0,
-        "y": 41
+        "y": 42
       },
       "id": 177,
       "panels": [
@@ -9697,7 +10506,9 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
               "custom": {},
@@ -9739,6 +10550,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_notifier_users_woken_by_stream{job=\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
               "format": "time_series",
               "hide": false,
@@ -9750,9 +10564,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Notifier Streams Woken",
           "tooltip": {
             "shared": true,
@@ -9761,33 +10573,24 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -9795,7 +10598,9 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
               "custom": {},
@@ -9837,6 +10642,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_handler_presence_get_updates{job=~\"$job\",instance=\"$instance\"}[$bucket_size])",
               "format": "time_series",
               "interval": "",
@@ -9847,9 +10655,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Presence Stream Fetch Type Rates",
           "tooltip": {
             "shared": true,
@@ -9858,47 +10664,51 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
               "min": "0",
               "show": true
             },
             {
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         }
       ],
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "000000001"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Notifier",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
         "x": 0,
-        "y": 42
+        "y": 43
       },
       "id": 170,
       "panels": [
@@ -9907,12 +10717,8 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
-          "fieldConfig": {
-            "defaults": {
-              "custom": {}
-            },
-            "overrides": []
+          "datasource": {
+            "uid": "$datasource"
           },
           "fill": 1,
           "fillGradient": 0,
@@ -9940,7 +10746,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "8.3.2",
           "pointradius": 2,
           "points": false,
           "renderer": "flot",
@@ -9950,6 +10756,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_appservice_api_sent_events{instance=\"$instance\"}[$bucket_size])",
               "interval": "",
               "legendFormat": "{{service}}",
@@ -9957,9 +10766,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Sent Events rate",
           "tooltip": {
             "shared": true,
@@ -9968,33 +10775,26 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
+              "$$hashKey": "object:177",
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
+              "$$hashKey": "object:178",
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -10002,12 +10802,8 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
-          "fieldConfig": {
-            "defaults": {
-              "custom": {}
-            },
-            "overrides": []
+          "datasource": {
+            "uid": "$datasource"
           },
           "fill": 1,
           "fillGradient": 0,
@@ -10035,7 +10831,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "8.3.2",
           "pointradius": 2,
           "points": false,
           "renderer": "flot",
@@ -10045,16 +10841,17 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_appservice_api_sent_transactions{instance=\"$instance\"}[$bucket_size])",
               "interval": "",
-              "legendFormat": "{{service}}",
+              "legendFormat": "{{exported_service }} {{ service }}",
               "refId": "A"
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Transactions rate",
           "tooltip": {
             "shared": true,
@@ -10063,47 +10860,52 @@
           },
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           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
+              "$$hashKey": "object:260",
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
+              "$$hashKey": "object:261",
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         }
       ],
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "000000001"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Appservices",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
         "x": 0,
-        "y": 43
+        "y": 44
       },
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       "panels": [
@@ -10112,7 +10914,9 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
               "custom": {}
@@ -10155,30 +10959,45 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_handler_presence_notified_presence{job=\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
               "interval": "",
               "legendFormat": "Notified",
               "refId": "A"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_handler_presence_federation_presence_out{job=\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
               "interval": "",
               "legendFormat": "Remote ping",
               "refId": "B"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_handler_presence_presence_updates{job=\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
               "interval": "",
               "legendFormat": "Total updates",
               "refId": "C"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_handler_presence_federation_presence{job=\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
               "interval": "",
               "legendFormat": "Remote updates",
               "refId": "D"
             },
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_handler_presence_bump_active_time{job=\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
               "interval": "",
               "legendFormat": "Bump active time",
@@ -10186,9 +11005,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Presence",
           "tooltip": {
             "shared": true,
@@ -10197,33 +11014,24 @@
           },
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           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
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             "values": []
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-              "min": null,
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-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
@@ -10231,7 +11039,9 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
               "custom": {}
@@ -10274,6 +11084,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_handler_presence_state_transition{job=\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
               "interval": "",
               "legendFormat": "{{from}} -> {{to}}",
@@ -10281,9 +11094,7 @@
             }
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           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Presence state transitions",
           "tooltip": {
             "shared": true,
@@ -10292,33 +11103,24 @@
           },
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-            "buckets": null,
             "mode": "time",
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               "format": "hertz",
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-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
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         {
@@ -10326,7 +11128,9 @@
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
               "custom": {}
@@ -10369,6 +11173,9 @@
           "steppedLine": false,
           "targets": [
             {
+              "datasource": {
+                "uid": "$datasource"
+              },
               "expr": "rate(synapse_handler_presence_notify_reason{job=\"$job\",index=~\"$index\",instance=\"$instance\"}[$bucket_size])",
               "interval": "",
               "legendFormat": "{{reason}}",
@@ -10376,9 +11183,7 @@
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "Presence  notify reason",
           "tooltip": {
             "shared": true,
@@ -10387,165 +11192,162 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
+              "$$hashKey": "object:165",
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
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+              "$$hashKey": "object:166",
               "format": "short",
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-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         }
       ],
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "000000001"
+          },
+          "refId": "A"
+        }
+      ],
       "title": "Presence",
       "type": "row"
     },
     {
       "collapsed": true,
-      "datasource": "${DS_PROMETHEUS}",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "gridPos": {
         "h": 1,
         "w": 24,
         "x": 0,
-        "y": 44
+        "y": 45
       },
       "id": 197,
       "panels": [
         {
-          "aliasColors": {},
-          "bars": false,
-          "dashLength": 10,
-          "dashes": false,
-          "datasource": "$datasource",
+          "datasource": {
+            "type": "prometheus",
+            "uid": "$datasource"
+          },
           "fieldConfig": {
             "defaults": {
-              "custom": {}
+              "color": {
+                "mode": "palette-classic"
+              },
+              "custom": {
+                "axisLabel": "",
+                "axisPlacement": "auto",
+                "barAlignment": 0,
+                "drawStyle": "line",
+                "fillOpacity": 10,
+                "gradientMode": "none",
+                "hideFrom": {
+                  "legend": false,
+                  "tooltip": false,
+                  "viz": false
+                },
+                "lineInterpolation": "linear",
+                "lineWidth": 1,
+                "pointSize": 5,
+                "scaleDistribution": {
+                  "type": "linear"
+                },
+                "showPoints": "never",
+                "spanNulls": false,
+                "stacking": {
+                  "group": "A",
+                  "mode": "none"
+                },
+                "thresholdsStyle": {
+                  "mode": "off"
+                }
+              },
+              "mappings": [],
+              "thresholds": {
+                "mode": "absolute",
+                "steps": [
+                  {
+                    "color": "green"
+                  },
+                  {
+                    "color": "red",
+                    "value": 80
+                  }
+                ]
+              },
+              "unit": "hertz"
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-          "fill": 1,
-          "fillGradient": 0,
           "gridPos": {
             "h": 8,
             "w": 12,
             "x": 0,
-            "y": 1
+            "y": 46
           },
-          "hiddenSeries": false,
           "id": 191,
-          "legend": {
-            "avg": false,
-            "current": false,
-            "max": false,
-            "min": false,
-            "show": true,
-            "total": false,
-            "values": false
-          },
-          "lines": true,
-          "linewidth": 1,
-          "nullPointMode": "null",
           "options": {
-            "alertThreshold": true
+            "legend": {
+              "calcs": [],
+              "displayMode": "list",
+              "placement": "bottom"
+            },
+            "tooltip": {
+              "mode": "multi",
+              "sort": "desc"
+            }
           },
-          "percentage": false,
-          "pluginVersion": "7.3.7",
-          "pointradius": 2,
-          "points": false,
-          "renderer": "flot",
-          "seriesOverrides": [],
-          "spaceLength": 10,
-          "stack": false,
-          "steppedLine": false,
+          "pluginVersion": "9.0.4",
           "targets": [
             {
-              "expr": "rate(synapse_external_cache_set{job=\"$job\", instance=\"$instance\", index=~\"$index\"}[$bucket_size])",
+              "datasource": {
+                "uid": "$datasource"
+              },
+              "editorMode": "code",
+              "expr": "rate(synapse_external_cache_set{job=~\"$job\", instance=\"$instance\", index=~\"$index\"}[$bucket_size])",
               "interval": "",
-              "legendFormat": "{{ cache_name }} {{ index }}",
+              "legendFormat": "{{ cache_name }} {{job}}-{{ index }}",
+              "range": true,
               "refId": "A"
             }
           ],
-          "thresholds": [],
-          "timeFrom": null,
-          "timeRegions": [],
-          "timeShift": null,
           "title": "External Cache Set Rate",
-          "tooltip": {
-            "shared": true,
-            "sort": 2,
-            "value_type": "individual"
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-          "xaxis": {
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-            "mode": "time",
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-            "show": true,
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-              "show": true
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-              "min": null,
-              "show": true
-            }
-          ],
-          "yaxis": {
-            "align": false,
-            "alignLevel": null
-          }
+          "type": "timeseries"
         },
         {
           "aliasColors": {},
           "bars": false,
           "dashLength": 10,
           "dashes": false,
-          "datasource": "$datasource",
-          "description": "",
-          "fieldConfig": {
-            "defaults": {
-              "custom": {}
-            },
-            "overrides": []
+          "datasource": {
+            "type": "prometheus",
+            "uid": "$datasource"
           },
+          "description": "",
           "fill": 1,
           "fillGradient": 0,
           "gridPos": {
             "h": 8,
             "w": 12,
             "x": 12,
-            "y": 1
+            "y": 46
           },
           "hiddenSeries": false,
           "id": 193,
@@ -10565,7 +11367,7 @@
             "alertThreshold": true
           },
           "percentage": false,
-          "pluginVersion": "7.3.7",
+          "pluginVersion": "9.0.4",
           "pointradius": 2,
           "points": false,
           "renderer": "flot",
@@ -10575,16 +11377,19 @@
           "steppedLine": false,
           "targets": [
             {
-              "expr": "rate(synapse_external_cache_get{job=\"$job\", instance=\"$instance\", index=~\"$index\"}[$bucket_size])",
+              "datasource": {
+                "uid": "$datasource"
+              },
+              "editorMode": "code",
+              "expr": "sum without (hit) (rate(synapse_external_cache_get{job=~\"$job\", instance=\"$instance\", index=~\"$index\"}[$bucket_size]))",
               "interval": "",
-              "legendFormat": "{{ cache_name }} {{ index }}",
+              "legendFormat": "{{ cache_name }} {{job}}-{{ index }}",
+              "range": true,
               "refId": "A"
             }
           ],
           "thresholds": [],
-          "timeFrom": null,
           "timeRegions": [],
-          "timeShift": null,
           "title": "External Cache Get Rate",
           "tooltip": {
             "shared": true,
@@ -10593,39 +11398,31 @@
           },
           "type": "graph",
           "xaxis": {
-            "buckets": null,
             "mode": "time",
-            "name": null,
             "show": true,
             "values": []
           },
           "yaxes": [
             {
+              "$$hashKey": "object:390",
               "format": "hertz",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             },
             {
+              "$$hashKey": "object:391",
               "format": "short",
-              "label": null,
               "logBase": 1,
-              "max": null,
-              "min": null,
               "show": true
             }
           ],
           "yaxis": {
-            "align": false,
-            "alignLevel": null
+            "align": false
           }
         },
         {
           "cards": {
-            "cardPadding": -1,
-            "cardRound": null
+            "cardPadding": -1
           },
           "color": {
             "cardColor": "#b4ff00",
@@ -10636,18 +11433,15 @@
             "mode": "spectrum"
           },
           "dataFormat": "tsbuckets",
-          "datasource": "$datasource",
-          "fieldConfig": {
-            "defaults": {
-              "custom": {}
-            },
-            "overrides": []
+          "datasource": {
+            "type": "prometheus",
+            "uid": "$datasource"
           },
           "gridPos": {
-            "h": 9,
+            "h": 8,
             "w": 12,
             "x": 0,
-            "y": 9
+            "y": 54
           },
           "heatmap": {},
           "hideZeroBuckets": false,
@@ -10660,7 +11454,10 @@
           "reverseYBuckets": false,
           "targets": [
             {
-              "expr": "sum(rate(synapse_external_cache_response_time_seconds_bucket{index=~\"$index\",instance=\"$instance\",job=\"$job\"}[$bucket_size])) by (le)",
+              "datasource": {
+                "uid": "$datasource"
+              },
+              "expr": "sum(rate(synapse_external_cache_response_time_seconds_bucket{index=~\"$index\",instance=\"$instance\",job=~\"$job\"}[$bucket_size])) by (le)",
               "format": "heatmap",
               "instant": false,
               "interval": "",
@@ -10679,20 +11476,109 @@
           "xAxis": {
             "show": true
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-          "xBucketNumber": null,
-          "xBucketSize": null,
           "yAxis": {
             "decimals": 0,
             "format": "s",
             "logBase": 1,
-            "max": null,
-            "min": null,
-            "show": true,
-            "splitFactor": null
+            "show": true
+          },
+          "yBucketBound": "auto"
+        },
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "$datasource"
+          },
+          "description": "",
+          "fieldConfig": {
+            "defaults": {
+              "color": {
+                "mode": "palette-classic"
+              },
+              "custom": {
+                "axisLabel": "",
+                "axisPlacement": "auto",
+                "barAlignment": 0,
+                "drawStyle": "line",
+                "fillOpacity": 10,
+                "gradientMode": "none",
+                "hideFrom": {
+                  "legend": false,
+                  "tooltip": false,
+                  "viz": false
+                },
+                "lineInterpolation": "linear",
+                "lineWidth": 1,
+                "pointSize": 5,
+                "scaleDistribution": {
+                  "type": "linear"
+                },
+                "showPoints": "never",
+                "spanNulls": false,
+                "stacking": {
+                  "group": "A",
+                  "mode": "none"
+                },
+                "thresholdsStyle": {
+                  "mode": "off"
+                }
+              },
+              "mappings": [],
+              "thresholds": {
+                "mode": "absolute",
+                "steps": [
+                  {
+                    "color": "green"
+                  }
+                ]
+              },
+              "unit": "hertz"
+            },
+            "overrides": []
           },
-          "yBucketBound": "auto",
-          "yBucketNumber": null,
-          "yBucketSize": null
+          "gridPos": {
+            "h": 8,
+            "w": 12,
+            "x": 12,
+            "y": 54
+          },
+          "id": 223,
+          "options": {
+            "legend": {
+              "calcs": [],
+              "displayMode": "list",
+              "placement": "bottom"
+            },
+            "tooltip": {
+              "mode": "multi",
+              "sort": "desc"
+            }
+          },
+          "pluginVersion": "9.0.4",
+          "targets": [
+            {
+              "datasource": {
+                "uid": "$datasource"
+              },
+              "editorMode": "code",
+              "expr": "rate(synapse_external_cache_get{job=~\"$job\", instance=\"$instance\", index=~\"$index\", hit=\"False\"}[$bucket_size])",
+              "interval": "",
+              "legendFormat": "{{ cache_name }} {{job}}-{{ index }}",
+              "range": true,
+              "refId": "A"
+            }
+          ],
+          "title": "External Cache Miss Rate",
+          "type": "timeseries"
+        }
+      ],
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "000000001"
+          },
+          "refId": "A"
         }
       ],
       "title": "External Cache",
@@ -10700,7 +11586,7 @@
     }
   ],
   "refresh": false,
-  "schemaVersion": 26,
+  "schemaVersion": 36,
   "style": "dark",
   "tags": [
     "matrix"
@@ -10713,10 +11599,8 @@
           "text": "default",
           "value": "default"
         },
-        "error": null,
         "hide": 0,
         "includeAll": false,
-        "label": null,
         "multi": false,
         "name": "datasource",
         "options": [],
@@ -10731,14 +11615,12 @@
         "allFormat": "glob",
         "auto": true,
         "auto_count": 100,
-        "auto_min": "60s",
+        "auto_min": "30s",
         "current": {
           "selected": false,
           "text": "auto",
           "value": "$__auto_interval_bucket_size"
         },
-        "datasource": null,
-        "error": null,
         "hide": 0,
         "includeAll": false,
         "label": "Bucket Size",
@@ -10789,24 +11671,25 @@
         "type": "interval"
       },
       {
-        "allValue": null,
         "current": {},
-        "datasource": "$datasource",
+        "datasource": {
+          "uid": "$datasource"
+        },
         "definition": "",
-        "error": null,
         "hide": 0,
         "includeAll": false,
-        "label": null,
         "multi": false,
         "name": "instance",
         "options": [],
-        "query": "label_values(synapse_util_metrics_block_ru_utime_seconds, instance)",
+        "query": {
+          "query": "label_values(synapse_util_metrics_block_ru_utime_seconds, instance)",
+          "refId": "Prometheus-instance-Variable-Query"
+        },
         "refresh": 2,
         "regex": "",
         "skipUrlSync": false,
         "sort": 1,
         "tagValuesQuery": "",
-        "tags": [],
         "tagsQuery": "",
         "type": "query",
         "useTags": false
@@ -10815,9 +11698,10 @@
         "allFormat": "regex wildcard",
         "allValue": "",
         "current": {},
-        "datasource": "$datasource",
+        "datasource": {
+          "uid": "$datasource"
+        },
         "definition": "",
-        "error": null,
         "hide": 0,
         "hideLabel": false,
         "includeAll": true,
@@ -10826,14 +11710,16 @@
         "multiFormat": "regex values",
         "name": "job",
         "options": [],
-        "query": "label_values(synapse_util_metrics_block_ru_utime_seconds, job)",
+        "query": {
+          "query": "label_values(synapse_util_metrics_block_ru_utime_seconds, job)",
+          "refId": "Prometheus-job-Variable-Query"
+        },
         "refresh": 2,
         "refresh_on_load": false,
         "regex": "",
         "skipUrlSync": false,
         "sort": 1,
         "tagValuesQuery": "",
-        "tags": [],
         "tagsQuery": "",
         "type": "query",
         "useTags": false
@@ -10842,9 +11728,10 @@
         "allFormat": "regex wildcard",
         "allValue": ".*",
         "current": {},
-        "datasource": "$datasource",
+        "datasource": {
+          "uid": "$datasource"
+        },
         "definition": "",
-        "error": null,
         "hide": 0,
         "hideLabel": false,
         "includeAll": true,
@@ -10853,14 +11740,16 @@
         "multiFormat": "regex values",
         "name": "index",
         "options": [],
-        "query": "label_values(synapse_util_metrics_block_ru_utime_seconds, index)",
+        "query": {
+          "query": "label_values(synapse_util_metrics_block_ru_utime_seconds, index)",
+          "refId": "Prometheus-index-Variable-Query"
+        },
         "refresh": 2,
         "refresh_on_load": false,
         "regex": "",
         "skipUrlSync": false,
         "sort": 3,
         "tagValuesQuery": "",
-        "tags": [],
         "tagsQuery": "",
         "type": "query",
         "useTags": false
@@ -10868,8 +11757,8 @@
     ]
   },
   "time": {
-    "from": "now-3h",
-    "to": "now"
+    "from": "2022-07-22T04:08:13.716Z",
+    "to": "2022-07-22T18:44:27.863Z"
   },
   "timepicker": {
     "now": true,
@@ -10900,5 +11789,6 @@
   "timezone": "",
   "title": "Synapse",
   "uid": "000000012",
-  "version": 100
-}
+  "version": 124,
+  "weekStart": ""
+}
\ No newline at end of file
diff --git a/debian/changelog b/debian/changelog
index 9417f8714f..c3974261a9 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,45 @@
+matrix-synapse-py3 (1.66.0~rc1) stable; urgency=medium
+
+  * New Synapse release 1.66.0rc1.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 23 Aug 2022 09:48:55 +0100
+
+matrix-synapse-py3 (1.65.0) stable; urgency=medium
+
+  * New Synapse release 1.65.0.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 16 Aug 2022 16:51:26 +0100
+
+matrix-synapse-py3 (1.65.0~rc2) stable; urgency=medium
+
+  * New Synapse release 1.65.0rc2.
+
+ -- Synapse Packaging team <packages@matrix.org>  Thu, 11 Aug 2022 11:38:18 +0100
+
+matrix-synapse-py3 (1.65.0~rc1) stable; urgency=medium
+
+  * New Synapse release 1.65.0rc1.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 09 Aug 2022 11:39:29 +0100
+
+matrix-synapse-py3 (1.64.0) stable; urgency=medium
+
+  * New Synapse release 1.64.0.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 02 Aug 2022 10:32:30 +0100
+
+matrix-synapse-py3 (1.64.0~rc2) stable; urgency=medium
+
+  * New Synapse release 1.64.0rc2.
+
+ -- Synapse Packaging team <packages@matrix.org>  Fri, 29 Jul 2022 12:22:53 +0100
+
+matrix-synapse-py3 (1.64.0~rc1) stable; urgency=medium
+
+  * New Synapse release 1.64.0rc1.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 26 Jul 2022 12:11:49 +0100
+
 matrix-synapse-py3 (1.63.1) stable; urgency=medium
 
   * New Synapse release 1.63.1.
diff --git a/docker/Dockerfile b/docker/Dockerfile
index f4d8e6c925..fa58ae3acb 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -40,7 +40,8 @@ FROM docker.io/python:${PYTHON_VERSION}-slim as requirements
 RUN \
    --mount=type=cache,target=/var/cache/apt,sharing=locked \
    --mount=type=cache,target=/var/lib/apt,sharing=locked \
- apt-get update -qq && apt-get install -yqq git \
+    apt-get update -qq && apt-get install -yqq \
+      build-essential cargo git libffi-dev libssl-dev \
     && rm -rf /var/lib/apt/lists/*
 
 # We install poetry in its own build stage to avoid its dependencies conflicting with
@@ -68,7 +69,18 @@ COPY pyproject.toml poetry.lock /synapse/
 # reason, such as when a git repository is used directly as a dependency.
 ARG TEST_ONLY_SKIP_DEP_HASH_VERIFICATION
 
-RUN /root/.local/bin/poetry export --extras all -o /synapse/requirements.txt ${TEST_ONLY_SKIP_DEP_HASH_VERIFICATION:+--without-hashes}
+# If specified, we won't use the Poetry lockfile.
+# Instead, we'll just install what a regular `pip install` would from PyPI.
+ARG TEST_ONLY_IGNORE_POETRY_LOCKFILE
+
+# Export the dependencies, but only if we're actually going to use the Poetry lockfile.
+# Otherwise, just create an empty requirements file so that the Dockerfile can
+# proceed.
+RUN if [ -z "$TEST_ONLY_IGNORE_POETRY_LOCKFILE" ]; then \
+    /root/.local/bin/poetry export --extras all -o /synapse/requirements.txt ${TEST_ONLY_SKIP_DEP_HASH_VERIFICATION:+--without-hashes}; \
+  else \
+    touch /synapse/requirements.txt; \
+  fi
 
 ###
 ### Stage 1: builder
@@ -108,8 +120,17 @@ COPY synapse /synapse/synapse/
 # ... and what we need to `pip install`.
 COPY pyproject.toml README.rst /synapse/
 
+# Repeat of earlier build argument declaration, as this is a new build stage.
+ARG TEST_ONLY_IGNORE_POETRY_LOCKFILE
+
 # Install the synapse package itself.
-RUN pip install --prefix="/install" --no-deps --no-warn-script-location /synapse
+# If we have populated requirements.txt, we don't install any dependencies
+# as we should already have those from the previous `pip install` step.
+RUN if [ -z "$TEST_ONLY_IGNORE_POETRY_LOCKFILE" ]; then \
+    pip install --prefix="/install" --no-deps --no-warn-script-location /synapse[all]; \
+  else \
+    pip install --prefix="/install" --no-warn-script-location /synapse[all]; \
+  fi
 
 ###
 ### Stage 2: runtime
diff --git a/docker/Dockerfile-workers b/docker/Dockerfile-workers
index 0f1570cfb6..003a1cc3bf 100644
--- a/docker/Dockerfile-workers
+++ b/docker/Dockerfile-workers
@@ -1,38 +1,62 @@
-# Inherit from the official Synapse docker image
-ARG SYNAPSE_VERSION=latest
-FROM matrixdotorg/synapse:$SYNAPSE_VERSION
-
-# Install deps
-RUN \
-   --mount=type=cache,target=/var/cache/apt,sharing=locked \
-   --mount=type=cache,target=/var/lib/apt,sharing=locked \
-  apt-get update -qq && \
-  DEBIAN_FRONTEND=noninteractive apt-get install -yqq --no-install-recommends \
-     redis-server nginx-light
-
-# Install supervisord with pip instead of apt, to avoid installing a second
-# copy of python.
-RUN --mount=type=cache,target=/root/.cache/pip \
-    pip install supervisor~=4.2
-
-# Disable the default nginx sites
-RUN rm /etc/nginx/sites-enabled/default
+# syntax=docker/dockerfile:1
 
-# Copy Synapse worker, nginx and supervisord configuration template files
-COPY ./docker/conf-workers/* /conf/
-
-# Copy a script to prefix log lines with the supervisor program name
-COPY ./docker/prefix-log /usr/local/bin/
-
-# Expose nginx listener port
-EXPOSE 8080/tcp
+ARG SYNAPSE_VERSION=latest
 
-# A script to read environment variables and create the necessary
-# files to run the desired worker configuration. Will start supervisord.
-COPY ./docker/configure_workers_and_start.py /configure_workers_and_start.py
-ENTRYPOINT ["/configure_workers_and_start.py"]
+# first of all, we create a base image with an nginx which we can copy into the
+# target image. For repeated rebuilds, this is much faster than apt installing
+# each time.
+
+FROM debian:bullseye-slim AS deps_base
+    RUN \
+       --mount=type=cache,target=/var/cache/apt,sharing=locked \
+       --mount=type=cache,target=/var/lib/apt,sharing=locked \
+      apt-get update -qq && \
+      DEBIAN_FRONTEND=noninteractive apt-get install -yqq --no-install-recommends \
+          redis-server nginx-light
+
+# Similarly, a base to copy the redis server from.
+#
+# The redis docker image has fewer dynamic libraries than the debian package,
+# which makes it much easier to copy (but we need to make sure we use an image
+# based on the same debian version as the synapse image, to make sure we get
+# the expected version of libc.
+FROM redis:6-bullseye AS redis_base
+
+# now build the final image, based on the the regular Synapse docker image
+FROM matrixdotorg/synapse:$SYNAPSE_VERSION
 
-# Replace the healthcheck with one which checks *all* the workers. The script
-# is generated by configure_workers_and_start.py.
-HEALTHCHECK --start-period=5s --interval=15s --timeout=5s \
-    CMD /bin/sh /healthcheck.sh
+    # Install supervisord with pip instead of apt, to avoid installing a second
+    # copy of python.
+    RUN --mount=type=cache,target=/root/.cache/pip \
+        pip install supervisor~=4.2
+    RUN mkdir -p /etc/supervisor/conf.d
+
+    # Copy over redis and nginx
+    COPY --from=redis_base /usr/local/bin/redis-server /usr/local/bin
+
+    COPY --from=deps_base /usr/sbin/nginx /usr/sbin
+    COPY --from=deps_base /usr/share/nginx /usr/share/nginx
+    COPY --from=deps_base /usr/lib/nginx /usr/lib/nginx
+    COPY --from=deps_base /etc/nginx /etc/nginx
+    RUN rm /etc/nginx/sites-enabled/default
+    RUN mkdir /var/log/nginx /var/lib/nginx
+    RUN chown www-data /var/log/nginx /var/lib/nginx
+
+    # Copy Synapse worker, nginx and supervisord configuration template files
+    COPY ./docker/conf-workers/* /conf/
+
+    # Copy a script to prefix log lines with the supervisor program name
+    COPY ./docker/prefix-log /usr/local/bin/
+
+    # Expose nginx listener port
+    EXPOSE 8080/tcp
+
+    # A script to read environment variables and create the necessary
+    # files to run the desired worker configuration. Will start supervisord.
+    COPY ./docker/configure_workers_and_start.py /configure_workers_and_start.py
+    ENTRYPOINT ["/configure_workers_and_start.py"]
+
+    # Replace the healthcheck with one which checks *all* the workers. The script
+    # is generated by configure_workers_and_start.py.
+    HEALTHCHECK --start-period=5s --interval=15s --timeout=5s \
+        CMD /bin/sh /healthcheck.sh
diff --git a/docker/README-testing.md b/docker/README-testing.md
index 1f0423f09b..21b99963d8 100644
--- a/docker/README-testing.md
+++ b/docker/README-testing.md
@@ -22,6 +22,10 @@ Consult the [contributing guide][guideComplementSh] for instructions on how to u
 Under some circumstances, you may wish to build the images manually.
 The instructions below will lead you to doing that.
 
+Note that these images can only be built using [BuildKit](https://docs.docker.com/develop/develop-images/build_enhancements/),
+therefore BuildKit needs to be enabled when calling `docker build`. This can be done by
+setting `DOCKER_BUILDKIT=1` in your environment.
+
 Start by building the base Synapse docker image. If you wish to run tests with the latest
 release of Synapse, instead of your current checkout, you can skip this step. From the
 root of the repository:
diff --git a/docker/README.md b/docker/README.md
index 5b7de2fe38..017f046c58 100644
--- a/docker/README.md
+++ b/docker/README.md
@@ -191,7 +191,7 @@ If you need to build the image from a Synapse checkout, use the following `docke
  build` command from the repo's root:
 
 ```
-docker build -t matrixdotorg/synapse -f docker/Dockerfile .
+DOCKER_BUILDKIT=1 docker build -t matrixdotorg/synapse -f docker/Dockerfile .
 ```
 
 You can choose to build a different docker image by changing the value of the `-f` flag to
diff --git a/docker/complement/Dockerfile b/docker/complement/Dockerfile
index c5e7984a28..3cfff19f9a 100644
--- a/docker/complement/Dockerfile
+++ b/docker/complement/Dockerfile
@@ -1,3 +1,4 @@
+# syntax=docker/dockerfile:1
 # This dockerfile builds on top of 'docker/Dockerfile-workers' in matrix-org/synapse
 # by including a built-in postgres instance, as well as setting up the homeserver so
 # that it is ready for testing via Complement.
diff --git a/docker/conf-workers/supervisord.conf.j2 b/docker/conf-workers/supervisord.conf.j2
index 086137494e..9f1e03cfc0 100644
--- a/docker/conf-workers/supervisord.conf.j2
+++ b/docker/conf-workers/supervisord.conf.j2
@@ -19,7 +19,7 @@ username=www-data
 autorestart=true
 
 [program:redis]
-command=/usr/local/bin/prefix-log /usr/bin/redis-server /etc/redis/redis.conf --daemonize no
+command=/usr/local/bin/prefix-log /usr/local/bin/redis-server
 priority=1
 stdout_logfile=/dev/stdout
 stdout_logfile_maxbytes=0
diff --git a/docs/admin_api/register_api.md b/docs/admin_api/register_api.md
index c346090bb1..d7b7cf6a76 100644
--- a/docs/admin_api/register_api.md
+++ b/docs/admin_api/register_api.md
@@ -46,7 +46,24 @@ As an example:
 The MAC is the hex digest output of the HMAC-SHA1 algorithm, with the key being
 the shared secret and the content being the nonce, user, password, either the
 string "admin" or "notadmin", and optionally the user_type
-each separated by NULs. For an example of generation in Python:
+each separated by NULs.
+
+Here is an easy way to generate the HMAC digest if you have Bash and OpenSSL:
+
+```bash
+# Update these values and then paste this code block into a bash terminal
+nonce='thisisanonce'
+username='pepper_roni'
+password='pizza'
+admin='admin'
+secret='shared_secret'
+
+printf '%s\0%s\0%s\0%s' "$nonce" "$username" "$password" "$admin" |
+  openssl sha1 -hmac "$secret" |
+  awk '{print $2}'
+```
+
+For an example of generation in Python:
 
 ```python
 import hmac, hashlib
@@ -70,4 +87,4 @@ def generate_mac(nonce, user, password, admin=False, user_type=None):
         mac.update(user_type.encode('utf8'))
 
     return mac.hexdigest()
-```
\ No newline at end of file
+```
diff --git a/docs/admin_api/rooms.md b/docs/admin_api/rooms.md
index 9aa489e4a3..7526956bec 100644
--- a/docs/admin_api/rooms.md
+++ b/docs/admin_api/rooms.md
@@ -302,6 +302,8 @@ The following fields are possible in the JSON response body:
 * `state_events` - Total number of state_events of a room. Complexity of the room.
 * `room_type` - The type of the room taken from the room's creation event; for example "m.space" if the room is a space.
   If the room does not define a type, the value will be `null`.
+* `forgotten` - Whether all local users have
+  [forgotten](https://spec.matrix.org/latest/client-server-api/#leaving-rooms) the room.
 
 The API is:
 
@@ -330,10 +332,13 @@ A response body like the following is returned:
   "guest_access": null,
   "history_visibility": "shared",
   "state_events": 93534,
-  "room_type": "m.space"
+  "room_type": "m.space",
+  "forgotten": false
 }
 ```
 
+_Changed in Synapse 1.66:_ Added the `forgotten` key to the response body.
+
 # Room Members API
 
 The Room Members admin API allows server admins to get a list of all members of a room.
diff --git a/docs/admin_api/user_admin_api.md b/docs/admin_api/user_admin_api.md
index 0871cfebf5..c1ca0c8a64 100644
--- a/docs/admin_api/user_admin_api.md
+++ b/docs/admin_api/user_admin_api.md
@@ -753,6 +753,7 @@ A response body like the following is returned:
       "device_id": "QBUAZIFURK",
       "display_name": "android",
       "last_seen_ip": "1.2.3.4",
+      "last_seen_user_agent": "Mozilla/5.0 (X11; Linux x86_64; rv:103.0) Gecko/20100101 Firefox/103.0",
       "last_seen_ts": 1474491775024,
       "user_id": "<user_id>"
     },
@@ -760,6 +761,7 @@ A response body like the following is returned:
       "device_id": "AUIECTSRND",
       "display_name": "ios",
       "last_seen_ip": "1.2.3.5",
+      "last_seen_user_agent": "Mozilla/5.0 (X11; Linux x86_64; rv:103.0) Gecko/20100101 Firefox/103.0",
       "last_seen_ts": 1474491775025,
       "user_id": "<user_id>"
     }
@@ -786,6 +788,8 @@ The following fields are returned in the JSON response body:
     Absent if no name has been set.
   - `last_seen_ip` - The IP address where this device was last seen.
     (May be a few minutes out of date, for efficiency reasons).
+  - `last_seen_user_agent` - The user agent of the device when it was last seen.
+    (May be a few minutes out of date, for efficiency reasons).
   - `last_seen_ts` - The timestamp (in milliseconds since the unix epoch) when this
     devices was last seen. (May be a few minutes out of date, for efficiency reasons).
   - `user_id` - Owner of  device.
@@ -837,6 +841,7 @@ A response body like the following is returned:
   "device_id": "<device_id>",
   "display_name": "android",
   "last_seen_ip": "1.2.3.4",
+  "last_seen_user_agent": "Mozilla/5.0 (X11; Linux x86_64; rv:103.0) Gecko/20100101 Firefox/103.0",
   "last_seen_ts": 1474491775024,
   "user_id": "<user_id>"
 }
@@ -858,6 +863,8 @@ The following fields are returned in the JSON response body:
   Absent if no name has been set.
 - `last_seen_ip` - The IP address where this device was last seen.
   (May be a few minutes out of date, for efficiency reasons).
+  - `last_seen_user_agent` - The user agent of the device when it was last seen.
+  (May be a few minutes out of date, for efficiency reasons).
 - `last_seen_ts` - The timestamp (in milliseconds since the unix epoch) when this
   devices was last seen. (May be a few minutes out of date, for efficiency reasons).
 - `user_id` - Owner of  device.
diff --git a/docs/auth_chain_difference_algorithm.md b/docs/auth_chain_difference_algorithm.md
index 30f72a70da..ebc9de25b8 100644
--- a/docs/auth_chain_difference_algorithm.md
+++ b/docs/auth_chain_difference_algorithm.md
@@ -34,13 +34,45 @@ the process of indexing it).
 ## Chain Cover Index
 
 Synapse computes auth chain differences by pre-computing a "chain cover" index
-for the auth chain in a room, allowing efficient reachability queries like "is
-event A in the auth chain of event B". This is done by assigning every event a
-*chain ID* and *sequence number* (e.g. `(5,3)`), and having a map of *links*
-between chains (e.g. `(5,3) -> (2,4)`) such that A is reachable by B (i.e. `A`
-is in the auth chain of `B`) if and only if either:
-
-1. A and B have the same chain ID and `A`'s sequence number is less than `B`'s
+for the auth chain in a room, allowing us to efficiently make reachability queries
+like "is event `A` in the auth chain of event `B`?". We could do this with an index
+that tracks all pairs `(A, B)` such that `A` is in the auth chain of `B`. However, this
+would be prohibitively large, scaling poorly as the room accumulates more state
+events.
+
+Instead, we break down the graph into *chains*. A chain is a subset of a DAG
+with the following property: for any pair of events `E` and `F` in the chain,
+the chain contains a path `E -> F` or a path `F -> E`. This forces a chain to be
+linear (without forks), e.g. `E -> F -> G -> ... -> H`. Each event in the chain
+is given a *sequence number* local to that chain. The oldest event `E` in the
+chain has sequence number 1. If `E` has a child `F` in the chain, then `F` has
+sequence number 2. If `E` has a grandchild `G` in the chain, then `G` has
+sequence number 3; and so on.
+
+Synapse ensures that each persisted event belongs to exactly one chain, and
+tracks how the chains are connected to one another. This allows us to
+efficiently answer reachability queries. Doing so uses less storage than
+tracking reachability on an event-by-event basis, particularly when we have
+fewer and longer chains. See
+
+> Jagadish, H. (1990). [A compression technique to materialize transitive closure](https://doi.org/10.1145/99935.99944).
+> *ACM Transactions on Database Systems (TODS)*, 15*(4)*, 558-598.
+
+for the original idea or
+
+> Y. Chen, Y. Chen, [An efficient algorithm for answering graph
+> reachability queries](https://doi.org/10.1109/ICDE.2008.4497498),
+> in: 2008 IEEE 24th International Conference on Data Engineering, April 2008,
+> pp. 893–902. (PDF available via [Google Scholar](https://scholar.google.com/scholar?q=Y.%20Chen,%20Y.%20Chen,%20An%20efficient%20algorithm%20for%20answering%20graph%20reachability%20queries,%20in:%202008%20IEEE%2024th%20International%20Conference%20on%20Data%20Engineering,%20April%202008,%20pp.%20893902.).)
+
+for a more modern take.
+
+In practical terms, the chain cover assigns every event a
+*chain ID* and *sequence number* (e.g. `(5,3)`), and maintains a map of *links*
+between events in chains (e.g. `(5,3) -> (2,4)`) such that `A` is reachable by `B`
+(i.e. `A` is in the auth chain of `B`) if and only if either:
+
+1. `A` and `B` have the same chain ID and `A`'s sequence number is less than `B`'s
    sequence number; or
 2. there is a link `L` between `B`'s chain ID and `A`'s chain ID such that
    `L.start_seq_no` <= `B.seq_no` and `A.seq_no` <= `L.end_seq_no`.
@@ -49,8 +81,9 @@ There are actually two potential implementations, one where we store links from
 each chain to every other reachable chain (the transitive closure of the links
 graph), and one where we remove redundant links (the transitive reduction of the
 links graph) e.g. if we have chains `C3 -> C2 -> C1` then the link `C3 -> C1`
-would not be stored. Synapse uses the former implementations so that it doesn't
-need to recurse to test reachability between chains.
+would not be stored. Synapse uses the former implementation so that it doesn't
+need to recurse to test reachability between chains. This trades-off extra storage
+in order to save CPU cycles and DB queries.
 
 ### Example
 
diff --git a/docs/message_retention_policies.md b/docs/message_retention_policies.md
index 8c88f93935..7f3e5359f1 100644
--- a/docs/message_retention_policies.md
+++ b/docs/message_retention_policies.md
@@ -8,7 +8,8 @@ and allow server and room admins to configure how long messages should
 be kept in a homeserver's database before being purged from it.
 **Please note that, as this feature isn't part of the Matrix
 specification yet, this implementation is to be considered as
-experimental.** 
+experimental. There are known bugs which may cause database corruption.
+Proceed with caution.** 
 
 A message retention policy is mainly defined by its `max_lifetime`
 parameter, which defines how long a message can be kept around after
diff --git a/docs/modules/password_auth_provider_callbacks.md b/docs/modules/password_auth_provider_callbacks.md
index ec810fd292..f6349d5404 100644
--- a/docs/modules/password_auth_provider_callbacks.md
+++ b/docs/modules/password_auth_provider_callbacks.md
@@ -263,7 +263,7 @@ class MyAuthProvider:
             return None
 
         if self.credentials.get(username) == login_dict.get("my_field"):
-            return self.api.get_qualified_user_id(username)
+            return (self.api.get_qualified_user_id(username), None)
 
     async def check_pass(
         self,
@@ -280,5 +280,5 @@ class MyAuthProvider:
             return None
 
         if self.credentials.get(username) == login_dict.get("password"):
-            return self.api.get_qualified_user_id(username)
+            return (self.api.get_qualified_user_id(username), None)
 ```
diff --git a/docs/openid.md b/docs/openid.md
index d0ccf36f71..ce9b026228 100644
--- a/docs/openid.md
+++ b/docs/openid.md
@@ -174,7 +174,9 @@ oidc_providers:
 
 1. Create a regular web application for Synapse
 2. Set the Allowed Callback URLs to `[synapse public baseurl]/_synapse/client/oidc/callback`
-3. Add a rule to add the `preferred_username` claim.
+3. Add a rule with any name to add the `preferred_username` claim. 
+(See https://auth0.com/docs/customize/rules/create-rules for more information on how to create rules.)
+   
    <details>
     <summary>Code sample</summary>
 
diff --git a/docs/reverse_proxy.md b/docs/reverse_proxy.md
index 69caa8a73e..d1618e8155 100644
--- a/docs/reverse_proxy.md
+++ b/docs/reverse_proxy.md
@@ -79,63 +79,32 @@ server {
 }
 ```
 
-### Caddy v1
-
-```
-matrix.example.com {
-  proxy /_matrix http://localhost:8008 {
-    transparent
-  }
-
-  proxy /_synapse/client http://localhost:8008 {
-    transparent
-  }
-}
-
-example.com:8448 {
-  proxy / http://localhost:8008 {
-    transparent
-  }
-}
-```
-
 ### Caddy v2
 
 ```
 matrix.example.com {
-  reverse_proxy /_matrix/* http://localhost:8008
-  reverse_proxy /_synapse/client/* http://localhost:8008
+  reverse_proxy /_matrix/* localhost:8008
+  reverse_proxy /_synapse/client/* localhost:8008
 }
 
 example.com:8448 {
-  reverse_proxy http://localhost:8008
+  reverse_proxy localhost:8008
 }
 ```
+
 [Delegation](delegate.md) example:
-```
-(matrix-well-known-header) {
-    # Headers
-    header Access-Control-Allow-Origin "*"
-    header Access-Control-Allow-Methods "GET, POST, PUT, DELETE, OPTIONS"
-    header Access-Control-Allow-Headers "Origin, X-Requested-With, Content-Type, Accept, Authorization"
-    header Content-Type "application/json"
-}
 
+```
 example.com {
-    handle /.well-known/matrix/server {
-        import matrix-well-known-header
-        respond `{"m.server":"matrix.example.com:443"}`
-    }
-
-    handle /.well-known/matrix/client {
-        import matrix-well-known-header
-        respond `{"m.homeserver":{"base_url":"https://matrix.example.com"},"m.identity_server":{"base_url":"https://identity.example.com"}}`
-    }
+	header /.well-known/matrix/* Content-Type application/json
+	header /.well-known/matrix/* Access-Control-Allow-Origin *
+	respond /.well-known/matrix/server `{"m.server": "matrix.example.com:443"}`
+	respond /.well-known/matrix/client `{"m.homeserver":{"base_url":"https://matrix.example.com"},"m.identity_server":{"base_url":"https://identity.example.com"}}`
 }
 
 matrix.example.com {
-    reverse_proxy /_matrix/* http://localhost:8008
-    reverse_proxy /_synapse/client/* http://localhost:8008
+    reverse_proxy /_matrix/* localhost:8008
+    reverse_proxy /_synapse/client/* localhost:8008
 }
 ```
 
diff --git a/docs/sso_mapping_providers.md b/docs/sso_mapping_providers.md
index 7b4ddc5b74..817499149f 100644
--- a/docs/sso_mapping_providers.md
+++ b/docs/sso_mapping_providers.md
@@ -22,7 +22,7 @@ choose their own username.
 In the first case - where users are automatically allocated a Matrix ID - it is
 the responsibility of the mapping provider to normalise the SSO attributes and
 map them to a valid Matrix ID. The [specification for Matrix
-IDs](https://matrix.org/docs/spec/appendices#user-identifiers) has some
+IDs](https://spec.matrix.org/latest/appendices/#user-identifiers) has some
 information about what is considered valid.
 
 If the mapping provider does not assign a Matrix ID, then Synapse will
@@ -37,9 +37,10 @@ as Synapse). The Synapse config is then modified to point to the mapping provide
 ## OpenID Mapping Providers
 
 The OpenID mapping provider can be customized by editing the
-`oidc_config.user_mapping_provider.module` config option.
+[`oidc_providers.user_mapping_provider.module`](usage/configuration/config_documentation.md#oidc_providers)
+config option.
 
-`oidc_config.user_mapping_provider.config` allows you to provide custom
+`oidc_providers.user_mapping_provider.config` allows you to provide custom
 configuration options to the module. Check with the module's documentation for
 what options it provides (if any). The options listed by default are for the
 user mapping provider built in to Synapse. If using a custom module, you should
@@ -58,7 +59,7 @@ A custom mapping provider must specify the following methods:
     - This method should have the `@staticmethod` decoration.
     - Arguments:
         - `config` - A `dict` representing the parsed content of the
-          `oidc_config.user_mapping_provider.config` homeserver config option.
+          `oidc_providers.user_mapping_provider.config` homeserver config option.
            Runs on homeserver startup. Providers should extract and validate
            any option values they need here.
     - Whatever is returned will be passed back to the user mapping provider module's
@@ -102,7 +103,7 @@ A custom mapping provider must specify the following methods:
       will be returned as part of the response during a successful login.
 
       Note that care should be taken to not overwrite any of the parameters
-      usually returned as part of the [login response](https://matrix.org/docs/spec/client_server/latest#post-matrix-client-r0-login).
+      usually returned as part of the [login response](https://spec.matrix.org/latest/client-server-api/#post_matrixclientv3login).
 
 ### Default OpenID Mapping Provider
 
@@ -113,7 +114,8 @@ specified in the config. It is located at
 ## SAML Mapping Providers
 
 The SAML mapping provider can be customized by editing the
-`saml2_config.user_mapping_provider.module` config option.
+[`saml2_config.user_mapping_provider.module`](docs/usage/configuration/config_documentation.md#saml2_config)
+config option.
 
 `saml2_config.user_mapping_provider.config` allows you to provide custom
 configuration options to the module. Check with the module's documentation for
diff --git a/docs/templates.md b/docs/templates.md
index f87692a453..453ac90dd8 100644
--- a/docs/templates.md
+++ b/docs/templates.md
@@ -9,7 +9,7 @@ in, allowing them to specify custom templates:
 
 ```yaml
 templates:
-  custom_templates_directory: /path/to/custom/templates/
+  custom_template_directory: /path/to/custom/templates/
 ```
 
 If this setting is not set, or the files named below are not found within the directory,
diff --git a/docs/upgrade.md b/docs/upgrade.md
index 2c7c258909..0ab5bfeaf0 100644
--- a/docs/upgrade.md
+++ b/docs/upgrade.md
@@ -89,21 +89,37 @@ process, for example:
     dpkg -i matrix-synapse-py3_1.3.0+stretch1_amd64.deb
     ```
 
-# Upgrading to v1.64.0
+# Upgrading to v1.66.0
 
 ## Delegation of email validation no longer supported
 
 As of this version, Synapse no longer allows the tasks of verifying email address
 ownership, and password reset confirmation, to be delegated to an identity server.
+This removal was previously planned for Synapse 1.64.0, but was
+[delayed](https://github.com/matrix-org/synapse/issues/13421) until now to give
+homeserver administrators more notice of the change.
 
 To continue to allow users to add email addresses to their homeserver accounts,
-and perform password resets, make sure that Synapse is configured with a
-working email server in the `email` configuration section (including, at a
-minimum, a `notif_from` setting.)
+and perform password resets, make sure that Synapse is configured with a working
+email server in the [`email` configuration
+section](https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html#email)
+(including, at a minimum, a `notif_from` setting.)
 
 Specifying an `email` setting under `account_threepid_delegates` will now cause
 an error at startup.
 
+# Upgrading to v1.64.0
+
+## Deprecation of the ability to delegate e-mail verification to identity servers
+
+Synapse v1.66.0 will remove the ability to delegate the tasks of verifying email address ownership, and password reset confirmation, to an identity server.
+
+If you require your homeserver to verify e-mail addresses or to support password resets via e-mail, please configure your homeserver with SMTP access so that it can send e-mails on its own behalf.
+[Consult the configuration documentation for more information.](https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html#email)
+
+The option that will be removed is `account_threepid_delegates.email`.
+
+
 ## Changes to the event replication streams
 
 Synapse now includes a flag indicating if an event is an outlier when
@@ -114,6 +130,15 @@ vice versa.
 Once all workers are upgraded to v1.64 (or downgraded to v1.63), event
 replication will resume as normal.
 
+## frozendict release
+
+[frozendict 2.3.3](https://github.com/Marco-Sulla/python-frozendict/releases/tag/v2.3.3)
+has recently been released, which fixes a memory leak that occurs during `/sync`
+requests. We advise server administrators who installed Synapse via pip to upgrade
+frozendict with `pip install --upgrade frozendict`. The Docker image
+`matrixdotorg/synapse` and the Debian packages from `packages.matrix.org` already
+include the updated library.
+
 # Upgrading to v1.62.0
 
 ## New signatures for spam checker callbacks
diff --git a/docs/usage/administration/admin_api/README.md b/docs/usage/administration/admin_api/README.md
index c60b6da0de..f11e0b19a6 100644
--- a/docs/usage/administration/admin_api/README.md
+++ b/docs/usage/administration/admin_api/README.md
@@ -5,8 +5,9 @@
 Many of the API calls in the admin api will require an `access_token` for a
 server admin. (Note that a server admin is distinct from a room admin.)
 
-A user can be marked as a server admin by updating the database directly, e.g.:
+An existing user can be marked as a server admin by updating the database directly.
 
+Check your [database settings](config_documentation.md#database) in the configuration file, connect to the correct database using either `psql [database name]` (if using PostgreSQL) or `sqlite3 path/to/your/database.db` (if using SQLite) and elevate the user `@foo:bar.com` to administrator.
 ```sql
 UPDATE users SET admin = 1 WHERE name = '@foo:bar.com';
 ```
diff --git a/docs/usage/administration/admin_api/registration_tokens.md b/docs/usage/administration/admin_api/registration_tokens.md
index 13d5eb75e9..90cbc21125 100644
--- a/docs/usage/administration/admin_api/registration_tokens.md
+++ b/docs/usage/administration/admin_api/registration_tokens.md
@@ -2,11 +2,11 @@
 
 This API allows you to manage tokens which can be used to authenticate
 registration requests, as proposed in
-[MSC3231](https://github.com/matrix-org/matrix-doc/blob/main/proposals/3231-token-authenticated-registration.md).
+[MSC3231](https://github.com/matrix-org/matrix-doc/blob/main/proposals/3231-token-authenticated-registration.md)
+and stabilised in version 1.2 of the Matrix specification.
 To use it, you will need to enable the `registration_requires_token` config
 option, and authenticate by providing an `access_token` for a server admin:
-see [Admin API](../../usage/administration/admin_api).
-Note that this API is still experimental; not all clients may support it yet.
+see [Admin API](../admin_api).
 
 
 ## Registration token objects
diff --git a/docs/usage/administration/admin_faq.md b/docs/usage/administration/admin_faq.md
index 3dcad4bbef..7ba5a83f04 100644
--- a/docs/usage/administration/admin_faq.md
+++ b/docs/usage/administration/admin_faq.md
@@ -2,9 +2,9 @@
 
 How do I become a server admin?
 ---
-If your server already has an admin account you should use the user admin API to promote other accounts to become admins. See [User Admin API](../../admin_api/user_admin_api.md#Change-whether-a-user-is-a-server-administrator-or-not)
+If your server already has an admin account you should use the [User Admin API](../../admin_api/user_admin_api.md#Change-whether-a-user-is-a-server-administrator-or-not) to promote other accounts to become admins.
 
-If you don't have any admin accounts yet you won't be able to use the admin API so you'll have to edit the database manually. Manually editing the database is generally not recommended so once you have an admin account, use the admin APIs to make further changes.
+If you don't have any admin accounts yet you won't be able to use the admin API, so you'll have to edit the database manually. Manually editing the database is generally not recommended so once you have an admin account: use the admin APIs to make further changes.
 
 ```sql
 UPDATE users SET admin = 1 WHERE name = '@foo:bar.com';
@@ -32,9 +32,11 @@ What users are registered on my server?
 SELECT NAME from users;
 ```
 
-Manually resetting passwords:
+Manually resetting passwords
 ---
-See https://github.com/matrix-org/synapse/blob/master/README.rst#password-reset
+Users can reset their password through their client. Alternatively, a server admin
+can reset a user's password using the [admin API](../../admin_api/user_admin_api.md#reset-password).
+
 
 I have a problem with my server. Can I just delete my database and start again?
 ---
@@ -101,3 +103,83 @@ LIMIT 10;
 
 You can also use the [List Room API](../../admin_api/rooms.md#list-room-api)
 and `order_by` `state_events`.
+
+
+People can't accept room invitations from me
+---
+
+The typical failure mode here is that you send an invitation to someone
+to join a room or direct chat, but when they go to accept it, they get an
+error (typically along the lines of "Invalid signature"). They might see
+something like the following in their logs:
+
+    2019-09-11 19:32:04,271 - synapse.federation.transport.server - 288 - WARNING - GET-11752 - authenticate_request failed: 401: Invalid signature for server <server> with key ed25519:a_EqML: Unable to verify signature for <server>
+
+This is normally caused by a misconfiguration in your reverse-proxy. See [the reverse proxy docs](docs/reverse_proxy.md) and double-check that your settings are correct.
+
+
+Help!! Synapse is slow and eats all my RAM/CPU!
+-----------------------------------------------
+
+First, ensure you are running the latest version of Synapse, using Python 3
+with a [PostgreSQL database](../../postgres.md).
+
+Synapse's architecture is quite RAM hungry currently - we deliberately
+cache a lot of recent room data and metadata in RAM in order to speed up
+common requests. We'll improve this in the future, but for now the easiest
+way to either reduce the RAM usage (at the risk of slowing things down)
+is to set the almost-undocumented ``SYNAPSE_CACHE_FACTOR`` environment
+variable. The default is 0.5, which can be decreased to reduce RAM usage
+in memory constrained environments, or increased if performance starts to
+degrade.
+
+However, degraded performance due to a low cache factor, common on
+machines with slow disks, often leads to explosions in memory use due
+backlogged requests. In this case, reducing the cache factor will make
+things worse. Instead, try increasing it drastically. 2.0 is a good
+starting value.
+
+Using [libjemalloc](https://jemalloc.net) can also yield a significant
+improvement in overall memory use, and especially in terms of giving back
+RAM to the OS. To use it, the library must simply be put in the
+LD_PRELOAD environment variable when launching Synapse. On Debian, this
+can be done by installing the `libjemalloc1` package and adding this
+line to `/etc/default/matrix-synapse`:
+
+    LD_PRELOAD=/usr/lib/x86_64-linux-gnu/libjemalloc.so.1
+
+This made a significant difference on Python 2.7 - it's unclear how
+much of an improvement it provides on Python 3.x.
+
+If you're encountering high CPU use by the Synapse process itself, you
+may be affected by a bug with presence tracking that leads to a
+massive excess of outgoing federation requests (see [discussion](https://github.com/matrix-org/synapse/issues/3971)). If metrics
+indicate that your server is also issuing far more outgoing federation
+requests than can be accounted for by your users' activity, this is a
+likely cause. The misbehavior can be worked around by disabling presence
+in the Synapse config file: [see here](../configuration/config_documentation.md#presence).
+
+
+Running out of File Handles
+---------------------------
+
+If Synapse runs out of file handles, it typically fails badly - live-locking
+at 100% CPU, and/or failing to accept new TCP connections (blocking the
+connecting client).  Matrix currently can legitimately use a lot of file handles,
+thanks to busy rooms like `#matrix:matrix.org` containing hundreds of participating
+servers.  The first time a server talks in a room it will try to connect
+simultaneously to all participating servers, which could exhaust the available
+file descriptors between DNS queries & HTTPS sockets, especially if DNS is slow
+to respond. (We need to improve the routing algorithm used to be better than
+full mesh, but as of March 2019 this hasn't happened yet).
+
+If you hit this failure mode, we recommend increasing the maximum number of
+open file handles to be at least 4096 (assuming a default of 1024 or 256).
+This is typically done by editing ``/etc/security/limits.conf``
+
+Separately, Synapse may leak file handles if inbound HTTP requests get stuck
+during processing - e.g. blocked behind a lock or talking to a remote server etc.
+This is best diagnosed by matching up the 'Received request' and 'Processed request'
+log lines and looking for any 'Processed request' lines which take more than
+a few seconds to execute. Please let us know at [`#synapse:matrix.org`](https://matrix.to/#/#synapse-dev:matrix.org) if
+you see this failure mode so we can help debug it, however.
diff --git a/docs/usage/configuration/config_documentation.md b/docs/usage/configuration/config_documentation.md
index 53e077d85b..8ae018e628 100644
--- a/docs/usage/configuration/config_documentation.md
+++ b/docs/usage/configuration/config_documentation.md
@@ -1,11 +1,11 @@
 # Configuring Synapse
 
-This is intended as a guide to the Synapse configuration. The behavior of a Synapse instance can be modified 
-through the many configuration settings documented here — each config option is explained, 
+This is intended as a guide to the Synapse configuration. The behavior of a Synapse instance can be modified
+through the many configuration settings documented here — each config option is explained,
 including what the default is, how to change the default and what sort of behaviour the setting governs.
-Also included is an example configuration for each setting. If you don't want to spend a lot of time 
+Also included is an example configuration for each setting. If you don't want to spend a lot of time
 thinking about options, the config as generated sets sensible defaults for all values. Do note however that the
-database defaults to SQLite, which is not recommended for production usage. You can read more on this subject 
+database defaults to SQLite, which is not recommended for production usage. You can read more on this subject
 [here](../../setup/installation.md#using-postgresql).
 
 ## Config Conventions
@@ -26,17 +26,17 @@ messages from the database after 5 minutes, rather than 5 months.
 In addition, configuration options referring to size use the following suffixes:
 
 * `M` = MiB, or 1,048,576 bytes
-* `K` = KiB, or 1024 bytes 
+* `K` = KiB, or 1024 bytes
 
 For example, setting `max_avatar_size: 10M` means that Synapse will not accept files larger than 10,485,760 bytes
-for a user avatar. 
+for a user avatar.
 
-### YAML 
+### YAML
 The configuration file is a [YAML](https://yaml.org/) file, which means that certain syntax rules
 apply if you want your config file to be read properly. A few helpful things to know:
-* `#` before any option in the config will comment out that setting and either a default (if available) will 
+* `#` before any option in the config will comment out that setting and either a default (if available) will
    be applied or Synapse will ignore the setting. Thus, in example #1 below, the setting will be read and
-   applied, but in example #2 the setting will not be read and a default will be applied.  
+   applied, but in example #2 the setting will not be read and a default will be applied.
 
    Example #1:
    ```yaml
@@ -50,13 +50,13 @@ apply if you want your config file to be read properly. A few helpful things to
   will determine whether a given setting is read as part of another
   setting, or considered on its own. Thus, in example #1, the `enabled` setting
   is read as a sub-option of the `presence` setting, and will be properly applied.
-  
+
   However, the lack of indentation before the `enabled` setting in example #2 means
   that when reading the config, Synapse will consider both `presence` and `enabled` as
   different settings. In this case, `presence` has no value, and thus a default applied, and `enabled`
   is an option that Synapse doesn't recognize and thus ignores.
-  
-  Example #1: 
+
+  Example #1:
   ```yaml
   presence:
     enabled: false
@@ -66,54 +66,11 @@ apply if you want your config file to be read properly. A few helpful things to
   presence:
   enabled: false
   ```
-  In this manual, all top-level settings (ones with no indentation) are identified 
-  at the beginning of their section (i.e. "### `example_setting`") and 
-  the sub-options, if any, are identified and listed in the body of the section. 
+  In this manual, all top-level settings (ones with no indentation) are identified
+  at the beginning of their section (i.e. "### `example_setting`") and
+  the sub-options, if any, are identified and listed in the body of the section.
   In addition, each setting has an example of its usage, with the proper indentation
-  shown. 
-
-## Contents
-[Modules](#modules)
-
-[Server](#server)
-
-[Homeserver Blocking](#homeserver-blocking)
-
-[TLS](#tls)
-
-[Federation](#federation)
-
-[Caching](#caching)
-
-[Database](#database)
-
-[Logging](#logging)
-
-[Ratelimiting](#ratelimiting)
-
-[Media Store](#media-store)
-
-[Captcha](#captcha)
-
-[TURN](#turn)
-
-[Registration](#registration)
-
-[API Configuration](#api-configuration)
-
-[Signing Keys](#signing-keys)
-
-[Single Sign On Integration](#single-sign-on-integration)
-
-[Push](#push)
-
-[Rooms](#rooms)
-
-[Opentracing](#opentracing)
-
-[Workers](#workers)
-
-[Background Updates](#background-updates)
+  shown.
 
 ## Modules
 
@@ -126,7 +83,7 @@ documentation on how to configure or create custom modules for Synapse.
 ---
 ### `modules`
 
-Use the `module` sub-option to add modules under this option to extend functionality. 
+Use the `module` sub-option to add modules under this option to extend functionality.
 The `module` setting then has a sub-option, `config`, which can be used to define some configuration
 for the `module`.
 
@@ -166,11 +123,11 @@ The `server_name` cannot be changed later so it is important to
 configure this correctly before you start Synapse. It should be all
 lowercase and may contain an explicit port.
 
-There is no default for this option. 
- 
+There is no default for this option.
+
 Example configuration #1:
 ```yaml
-server_name: matrix.org 
+server_name: matrix.org
 ```
 Example configuration #2:
 ```yaml
@@ -188,7 +145,7 @@ pid_file: DATADIR/homeserver.pid
 ---
 ### `web_client_location`
 
-The absolute URL to the web client which `/` will redirect to. Defaults to none. 
+The absolute URL to the web client which `/` will redirect to. Defaults to none.
 
 Example configuration:
 ```yaml
@@ -217,7 +174,7 @@ By default, other servers will try to reach our server on port 8448, which can
 be inconvenient in some environments.
 
 Provided `https://<server_name>/` on port 443 is routed to Synapse, this
-option configures Synapse to serve a file at `https://<server_name>/.well-known/matrix/server`. 
+option configures Synapse to serve a file at `https://<server_name>/.well-known/matrix/server`.
 This will tell other servers to send traffic to port 443 instead.
 
 This option currently defaults to false.
@@ -235,7 +192,7 @@ serve_server_wellknown: true
 This option allows server runners to add arbitrary key-value pairs to the [client-facing `.well-known` response](https://spec.matrix.org/latest/client-server-api/#well-known-uri).
 Note that the `public_baseurl` config option must be provided for Synapse to serve a response to `/.well-known/matrix/client` at all.
 
-If this option is provided, it parses the given yaml to json and 
+If this option is provided, it parses the given yaml to json and
 serves it on `/.well-known/matrix/client` endpoint
 alongside the standard properties.
 
@@ -243,16 +200,16 @@ alongside the standard properties.
 
 Example configuration:
 ```yaml
-extra_well_known_client_content : 
+extra_well_known_client_content :
   option1: value1
   option2: value2
 ```
 ---
 ### `soft_file_limit`
- 
+
 Set the soft limit on the number of file descriptors synapse can use.
 Zero is used to indicate synapse should set the soft limit to the hard limit.
-Defaults to 0. 
+Defaults to 0.
 
 Example configuration:
 ```yaml
@@ -262,8 +219,8 @@ soft_file_limit: 3
 ### `presence`
 
 Presence tracking allows users to see the state (e.g online/offline)
-of other local and remote users. Set the `enabled` sub-option to false to  
-disable presence tracking on this homeserver. Defaults to true. 
+of other local and remote users. Set the `enabled` sub-option to false to
+disable presence tracking on this homeserver. Defaults to true.
 This option replaces the previous top-level 'use_presence' option.
 
 Example configuration:
@@ -274,8 +231,8 @@ presence:
 ---
 ### `require_auth_for_profile_requests`
 
-Whether to require authentication to retrieve profile data (avatars, display names) of other 
-users through the client API. Defaults to false. Note that profile data is also available 
+Whether to require authentication to retrieve profile data (avatars, display names) of other
+users through the client API. Defaults to false. Note that profile data is also available
 via the federation API, unless `allow_profile_lookup_over_federation` is set to false.
 
 Example configuration:
@@ -286,11 +243,11 @@ require_auth_for_profile_requests: true
 ### `limit_profile_requests_to_users_who_share_rooms`
 
 Use this option to require a user to share a room with another user in order
-to retrieve their profile information. Only checked on Client-Server 
+to retrieve their profile information. Only checked on Client-Server
 requests. Profile requests from other servers should be checked by the
 requesting server. Defaults to false.
 
-Example configuration: 
+Example configuration:
 ```yaml
 limit_profile_requests_to_users_who_share_rooms: true
 ```
@@ -336,7 +293,7 @@ The default room version for newly created rooms on this server.
 Known room versions are listed [here](https://spec.matrix.org/latest/rooms/#complete-list-of-room-versions)
 
 For example, for room version 1, `default_room_version` should be set
-to "1". 
+to "1".
 
 Currently defaults to "9".
 
@@ -348,7 +305,7 @@ default_room_version: "8"
 ### `gc_thresholds`
 
 The garbage collection threshold parameters to pass to `gc.set_threshold`, if defined.
-Defaults to none. 
+Defaults to none.
 
 Example configuration:
 ```yaml
@@ -358,7 +315,7 @@ gc_thresholds: [700, 10, 10]
 ### `gc_min_interval`
 
 The minimum time in seconds between each GC for a generation, regardless of
-the GC thresholds. This ensures that we don't do GC too frequently. A value of `[1s, 10s, 30s]` 
+the GC thresholds. This ensures that we don't do GC too frequently. A value of `[1s, 10s, 30s]`
 indicates that a second must pass between consecutive generation 0 GCs, etc.
 
 Defaults to `[1s, 10s, 30s]`.
@@ -400,7 +357,7 @@ enable_search: false
 ```
 ---
 ### `ip_range_blacklist`
- 
+
 This option prevents outgoing requests from being sent to the specified blacklisted IP address
 CIDR ranges. If this option is not specified then it defaults to private IP
 address ranges (see the example below).
@@ -463,13 +420,13 @@ configuration.
 
 Sub-options for each listener include:
 
-* `port`: the TCP port to bind to. 
+* `port`: the TCP port to bind to.
 
 * `bind_addresses`: a list of local addresses to listen on. The default is
        'all local interfaces'.
 
 * `type`: the type of listener. Normally `http`, but other valid options are:
-    
+
    * `manhole`: (see the docs [here](../../manhole.md)),
 
    * `metrics`: (see the docs [here](../../metrics-howto.md)),
@@ -486,7 +443,8 @@ Sub-options for each listener include:
 
    * `names`: a list of names of HTTP resources. See below for a list of valid resource names.
 
-   * `compress`: set to true to enable HTTP compression for this resource.
+   * `compress`: set to true to enable gzip compression on HTTP bodies for this resource. This is currently only supported with the
+     `client`, `consent`, `metrics` and `federation` resources.
 
 * `additional_resources`: Only valid for an 'http' listener. A map of
    additional endpoints which should be loaded via dynamic modules.
@@ -585,7 +543,7 @@ forward extremities reaches a given threshold, Synapse will send an
 `org.matrix.dummy_event` event, which will reduce the forward extremities
 in the room.
 
-This setting defines the threshold (i.e. number of forward extremities in the room) at which dummy events are sent. 
+This setting defines the threshold (i.e. number of forward extremities in the room) at which dummy events are sent.
 The default value is 10.
 
 Example configuration:
@@ -612,7 +570,7 @@ Useful options for Synapse admins.
 
 ### `admin_contact`
 
-How to reach the server admin, used in `ResourceLimitError`. Defaults to none. 
+How to reach the server admin, used in `ResourceLimitError`. Defaults to none.
 
 Example configuration:
 ```yaml
@@ -622,7 +580,7 @@ admin_contact: 'mailto:admin@server.com'
 ### `hs_disabled` and `hs_disabled_message`
 
 Blocks users from connecting to the homeserver and provides a human-readable reason
-why the connection was blocked. Defaults to false. 
+why the connection was blocked. Defaults to false.
 
 Example configuration:
 ```yaml
@@ -632,20 +590,20 @@ hs_disabled_message: 'Reason for why the HS is blocked'
 ---
 ### `limit_usage_by_mau`
 
-This option disables/enables monthly active user blocking. Used in cases where the admin or 
-server owner wants to limit to the number of monthly active users. When enabled and a limit is 
+This option disables/enables monthly active user blocking. Used in cases where the admin or
+server owner wants to limit to the number of monthly active users. When enabled and a limit is
 reached the server returns a `ResourceLimitError` with error type `Codes.RESOURCE_LIMIT_EXCEEDED`.
 Defaults to false. If this is enabled, a value for `max_mau_value` must also be set.
 
 Example configuration:
 ```yaml
-limit_usage_by_mau: true 
+limit_usage_by_mau: true
 ```
 ---
 ### `max_mau_value`
 
-This option sets the hard limit of monthly active users above which the server will start 
-blocking user actions if `limit_usage_by_mau` is enabled. Defaults to 0.  
+This option sets the hard limit of monthly active users above which the server will start
+blocking user actions if `limit_usage_by_mau` is enabled. Defaults to 0.
 
 Example configuration:
 ```yaml
@@ -658,7 +616,7 @@ The option `mau_trial_days` is a means to add a grace period for active users. I
 means that users must be active for the specified number of days before they
 can be considered active and guards against the case where lots of users
 sign up in a short space of time never to return after their initial
-session. Defaults to 0. 
+session. Defaults to 0.
 
 Example configuration:
 ```yaml
@@ -674,7 +632,7 @@ use the value of `mau_trial_days` instead.
 
 Example configuration:
 ```yaml
-mau_appservice_trial_days: 
+mau_appservice_trial_days:
   my_appservice_id: 3
   another_appservice_id: 6
 ```
@@ -696,7 +654,7 @@ mau_limit_alerting: false
 
 If enabled, the metrics for the number of monthly active users will
 be populated, however no one will be limited based on these numbers. If `limit_usage_by_mau`
-is true, this is implied to be true. Defaults to false. 
+is true, this is implied to be true. Defaults to false.
 
 Example configuration:
 ```yaml
@@ -720,7 +678,7 @@ mau_limit_reserved_threepids:
 ### `server_context`
 
 This option is used by phonehome stats to group together related servers.
-Defaults to none. 
+Defaults to none.
 
 Example configuration:
 ```yaml
@@ -736,11 +694,11 @@ resource-constrained. Options for this setting include:
 * `enabled`: whether this check is enabled. Defaults to false.
 * `complexity`: the limit above which rooms cannot be joined. The default is 1.0.
 * `complexity_error`: override the error which is returned when the room is too complex with a
-   custom message. 
+   custom message.
 * `admins_can_join`: allow server admins to join complex rooms. Default is false.
 
 Room complexity is an arbitrary measure based on factors such as the number of
-users in the room. 
+users in the room.
 
 Example configuration:
 ```yaml
@@ -775,7 +733,7 @@ allow_per_room_profiles: false
 ### `max_avatar_size`
 
 The largest permissible file size in bytes for a user avatar. Defaults to no restriction.
-Use M for MB and K for KB. 
+Use M for MB and K for KB.
 
 Note that user avatar changes will not work if this is set without using Synapse's media repository.
 
@@ -801,6 +759,10 @@ allowed_avatar_mimetypes: ["image/png", "image/jpeg", "image/gif"]
 How long to keep redacted events in unredacted form in the database. After
 this period redacted events get replaced with their redacted form in the DB.
 
+Synapse will check whether the rentention period has concluded for redacted
+events every 5 minutes. Thus, even if this option is set to `0`, Synapse may
+still take up to 5 minutes to purge redacted events from the database.
+
 Defaults to `7d`. Set to `null` to disable.
 
 Example configuration:
@@ -808,7 +770,7 @@ Example configuration:
 redaction_retention_period: 28d
 ```
 ---
-### `user_ips_max_age` 
+### `user_ips_max_age`
 
 How long to track users' last seen time and IPs in the database.
 
@@ -823,7 +785,7 @@ user_ips_max_age: 14d
 
 Inhibits the `/requestToken` endpoints from returning an error that might leak
 information about whether an e-mail address is in use or not on this
-homeserver. Defaults to false. 
+homeserver. Defaults to false.
 Note that for some endpoints the error situation is the e-mail already being
 used, and for others the error is entering the e-mail being unused.
 If this option is enabled, instead of returning an error, these endpoints will
@@ -859,9 +821,9 @@ next_link_domain_whitelist: ["matrix.org"]
 ### `templates` and `custom_template_directory`
 
 These options define templates to use when generating email or HTML page contents.
-The `custom_template_directory` determines which directory Synapse will try to 
+The `custom_template_directory` determines which directory Synapse will try to
 find template files in to use to generate email or HTML page contents.
-If not set, or a file is not found within the template directory, a default 
+If not set, or a file is not found within the template directory, a default
 template from within the Synapse package will be used.
 
 See [here](../../templates.md) for more
@@ -884,26 +846,30 @@ the `allowed_lifetime_min` and `allowed_lifetime_max` config options.
 
 If this feature is enabled, Synapse will regularly look for and purge events
 which are older than the room's maximum retention period. Synapse will also
-filter events received over federation so that events that should have been 
-purged are ignored and not stored again. 
+filter events received over federation so that events that should have been
+purged are ignored and not stored again.
 
-The message retention policies feature is disabled by default.
+The message retention policies feature is disabled by default. Please be advised 
+that enabling this feature carries some risk. There are known bugs with the implementation
+which can cause database corruption. Setting retention to delete older history
+is less risky than deleting newer history but in general caution is advised when enabling this
+experimental feature. You can read more about this feature [here](../../message_retention_policies.md).
 
 This setting has the following sub-options:
 * `default_policy`: Default retention policy. If set, Synapse will apply it to rooms that lack the
-   'm.room.retention' state event. This option is further specified by the 
-   `min_lifetime` and `max_lifetime` sub-options associated with it. Note that the 
-    value of `min_lifetime` doesn't matter much because Synapse doesn't take it into account yet. 
+   'm.room.retention' state event. This option is further specified by the
+   `min_lifetime` and `max_lifetime` sub-options associated with it. Note that the
+    value of `min_lifetime` doesn't matter much because Synapse doesn't take it into account yet.
 
-* `allowed_lifetime_min` and `allowed_lifetime_max`: Retention policy limits. If 
-   set, and the state of a room contains a `m.room.retention` event in its state 
+* `allowed_lifetime_min` and `allowed_lifetime_max`: Retention policy limits. If
+   set, and the state of a room contains a `m.room.retention` event in its state
    which contains a `min_lifetime` or a `max_lifetime` that's out of these bounds,
    Synapse will cap the room's policy to these limits when running purge jobs.
 
 * `purge_jobs` and the associated `shortest_max_lifetime` and `longest_max_lifetime` sub-options:
    Server admins can define the settings of the background jobs purging the
    events whose lifetime has expired under the `purge_jobs` section.
-   
+
   If no configuration is provided for this option, a single job will be set up to delete
   expired events in every room daily.
 
@@ -915,7 +881,7 @@ This setting has the following sub-options:
   range are optional, e.g. a job with no `shortest_max_lifetime` and a
   `longest_max_lifetime` of '3d' will handle every room with a retention policy
   whose `max_lifetime` is lower than or equal to three days.
-  
+
   The rationale for this per-job configuration is that some rooms might have a
   retention policy with a low `max_lifetime`, where history needs to be purged
   of outdated messages on a more frequent basis than for the rest of the rooms
@@ -944,7 +910,7 @@ retention:
     - longest_max_lifetime: 3d
       interval: 12h
     - shortest_max_lifetime: 3d
-      interval: 1d  
+      interval: 1d
 ```
 ---
 ## TLS ##
@@ -956,11 +922,11 @@ Options related to TLS.
 
 This option specifies a PEM-encoded X509 certificate for TLS.
 This certificate, as of Synapse 1.0, will need to be a valid and verifiable
-certificate, signed by a recognised Certificate Authority. Defaults to none. 
+certificate, signed by a recognised Certificate Authority. Defaults to none.
 
 Be sure to use a `.pem` file that includes the full certificate chain including
 any intermediate certificates (for instance, if using certbot, use
-`fullchain.pem` as your certificate, not `cert.pem`). 
+`fullchain.pem` as your certificate, not `cert.pem`).
 
 Example configuration:
 ```yaml
@@ -969,7 +935,7 @@ tls_certificate_path: "CONFDIR/SERVERNAME.tls.crt"
 ---
 ### `tls_private_key_path`
 
-PEM-encoded private key for TLS. Defaults to none. 
+PEM-encoded private key for TLS. Defaults to none.
 
 Example configuration:
 ```yaml
@@ -1098,26 +1064,26 @@ allow_device_name_lookup_over_federation: true
 ---
 ## Caching ##
 
-Options related to caching
+Options related to caching.
 
 ---
 ### `event_cache_size`
 
 The number of events to cache in memory. Not affected by
-`caches.global_factor`. Defaults to 10K.
+`caches.global_factor` and is not part of the `caches` section. Defaults to 10K.
 
 Example configuration:
 ```yaml
 event_cache_size: 15K
 ```
 ---
-### `cache` and associated values
+### `caches` and associated values
 
 A cache 'factor' is a multiplier that can be applied to each of
 Synapse's caches in order to increase or decrease the maximum
 number of entries that can be stored.
 
-Caching can be configured through the following sub-options:
+`caches` can be configured through the following sub-options:
 
 * `global_factor`: Controls the global cache factor, which is the default cache factor
   for all caches if a specific factor for that cache is not otherwise
@@ -1126,31 +1092,31 @@ Caching can be configured through the following sub-options:
   This can also be set by the `SYNAPSE_CACHE_FACTOR` environment
   variable. Setting by environment variable takes priority over
   setting through the config file.
-  
+
   Defaults to 0.5, which will halve the size of all caches.
 
 * `per_cache_factors`: A dictionary of cache name to cache factor for that individual
    cache. Overrides the global cache factor for a given cache.
-  
+
    These can also be set through environment variables comprised
    of `SYNAPSE_CACHE_FACTOR_` + the name of the cache in capital
    letters and underscores. Setting by environment variable
    takes priority over setting through the config file.
    Ex. `SYNAPSE_CACHE_FACTOR_GET_USERS_WHO_SHARE_ROOM_WITH_USER=2.0`
-  
+
    Some caches have '*' and other characters that are not
    alphanumeric or underscores. These caches can be named with or
    without the special characters stripped. For example, to specify
    the cache factor for `*stateGroupCache*` via an environment
    variable would be `SYNAPSE_CACHE_FACTOR_STATEGROUPCACHE=2.0`.
- 
+
 * `expire_caches`: Controls whether cache entries are evicted after a specified time
    period. Defaults to true. Set to false to disable this feature. Note that never expiring
-   caches may result in excessive memory usage. 
+   caches may result in excessive memory usage.
 
 * `cache_entry_ttl`: If `expire_caches` is enabled, this flag controls how long an entry can
   be in a cache without having been accessed before being evicted.
-  Defaults to 30m. 
+  Defaults to 30m.
 
 * `sync_response_cache_duration`: Controls how long the results of a /sync request are
   cached for after a successful response is returned. A higher duration can help clients
@@ -1161,8 +1127,8 @@ Caching can be configured through the following sub-options:
   *Changed in Synapse 1.62.0*: The default was changed from 0 to 2m.
 
 * `cache_autotuning` and its sub-options `max_cache_memory_usage`, `target_cache_memory_usage`, and
-   `min_cache_ttl` work in conjunction with each other to maintain a balance between cache memory 
-   usage and cache entry availability. You must be using [jemalloc](https://github.com/matrix-org/synapse#help-synapse-is-slow-and-eats-all-my-ramcpu) 
+   `min_cache_ttl` work in conjunction with each other to maintain a balance between cache memory
+   usage and cache entry availability. You must be using [jemalloc](https://github.com/matrix-org/synapse#help-synapse-is-slow-and-eats-all-my-ramcpu)
    to utilize this option, and all three of the options must be specified for this feature to work. This option
    defaults to off, enable it by providing values for the sub-options listed below. Please note that the feature will not work
    and may cause unstable behavior (such as excessive emptying of caches or exceptions) if all of the values are not provided.
@@ -1175,10 +1141,11 @@ Caching can be configured through the following sub-options:
         for this option.
      * `min_cache_ttl` sets a limit under which newer cache entries are not evicted and is only applied when
         caches are actively being evicted/`max_cache_memory_usage` has been exceeded. This is to protect hot caches
-        from being emptied while Synapse is evicting due to memory. There is no default value for this option. 
+        from being emptied while Synapse is evicting due to memory. There is no default value for this option.
 
 Example configuration:
 ```yaml
+event_cache_size: 15K
 caches:
   global_factor: 1.0
   per_cache_factors:
@@ -1199,7 +1166,7 @@ The cache factors (i.e. `caches.global_factor` and `caches.per_cache_factors`)
 kill -HUP [PID_OF_SYNAPSE_PROCESS]
 ```
 
-If you are running multiple workers, you must individually update the worker 
+If you are running multiple workers, you must individually update the worker
 config file and send this signal to each worker process.
 
 If you're using the [example systemd service](https://github.com/matrix-org/synapse/blob/develop/contrib/systemd/matrix-synapse.service)
@@ -1219,7 +1186,7 @@ its data.
 Associated sub-options:
 
 * `name`: this option specifies the database engine to use: either `sqlite3` (for SQLite)
-  or `psycopg2` (for PostgreSQL). If no name is specified Synapse will default to SQLite. 
+  or `psycopg2` (for PostgreSQL). If no name is specified Synapse will default to SQLite.
 
 * `txn_limit` gives the maximum number of transactions to run per connection
   before reconnecting. Defaults to 0, which means no limit.
@@ -1355,7 +1322,7 @@ databases:
 ```
 ---
 ## Logging ##
-Config options related to logging. 
+Config options related to logging.
 
 ---
 ### `log_config`
@@ -1368,7 +1335,7 @@ log_config: "CONFDIR/SERVERNAME.log.config"
 ```
 ---
 ## Ratelimiting ##
-Options related to ratelimiting in Synapse. 
+Options related to ratelimiting in Synapse.
 
 Each ratelimiting configuration is made of two parameters:
    - `per_second`: number of requests a client can send per second.
@@ -1378,7 +1345,7 @@ Each ratelimiting configuration is made of two parameters:
 
 
 Ratelimiting settings for client messaging.
-   
+
 This is a ratelimiting option for messages that ratelimits sending based on the account the client
 is using. It defaults to: `per_second: 0.2`, `burst_count: 10`.
 
@@ -1392,7 +1359,7 @@ rc_message:
 ### `rc_registration`
 
 This option ratelimits registration requests based on the client's IP address.
-It defaults to `per_second: 0.17`, `burst_count: 3`. 
+It defaults to `per_second: 0.17`, `burst_count: 3`.
 
 Example configuration:
 ```yaml
@@ -1403,7 +1370,7 @@ rc_registration:
 ---
 ### `rc_registration_token_validity`
 
-This option checks the validity of registration tokens that ratelimits requests based on 
+This option checks the validity of registration tokens that ratelimits requests based on
 the client's IP address.
 Defaults to `per_second: 0.1`, `burst_count: 5`.
 
@@ -1412,18 +1379,18 @@ Example configuration:
 rc_registration_token_validity:
   per_second: 0.3
   burst_count: 6
-```   
+```
 ---
 ### `rc_login`
 
 This option specifies several limits for login:
 * `address` ratelimits login requests based on the client's IP
       address. Defaults to `per_second: 0.17`, `burst_count: 3`.
-    
+
 * `account` ratelimits login requests based on the account the
   client is attempting to log into. Defaults to `per_second: 0.17`,
   `burst_count: 3`.
-    
+
 * `failted_attempts` ratelimits login requests based on the account the
   client is attempting to log into, based on the amount of failed login
   attempts for this account. Defaults to `per_second: 0.17`, `burst_count: 3`.
@@ -1444,9 +1411,9 @@ rc_login:
 ---
 ### `rc_admin_redaction`
 
-This option sets ratelimiting redactions by room admins. If this is not explicitly 
+This option sets ratelimiting redactions by room admins. If this is not explicitly
 set then it uses the same ratelimiting as per `rc_message`. This is useful
-to allow room admins to deal with abuse quickly. 
+to allow room admins to deal with abuse quickly.
 
 Example configuration:
 ```yaml
@@ -1459,12 +1426,12 @@ rc_admin_redaction:
 
 This option allows for ratelimiting number of rooms a user can join. This setting has the following sub-options:
 
-* `local`: ratelimits when users are joining rooms the server is already in. 
+* `local`: ratelimits when users are joining rooms the server is already in.
    Defaults to `per_second: 0.1`, `burst_count: 10`.
 
 * `remote`: ratelimits when users are trying to join rooms not on the server (which
   can be more computationally expensive than restricting locally). Defaults to
-  `per_second: 0.01`, `burst_count: 10` 
+  `per_second: 0.01`, `burst_count: 10`
 
 Example configuration:
 ```yaml
@@ -1510,9 +1477,9 @@ rc_3pid_validation:
 ---
 ### `rc_invites`
 
-This option sets ratelimiting how often invites can be sent in a room or to a 
+This option sets ratelimiting how often invites can be sent in a room or to a
 specific user. `per_room` defaults to `per_second: 0.3`, `burst_count: 10` and
-`per_user` defaults to `per_second: 0.003`, `burst_count: 5`. 
+`per_user` defaults to `per_second: 0.003`, `burst_count: 5`.
 
 Client requests that invite user(s) when [creating a
 room](https://spec.matrix.org/v1.2/client-server-api/#post_matrixclientv3createroom)
@@ -1528,6 +1495,10 @@ The `rc_invites.per_user` limit applies to the *receiver* of the invite, rather
 sender, meaning that a `rc_invite.per_user.burst_count` of 5 mandates that a single user
 cannot *receive* more than a burst of 5 invites at a time.
 
+In contrast, the `rc_invites.per_issuer` limit applies to the *issuer* of the invite, meaning that a `rc_invite.per_issuer.burst_count` of 5 mandates that single user cannot *send* more than a burst of 5 invites at a time.
+
+_Changed in version 1.63:_ added the `per_issuer` limit.
+
 Example configuration:
 ```yaml
 rc_invites:
@@ -1537,7 +1508,11 @@ rc_invites:
   per_user:
     per_second: 0.004
     burst_count: 3
+  per_issuer:
+    per_second: 0.5
+    burst_count: 5
 ```
+
 ---
 ### `rc_third_party_invite`
 
@@ -1554,7 +1529,7 @@ rc_third_party_invite:
 ---
 ### `rc_federation`
 
-Defines limits on federation requests. 
+Defines limits on federation requests.
 
 The `rc_federation` configuration has the following sub-options:
 * `window_size`: window size in milliseconds. Defaults to 1000.
@@ -1583,7 +1558,7 @@ Sets outgoing federation transaction frequency for sending read-receipts,
 per-room.
 
 If we end up trying to send out more read-receipts, they will get buffered up
-into fewer transactions. Defaults to 50. 
+into fewer transactions. Defaults to 50.
 
 Example configuration:
 ```yaml
@@ -1594,9 +1569,9 @@ federation_rr_transactions_per_room_per_second: 40
 Config options related to Synapse's media store.
 
 ---
-### `enable_media_repo` 
+### `enable_media_repo`
 
-Enable the media store service in the Synapse master. Defaults to true. 
+Enable the media store service in the Synapse master. Defaults to true.
 Set to false if you are using a separate media store worker.
 
 Example configuration:
@@ -1621,7 +1596,7 @@ locations. Defaults to none. Associated sub-options are:
 * `store_local`: whether to store newly uploaded local files
 * `store_remote`: whether to store newly downloaded local files
 * `store_synchronous`: whether to wait for successful storage for local uploads
-* `config`: sets a path to the resource through the `directory` option 
+* `config`: sets a path to the resource through the `directory` option
 
 Example configuration:
 ```yaml
@@ -1640,7 +1615,7 @@ The largest allowed upload size in bytes.
 
 If you are using a reverse proxy you may also need to set this value in
 your reverse proxy's config. Defaults to 50M. Notably Nginx has a small max body size by default.
-See [here](../../reverse_proxy.md) for more on using a reverse proxy with Synapse. 
+See [here](../../reverse_proxy.md) for more on using a reverse proxy with Synapse.
 
 Example configuration:
 ```yaml
@@ -1662,14 +1637,14 @@ Whether to generate new thumbnails on the fly to precisely match
 the resolution requested by the client. If true then whenever
 a new resolution is requested by the client the server will
 generate a new thumbnail. If false the server will pick a thumbnail
-from a precalculated list. Defaults to false. 
+from a precalculated list. Defaults to false.
 
 Example configuration:
 ```yaml
 dynamic_thumbnails: true
 ```
 ---
-### `thumbnail_sizes`  
+### `thumbnail_sizes`
 
 List of thumbnails to precalculate when an image is uploaded. Associated sub-options are:
 * `width`
@@ -1787,7 +1762,7 @@ This option sets a list of IP address CIDR ranges that the URL preview spider is
 to access even if they are specified in `url_preview_ip_range_blacklist`.
 This is useful for specifying exceptions to wide-ranging blacklisted
 target IP ranges - e.g. for enabling URL previews for a specific private
-website only visible in your network. Defaults to none. 
+website only visible in your network. Defaults to none.
 
 Example configuration:
 ```yaml
@@ -1805,7 +1780,7 @@ This is more useful if you know there is an entire shape of URL that
 you know that will never want synapse to try to spider.
 
 Each list entry is a dictionary of url component attributes as returned
-by urlparse.urlsplit as applied to the absolute form of the URL.  See 
+by urlparse.urlsplit as applied to the absolute form of the URL.  See
 [here](https://docs.python.org/2/library/urlparse.html#urlparse.urlsplit) for more
 information. Some examples are:
 
@@ -1850,7 +1825,7 @@ Example configuration:
 max_spider_size: 8M
 ```
 ---
-### `url_preview_language`
+### `url_preview_accept_language`
 
 A list of values for the Accept-Language HTTP header used when
 downloading webpages during URL preview generation. This allows
@@ -1880,8 +1855,8 @@ Example configuration:
 oEmbed allows for easier embedding content from a website. It can be
 used for generating URLs previews of services which support it. A default list of oEmbed providers
 is included with Synapse. Set `disable_default_providers` to true to disable using
-these default oEmbed URLs. Use `additional_providers` to specify additional files with oEmbed configuration (each 
-should be in the form of providers.json). By default this list is empty. 
+these default oEmbed URLs. Use `additional_providers` to specify additional files with oEmbed configuration (each
+should be in the form of providers.json). By default this list is empty.
 
 Example configuration:
 ```yaml
@@ -1898,7 +1873,7 @@ See [here](../../CAPTCHA_SETUP.md) for full details on setting up captcha.
 ---
 ### `recaptcha_public_key`
 
-This homeserver's ReCAPTCHA public key. Must be specified if `enable_registration_captcha` is 
+This homeserver's ReCAPTCHA public key. Must be specified if `enable_registration_captcha` is
 enabled.
 
 Example configuration:
@@ -1906,9 +1881,9 @@ Example configuration:
 recaptcha_public_key: "YOUR_PUBLIC_KEY"
 ```
 ---
-### `recaptcha_private_key` 
+### `recaptcha_private_key`
 
-This homeserver's ReCAPTCHA private key. Must be specified if `enable_registration_captcha` is 
+This homeserver's ReCAPTCHA private key. Must be specified if `enable_registration_captcha` is
 enabled.
 
 Example configuration:
@@ -1919,7 +1894,7 @@ recaptcha_private_key: "YOUR_PRIVATE_KEY"
 ### `enable_registration_captcha`
 
 Set to true to enable ReCaptcha checks when registering, preventing signup
-unless a captcha is answered. Requires a valid ReCaptcha public/private key. 
+unless a captcha is answered. Requires a valid ReCaptcha public/private key.
 Defaults to false.
 
 Example configuration:
@@ -1997,7 +1972,7 @@ Registration can be rate-limited using the parameters in the [Ratelimiting](#rat
 ### `enable_registration`
 
 Enable registration for new users. Defaults to false. It is highly recommended that if you enable registration,
-you use either captcha, email, or token-based verification to verify that new users are not bots. In order to enable registration 
+you use either captcha, email, or token-based verification to verify that new users are not bots. In order to enable registration
 without any verification, you must also set `enable_registration_without_verification` to true.
 
 Example configuration:
@@ -2021,7 +1996,7 @@ Time that a user's session remains valid for, after they log in.
 
 Note that this is not currently compatible with guest logins.
 
-Note also that this is calculated at login time: changes are not applied retrospectively to users who have already 
+Note also that this is calculated at login time: changes are not applied retrospectively to users who have already
 logged in.
 
 By default, this is infinite.
@@ -2039,7 +2014,7 @@ For more information about refresh tokens, please see the [manual](user_authenti
 
 Note that this only applies to clients which advertise support for refresh tokens.
 
-Note also that this is calculated at login time and refresh time: changes are not applied to 
+Note also that this is calculated at login time and refresh time: changes are not applied to
 existing sessions until they are refreshed.
 
 By default, this is 5 minutes.
@@ -2137,7 +2112,7 @@ Require users to submit a token during registration.
 Tokens can be managed using the admin [API](../administration/admin_api/registration_tokens.md).
 Note that `enable_registration` must be set to true.
 Disabling this option will not delete any tokens previously generated.
-Defaults to false. Set to true to enable.  
+Defaults to false. Set to true to enable.
 
 Example configuration:
 ```yaml
@@ -2207,7 +2182,10 @@ their account.
 by the Matrix Identity Service API
 [specification](https://matrix.org/docs/spec/identity_service/latest).)
 
-*Updated in Synapse 1.64.0*: No longer accepts an `email` option.
+*Deprecated in Synapse 1.64.0*: The `email` option is deprecated.
+
+*Removed in Synapse 1.66.0*: The `email` option has been removed.
+If present, Synapse will report a configuration error on startup.
 
 Example configuration:
 ```yaml
@@ -2262,7 +2240,7 @@ By default, any room aliases included in this list will be created
 as a publicly joinable room when the first user registers for the
 homeserver. If the room already exists, make certain it is a publicly joinable
 room, i.e. the join rule of the room must be set to 'public'. You can find more options
-relating to auto-joining rooms below. 
+relating to auto-joining rooms below.
 
 Example configuration:
 ```yaml
@@ -2316,9 +2294,9 @@ effect if `autocreate_auto_join_rooms` is true.
 Possible values for this option are:
 * "public_chat": the room is joinable by anyone, including
   federated servers if `autocreate_auto_join_rooms_federated` is true (the default).
-* "private_chat": an invitation is required to join these rooms. 
+* "private_chat": an invitation is required to join these rooms.
 * "trusted_private_chat": an invitation is required to join this room and the invitee is
-  assigned a power level of 100 upon joining the room. 
+  assigned a power level of 100 upon joining the room.
 
 If a value of "private_chat" or "trusted_private_chat" is used then
 `auto_join_mxid_localpart` must also be configured.
@@ -2355,7 +2333,7 @@ auto_join_mxid_localpart: system
 ```
 ---
 ### `auto_join_rooms_for_guests`
- 
+
 When `auto_join_rooms` is specified, setting this flag to false prevents
 guest accounts from being automatically joined to the rooms.
 
@@ -2367,7 +2345,7 @@ auto_join_rooms_for_guests: false
 ```
 ---
 ### `inhibit_user_in_use_error`
- 
+
 Whether to inhibit errors raised when registering a new account if the user ID
 already exists. If turned on, requests to `/register/available` will always
 show a user ID as available, and Synapse won't raise an error when starting
@@ -2387,7 +2365,7 @@ Config options related to metrics.
 ---
 ### `enable_metrics`
 
-Set to true to enable collection and rendering of performance metrics. 
+Set to true to enable collection and rendering of performance metrics.
 Defaults to false.
 
 Example configuration:
@@ -2398,11 +2376,11 @@ enable_metrics: true
 ### `sentry`
 
 Use this option to enable sentry integration. Provide the DSN assigned to you by sentry
-with the `dsn` setting. 
+with the `dsn` setting.
 
 NOTE: While attempts are made to ensure that the logs don't contain
 any sensitive information, this cannot be guaranteed. By enabling
-this option the sentry server may therefore receive sensitive 
+this option the sentry server may therefore receive sensitive
 information, and it in turn may then disseminate sensitive information
 through insecure notification channels if so configured.
 
@@ -2416,7 +2394,7 @@ sentry:
 
 Flags to enable Prometheus metrics which are not suitable to be
 enabled by default, either for performance reasons or limited use.
-Currently the only option is `known_servers`, which publishes 
+Currently the only option is `known_servers`, which publishes
 `synapse_federation_known_servers`, a gauge of the number of
 servers this homeserver knows about, including itself. May cause
 performance problems on large homeservers.
@@ -2460,7 +2438,7 @@ Config settings related to the client/server API
 ### `room_prejoin_state:`
 
 Controls for the state that is shared with users who receive an invite
-to a room. By default, the following state event types are shared with users who 
+to a room. By default, the following state event types are shared with users who
 receive invites to the room:
 - m.room.join_rules
 - m.room.canonical_alias
@@ -2471,7 +2449,7 @@ receive invites to the room:
 - m.room.topic
 
 To change the default behavior, use the following sub-options:
-* `disable_default_event_types`: set to true to disable the above defaults. If this 
+* `disable_default_event_types`: set to true to disable the above defaults. If this
    is enabled, only the event types listed in `additional_event_types` are shared.
    Defaults to false.
 * `additional_event_types`: Additional state event types to share with users when they are invited
@@ -2529,9 +2507,13 @@ track_appservice_user_ips: true
 ---
 ### `macaroon_secret_key`
 
-A secret which is used to sign access tokens. If none is specified,
-the `registration_shared_secret` is used, if one is given; otherwise,
-a secret key is derived from the signing key.
+A secret which is used to sign
+- access token for guest users,
+- short-term login token used during SSO logins (OIDC or SAML2) and
+- token used for unsubscribing from email notifications.
+
+If none is specified, the `registration_shared_secret` is used, if one is given;
+otherwise, a secret key is derived from the signing key.
 
 Example configuration:
 ```yaml
@@ -2561,7 +2543,7 @@ Example configuration:
 ```yaml
 signing_key_path: "CONFDIR/SERVERNAME.signing.key"
 ```
---- 
+---
 ### `old_signing_keys`
 
 The keys that the server used to sign messages with but won't use
@@ -2613,7 +2595,7 @@ Options for each entry in the list include:
    If specified, we will check that the response is signed by at least
    one of the given keys.
 * `accept_keys_insecurely`: a boolean. Normally, if `verify_keys` is unset,
-   and `federation_verify_certificates` is not `true`, synapse will refuse 
+   and `federation_verify_certificates` is not `true`, synapse will refuse
    to start, because this would allow anyone who can spoof DNS responses
    to masquerade as the trusted key server. If you know what you are doing
    and are sure that your network environment provides a secure connection
@@ -2691,15 +2673,15 @@ This setting has the following sub-options:
    * `service`: By default, the user has to go to our login page first. If you'd like
      to allow IdP-initiated login, set `allow_unsolicited` to true under `sp` in the `service`
      section.
-* `config_path`: specify a separate pysaml2 configuration file thusly: 
+* `config_path`: specify a separate pysaml2 configuration file thusly:
   `config_path: "CONFDIR/sp_conf.py"`
 * `saml_session_lifetime`: The lifetime of a SAML session. This defines how long a user has to
    complete the authentication process, if `allow_unsolicited` is unset. The default is 15 minutes.
-* `user_mapping_provider`: Using this option, an external module can be provided as a 
-   custom solution to mapping attributes returned from a saml provider onto a matrix user. The 
+* `user_mapping_provider`: Using this option, an external module can be provided as a
+   custom solution to mapping attributes returned from a saml provider onto a matrix user. The
    `user_mapping_provider` has the following attributes:
-  * `module`: The custom module's class. 
-  * `config`: Custom configuration values for the module. Use the values provided in the 
+  * `module`: The custom module's class.
+  * `config`: Custom configuration values for the module. Use the values provided in the
      example if you are using the built-in user_mapping_provider, or provide your own
      config values for a custom class if you are using one. This section will be passed as a Python
      dictionary to the module's `parse_config` method. The built-in provider takes the following two
@@ -2716,7 +2698,7 @@ This setting has the following sub-options:
    MXID was always calculated dynamically rather than stored in a table. For backwards- compatibility, we will look for `user_ids`
    matching such a pattern before creating a new account. This setting controls the SAML attribute which will be used for this
    backwards-compatibility lookup. Typically it should be 'uid', but if the attribute maps are changed, it may be necessary to change it.
-   The default is 'uid'. 
+   The default is 'uid'.
 * `attribute_requirements`: It is possible to configure Synapse to only allow logins if SAML attributes
     match particular values. The requirements can be listed under
    `attribute_requirements` as shown in the example. All of the listed attributes must
@@ -2724,7 +2706,7 @@ This setting has the following sub-options:
 * `idp_entityid`: If the metadata XML contains multiple IdP entities then the `idp_entityid`
    option must be set to the entity to redirect users to.
    Most deployments only have a single IdP entity and so should omit this option.
-  
+
 
 Once SAML support is enabled, a metadata file will be exposed at
 `https://<server>:<port>/_synapse/client/saml2/metadata.xml`, which you may be able to
@@ -2785,16 +2767,16 @@ saml2_config:
         sur_name: "the Sysadmin"
         email_address": ["admin@example.com"]
         contact_type": technical
-        
+
   saml_session_lifetime: 5m
-  
+
   user_mapping_provider:
-    # Below options are intended for the built-in provider, they should be 
-    # changed if using a custom module. 
+    # Below options are intended for the built-in provider, they should be
+    # changed if using a custom module.
     config:
       mxid_source_attribute: displayName
       mxid_mapping: dotreplace
-  
+
   grandfathered_mxid_source_attribute: upn
 
   attribute_requirements:
@@ -2922,7 +2904,7 @@ Options for each entry include:
 
        * `localpart_template`: Jinja2 template for the localpart of the MXID.
           If this is not set, the user will be prompted to choose their
-          own username (see the documentation for the `sso_auth_account_details.html` 
+          own username (see the documentation for the `sso_auth_account_details.html`
           template). This template can use the `localpart_from_email` filter.
 
        * `confirm_localpart`: Whether to prompt the user to validate (or
@@ -2935,7 +2917,7 @@ Options for each entry include:
 
        * `email_template`: Jinja2 template for the email address of the user.
           If unset, no email address will be added to the account.
-                 
+
        * `extra_attributes`: a map of Jinja2 templates for extra attributes
           to send back to the client during login. Note that these are non-standard and clients will ignore them
           without modifications.
@@ -2945,7 +2927,7 @@ Options for each entry include:
      in the ID Token.
 
 
-It is possible to configure Synapse to only allow logins if certain attributes 
+It is possible to configure Synapse to only allow logins if certain attributes
 match particular values in the OIDC userinfo. The requirements can be listed under
 `attribute_requirements` as shown here:
 ```yaml
@@ -2960,7 +2942,7 @@ userinfo by expanding the `scopes` section of the OIDC config to retrieve
 additional information from the OIDC provider.
 
 If the OIDC claim is a list, then the attribute must match any value in the list.
-Otherwise, it must exactly match the value of the claim. Using the example 
+Otherwise, it must exactly match the value of the claim. Using the example
 above, the `family_name` claim MUST be "Stephensson", but the `groups`
 claim MUST contain "admin".
 
@@ -3025,7 +3007,7 @@ cas_config:
 Additional settings to use with single-sign on systems such as OpenID Connect,
 SAML2 and CAS.
 
-Server admins can configure custom templates for pages related to SSO. See 
+Server admins can configure custom templates for pages related to SSO. See
 [here](../../templates.md) for more information.
 
 Options include:
@@ -3041,7 +3023,7 @@ Options include:
    required login flows) is whitelisted in addition to any URLs in this list.
    By default, this list contains only the login fallback page.
 * `update_profile_information`: Use this setting to keep a user's profile fields in sync with information from
-   the identity provider. Currently only syncing the displayname is supported. Fields 
+   the identity provider. Currently only syncing the displayname is supported. Fields
    are checked on every SSO login, and are updated if necessary.
    Note that enabling this option will override user profile information,
    regardless of whether users have opted-out of syncing that
@@ -3085,7 +3067,7 @@ Additional sub-options for this setting include:
    Required if `enabled` is set to true.
 * `subject_claim`: Name of the claim containing a unique identifier for the user.
    Optional, defaults to `sub`.
-* `issuer`: The issuer to validate the "iss" claim against. Optional. If provided the 
+* `issuer`: The issuer to validate the "iss" claim against. Optional. If provided the
    "iss" claim will be required and validated for all JSON web tokens.
 * `audiences`: A list of audiences to validate the "aud" claim against. Optional.
    If provided the "aud" claim will be required and validated for all JSON web tokens.
@@ -3095,7 +3077,7 @@ Additional sub-options for this setting include:
 Example configuration:
 ```yaml
 jwt_config:
-    enabled: true 
+    enabled: true
     secret: "provided-by-your-issuer"
     algorithm: "provided-by-your-issuer"
     subject_claim: "name_of_claim"
@@ -3106,7 +3088,7 @@ jwt_config:
 ---
 ### `password_config`
 
-Use this setting to enable password-based logins. 
+Use this setting to enable password-based logins.
 
 This setting has the following sub-options:
 * `enabled`: Defaults to true.
@@ -3115,10 +3097,10 @@ This setting has the following sub-options:
    to log in and reauthenticate, whilst preventing new users from setting passwords.
 * `localdb_enabled`: Set to false to disable authentication against the local password
    database. This is ignored if `enabled` is false, and is only useful
-   if you have other `password_providers`. Defaults to true. 
+   if you have other `password_providers`. Defaults to true.
 * `pepper`: Set the value here to a secret random string for extra security.
    DO NOT CHANGE THIS AFTER INITIAL SETUP!
-* `policy`: Define and enforce a password policy, such as minimum lengths for passwords, etc. 
+* `policy`: Define and enforce a password policy, such as minimum lengths for passwords, etc.
    Each parameter is optional. This is an implementation of MSC2000. Parameters are as follows:
    * `enabled`: Defaults to false. Set to true to enable.
    * `minimum_length`: Minimum accepted length for a password. Defaults to 0.
@@ -3130,7 +3112,7 @@ This setting has the following sub-options:
       Defaults to false.
    * `require_uppercase`: Whether a password must contain at least one uppercase letter.
       Defaults to false.
-      
+
 
 Example configuration:
 ```yaml
@@ -3152,7 +3134,7 @@ password_config:
 
 The amount of time to allow a user-interactive authentication session to be active.
 
-This defaults to 0, meaning the user is queried for their credentials 
+This defaults to 0, meaning the user is queried for their credentials
 before every action, but this can be overridden to allow a single
 validation to be re-used.  This weakens the protections afforded by
 the user-interactive authentication process, by allowing for multiple
@@ -3179,9 +3161,17 @@ Server admins can configure custom templates for email content. See
 
 This setting has the following sub-options:
 * `smtp_host`: The hostname of the outgoing SMTP server to use. Defaults to 'localhost'.
-* `smtp_port`: The port on the mail server for outgoing SMTP. Defaults to 25.
+* `smtp_port`: The port on the mail server for outgoing SMTP. Defaults to 465 if `force_tls` is true, else 25.
+
+  _Changed in Synapse 1.64.0:_ the default port is now aware of `force_tls`.
 * `smtp_user` and `smtp_pass`: Username/password for authentication to the SMTP server. By default, no
    authentication is attempted.
+* `force_tls`: By default, Synapse connects over plain text and then optionally upgrades
+   to TLS via STARTTLS. If this option is set to true, TLS is used from the start (Implicit TLS),
+   and the option `require_transport_security` is ignored.
+   It is recommended to enable this if supported by your mail server.
+
+  _New in Synapse 1.64.0._
 * `require_transport_security`: Set to true to require TLS transport security for SMTP.
    By default, Synapse will connect over plain text, and will then switch to
    TLS via STARTTLS *if the SMTP server supports it*. If this option is set,
@@ -3215,8 +3205,8 @@ This setting has the following sub-options:
    message(s) have been sent to, e.g. "My super room". In addition, emails related to account administration will
    can use the '%(server_name)s' placeholder, which will be replaced by the value of the
    `server_name` setting in your Synapse configuration.
-   
-   Here is a list of subjects for notification emails that can be set: 
+
+   Here is a list of subjects for notification emails that can be set:
      * `message_from_person_in_room`: Subject to use to notify about one message from one or more user(s) in a
         room which has a name. Defaults to "[%(app)s] You have a message on %(app)s from %(person)s in the %(room)s room..."
      * `message_from_person`: Subject to use to notify about one message from one or more user(s) in a
@@ -3225,13 +3215,13 @@ This setting has the following sub-options:
         a room which doesn't have a name. Defaults to "[%(app)s] You have messages on %(app)s from %(person)s..."
      * `messages_in_room`: Subject to use to notify about multiple messages in a room which has a
         name. Defaults to "[%(app)s] You have messages on %(app)s in the %(room)s room..."
-     * `messages_in_room_and_others`: Subject to use to notify about multiple messages in multiple rooms. 
+     * `messages_in_room_and_others`: Subject to use to notify about multiple messages in multiple rooms.
         Defaults to "[%(app)s] You have messages on %(app)s in the %(room)s room and others..."
      * `messages_from_person_and_others`: Subject to use to notify about multiple messages from multiple persons in
         multiple rooms. This is similar to the setting above except it's used when
-        the room in which the notification was triggered has no name. Defaults to 
+        the room in which the notification was triggered has no name. Defaults to
         "[%(app)s] You have messages on %(app)s from %(person)s and others..."
-     * `invite_from_person_to_room`: Subject to use to notify about an invite to a room which has a name. 
+     * `invite_from_person_to_room`: Subject to use to notify about an invite to a room which has a name.
         Defaults to  "[%(app)s] %(person)s has invited you to join the %(room)s room on %(app)s..."
      * `invite_from_person`: Subject to use to notify about an invite to a room which doesn't have a
         name. Defaults to "[%(app)s] %(person)s has invited you to chat on %(app)s..."
@@ -3246,6 +3236,7 @@ email:
   smtp_port: 587
   smtp_user: "exampleusername"
   smtp_pass: "examplepassword"
+  force_tls: true
   require_transport_security: true
   enable_tls: false
   notif_from: "Your Friendly %(app)s homeserver <noreply@example.com>"
@@ -3275,7 +3266,7 @@ Configuration settings related to push notifications
 ---
 ### `push`
 
-This setting defines options for push notifications. 
+This setting defines options for push notifications.
 
 This option has a number of sub-options. They are as follows:
 * `include_content`: Clients requesting push notifications can either have the body of
@@ -3290,7 +3281,7 @@ This option has a number of sub-options. They are as follows:
    notification saying only that a message arrived and who it came from.
    Defaults to true. Set to false to only include the event ID and room ID in push notification payloads.
 * `group_unread_count_by_room: false`: When a push notification is received, an unread count is also sent.
-   This number can either be calculated as the number of unread messages  for the user, or the number of *rooms* the 
+   This number can either be calculated as the number of unread messages  for the user, or the number of *rooms* the
    user has unread messages in. Defaults to true, meaning push clients will see the number of
    rooms with unread messages in them. Set to false to instead send the number
    of unread messages.
@@ -3330,7 +3321,7 @@ encryption_enabled_by_default_for_room_type: invite
 ---
 ### `user_directory`
 
-This setting defines options related to the user directory. 
+This setting defines options related to the user directory.
 
 This option has the following sub-options:
 * `enabled`:  Defines whether users can search the user directory. If false then
@@ -3348,7 +3339,7 @@ This option has the following sub-options:
     Set to true to return search results containing all known users, even if that
     user does not share a room with the requester.
 * `prefer_local_users`: Defines whether to prefer local users in search query results.
-   If set to true, local users are more likely to appear above remote users when searching the 
+   If set to true, local users are more likely to appear above remote users when searching the
    user directory. Defaults to false.
 
 Example configuration:
@@ -3364,7 +3355,7 @@ user_directory:
 For detailed instructions on user consent configuration, see [here](../../consent_tracking.md).
 
 Parts of this section are required if enabling the `consent` resource under
-`listeners`, in particular `template_dir` and `version`. # TODO: link `listeners`
+[`listeners`](#listeners), in particular `template_dir` and `version`.
 
 * `template_dir`: gives the location of the templates for the HTML forms.
   This directory should contain one subdirectory per language (eg, `en`, `fr`),
@@ -3376,7 +3367,7 @@ Parts of this section are required if enabling the `consent` resource under
    parameter.
 
 * `server_notice_content`: if enabled, will send a user a "Server Notice"
-   asking them to consent to the privacy policy. The `server_notices` section ##TODO: link
+   asking them to consent to the privacy policy. The [`server_notices` section](#server_notices)
    must also be configured for this to work. Notices will *not* be sent to
    guest users unless `send_server_notice_to_guests` is set to true.
 
@@ -3413,15 +3404,15 @@ user_consent:
 ### `stats`
 
 Settings for local room and user statistics collection. See [here](../../room_and_user_statistics.md)
-for more. 
+for more.
 
 * `enabled`: Set to false to disable room and user statistics. Note that doing
    so may cause certain features (such as the room directory) not to work
-   correctly. Defaults to true. 
+   correctly. Defaults to true.
 
 Example configuration:
 ```yaml
-stats:  
+stats:
   enabled: false
 ```
 ---
@@ -3453,7 +3444,7 @@ server_notices:
 
 Set to false to disable searching the public room list. When disabled
 blocks searching local and remote room lists for local and remote
-users by always returning an empty list for all queries. Defaults to true. 
+users by always returning an empty list for all queries. Defaults to true.
 
 Example configuration:
 ```yaml
@@ -3479,7 +3470,7 @@ Options for the rules include:
 * `user_id`: Matches against the creator of the alias. Defaults to "*".
 * `alias`: Matches against the alias being created. Defaults to "*".
 * `room_id`: Matches against the room ID the alias is being pointed at. Defaults to "*"
-* `action`: Whether to "allow" or "deny" the request if the rule matches. Defaults to allow. 
+* `action`: Whether to "allow" or "deny" the request if the rule matches. Defaults to allow.
 
 Example configuration:
 ```yaml
@@ -3509,7 +3500,7 @@ Options for the rules include:
 * `user_id`: Matches against the creator of the alias. Defaults to "*".
 * `alias`: Matches against any current local or canonical aliases associated with the room. Defaults to "*".
 * `room_id`: Matches against the room ID being published. Defaults to "*".
-* `action`: Whether to "allow" or "deny" the request if the rule matches. Defaults to allow. 
+* `action`: Whether to "allow" or "deny" the request if the rule matches. Defaults to allow.
 
 Example configuration:
 ```yaml
@@ -3561,14 +3552,14 @@ synapse or any other services which support opentracing
 Sub-options include:
 * `enabled`: whether tracing is enabled. Set to true to enable. Disabled by default.
 * `homeserver_whitelist`: The list of homeservers we wish to send and receive span contexts and span baggage.
-   See [here](../../opentracing.md) for more. 
+   See [here](../../opentracing.md) for more.
    This is a list of regexes which are matched against the `server_name` of the homeserver.
    By default, it is empty, so no servers are matched.
 * `force_tracing_for_users`: # A list of the matrix IDs of users whose requests will always be traced,
    even if the tracing system would otherwise drop the traces due to probabilistic sampling.
     By default, the list is empty.
 * `jaeger_config`: Jaeger can be configured to sample traces at different rates.
-   All configuration options provided by Jaeger can be set here. Jaeger's configuration is 
+   All configuration options provided by Jaeger can be set here. Jaeger's configuration is
    mostly related to trace sampling which is documented [here](https://www.jaegertracing.io/docs/latest/sampling/).
 
 Example configuration:
@@ -3596,7 +3587,7 @@ Configuration options related to workers.
 ### `send_federation`
 
 Controls sending of outbound federation transactions on the main process.
-Set to false if using a federation sender worker. Defaults to true. 
+Set to false if using a federation sender worker. Defaults to true.
 
 Example configuration:
 ```yaml
@@ -3606,12 +3597,12 @@ send_federation: false
 ### `federation_sender_instances`
 
 It is possible to run multiple federation sender workers, in which case the
-work is balanced across them. Use this setting to list the senders. 
+work is balanced across them. Use this setting to list the senders.
 
 This configuration setting must be shared between all federation sender workers, and if
 changed all federation sender workers must be stopped at the same time and then
 started, to ensure that all instances are running with the same config (otherwise
-events may be dropped). 
+events may be dropped).
 
 Example configuration:
 ```yaml
@@ -3622,7 +3613,7 @@ federation_sender_instances:
 ### `instance_map`
 
 When using workers this should be a map from worker name to the
-HTTP replication listener of the worker, if configured. 
+HTTP replication listener of the worker, if configured.
 
 Example configuration:
 ```yaml
@@ -3671,7 +3662,7 @@ worker_replication_secret: "secret_secret"
 Configuration for Redis when using workers. This *must* be enabled when
 using workers (unless using old style direct TCP configuration).
 This setting has the following sub-options:
-* `enabled`: whether to use Redis support. Defaults to false. 
+* `enabled`: whether to use Redis support. Defaults to false.
 * `host` and `port`: Optional host and port to use to connect to redis. Defaults to
    localhost and 6379
 * `password`: Optional password if configured on the Redis instance.
@@ -3685,7 +3676,7 @@ redis:
   password: <secret_password>
 ```
 ## Background Updates ##
-Configuration settings related to background updates. 
+Configuration settings related to background updates.
 
 ---
 ### `background_updates`
@@ -3694,7 +3685,7 @@ Background updates are database updates that are run in the background in batche
 The duration, minimum batch size, default batch size, whether to sleep between batches and if so, how long to
 sleep can all be configured. This is helpful to speed up or slow down the updates.
 This setting has the following sub-options:
-* `background_update_duration_ms`: How long in milliseconds to run a batch of background updates for. Defaults to 100. 
+* `background_update_duration_ms`: How long in milliseconds to run a batch of background updates for. Defaults to 100.
    Set a different time to change the default.
 * `sleep_enabled`: Whether to sleep between updates. Defaults to true. Set to false to change the default.
 * `sleep_duration_ms`: If sleeping between updates, how long in milliseconds to sleep for. Defaults to 1000.
@@ -3704,7 +3695,7 @@ This setting has the following sub-options:
 * `default_batch_size`: The batch size to use for the first iteration of a new background update. The default is 100.
    Set a size to change the default.
 
-Example configuration: 
+Example configuration:
 ```yaml
 background_updates:
     background_update_duration_ms: 500
diff --git a/mypy.ini b/mypy.ini
index ea0ab003a8..e2034e411f 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -1,6 +1,6 @@
 [mypy]
 namespace_packages = True
-plugins = mypy_zope:plugin, scripts-dev/mypy_synapse_plugin.py
+plugins = pydantic.mypy, mypy_zope:plugin, scripts-dev/mypy_synapse_plugin.py
 follow_imports = normal
 check_untyped_defs = True
 show_error_codes = True
@@ -84,9 +84,6 @@ disallow_untyped_defs = False
 [mypy-synapse.http.matrixfederationclient]
 disallow_untyped_defs = False
 
-[mypy-synapse.logging.opentracing]
-disallow_untyped_defs = False
-
 [mypy-synapse.metrics._reactor_metrics]
 disallow_untyped_defs = False
 # This module imports select.epoll. That exists on Linux, but doesn't on macOS.
diff --git a/poetry.lock b/poetry.lock
index 41ab40edd1..651659ec98 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -177,7 +177,7 @@ optional = false
 python-versions = "*"
 
 [package.extras]
-test = ["flake8 (==3.7.8)", "hypothesis (==3.55.3)"]
+test = ["hypothesis (==3.55.3)", "flake8 (==3.7.8)"]
 
 [[package]]
 name = "constantly"
@@ -290,7 +290,7 @@ importlib-metadata = {version = "*", markers = "python_version < \"3.8\""}
 
 [[package]]
 name = "frozendict"
-version = "2.3.2"
+version = "2.3.3"
 description = "A simple immutable dictionary"
 category = "main"
 optional = false
@@ -435,8 +435,8 @@ optional = false
 python-versions = ">=3.6"
 
 [package.extras]
-test = ["pytest", "pytest-trio", "pytest-asyncio", "testpath", "trio", "async-timeout"]
-trio = ["trio", "async-generator"]
+trio = ["async-generator", "trio"]
+test = ["async-timeout", "trio", "testpath", "pytest-asyncio", "pytest-trio", "pytest"]
 
 [[package]]
 name = "jinja2"
@@ -535,12 +535,12 @@ attrs = "*"
 importlib-metadata = {version = ">=1.4", markers = "python_version < \"3.8\""}
 
 [package.extras]
-dev = ["tox", "twisted", "aiounittest", "mypy (==0.910)", "black (==22.3.0)", "flake8 (==4.0.1)", "isort (==5.9.3)", "build (==0.8.0)", "twine (==4.0.1)"]
-test = ["tox", "twisted", "aiounittest"]
+test = ["aiounittest", "twisted", "tox"]
+dev = ["twine (==4.0.1)", "build (==0.8.0)", "isort (==5.9.3)", "flake8 (==4.0.1)", "black (==22.3.0)", "mypy (==0.910)", "aiounittest", "twisted", "tox"]
 
 [[package]]
 name = "matrix-synapse-ldap3"
-version = "0.2.1"
+version = "0.2.2"
 description = "An LDAP3 auth provider for Synapse"
 category = "main"
 optional = true
@@ -552,7 +552,7 @@ service-identity = "*"
 Twisted = ">=15.1.0"
 
 [package.extras]
-dev = ["matrix-synapse", "tox", "ldaptor", "mypy (==0.910)", "types-setuptools", "black (==22.3.0)", "flake8 (==4.0.1)", "isort (==5.9.3)"]
+dev = ["isort (==5.9.3)", "flake8 (==4.0.1)", "black (==22.3.0)", "types-setuptools", "mypy (==0.910)", "ldaptor", "tox", "matrix-synapse"]
 
 [[package]]
 name = "mccabe"
@@ -779,6 +779,21 @@ optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 
 [[package]]
+name = "pydantic"
+version = "1.9.1"
+description = "Data validation and settings management using python type hints"
+category = "main"
+optional = false
+python-versions = ">=3.6.1"
+
+[package.dependencies]
+typing-extensions = ">=3.7.4.3"
+
+[package.extras]
+dotenv = ["python-dotenv (>=0.10.4)"]
+email = ["email-validator (>=1.0.3)"]
+
+[[package]]
 name = "pyflakes"
 version = "2.4.0"
 description = "passive checker of Python programs"
@@ -820,10 +835,10 @@ optional = false
 python-versions = ">=3.6"
 
 [package.extras]
+tests = ["coverage[toml] (==5.0.4)", "pytest (>=6.0.0,<7.0.0)"]
+docs = ["zope.interface", "sphinx-rtd-theme", "sphinx"]
+dev = ["pre-commit", "mypy", "coverage[toml] (==5.0.4)", "pytest (>=6.0.0,<7.0.0)", "cryptography (>=3.3.1)", "zope.interface", "sphinx-rtd-theme", "sphinx"]
 crypto = ["cryptography (>=3.3.1)"]
-dev = ["sphinx", "sphinx-rtd-theme", "zope.interface", "cryptography (>=3.3.1)", "pytest (>=6.0.0,<7.0.0)", "coverage[toml] (==5.0.4)", "mypy", "pre-commit"]
-docs = ["sphinx", "sphinx-rtd-theme", "zope.interface"]
-tests = ["pytest (>=6.0.0,<7.0.0)", "coverage[toml] (==5.0.4)"]
 
 [[package]]
 name = "pymacaroons"
@@ -1563,7 +1578,7 @@ url_preview = ["lxml"]
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.7.1"
-content-hash = "c24bbcee7e86dbbe7cdbf49f91a25b310bf21095452641e7440129f59b077f78"
+content-hash = "7de518bf27967b3547eab8574342cfb67f87d6b47b4145c13de11112141dbf2d"
 
 [metadata.files]
 attrs = [
@@ -1753,23 +1768,23 @@ flake8-comprehensions = [
     {file = "flake8_comprehensions-3.8.0-py3-none-any.whl", hash = "sha256:9406314803abe1193c064544ab14fdc43c58424c0882f6ff8a581eb73fc9bb58"},
 ]
 frozendict = [
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-    {file = "frozendict-2.3.2-cp310-cp310-manylinux_2_17_x86_64.manylinux2014_x86_64.whl", hash = "sha256:c0a3640e9d7533d164160b758351aa49d9e85bbe0bd76d219d4021e90ffa6a52"},
-    {file = "frozendict-2.3.2-cp310-cp310-win_amd64.whl", hash = "sha256:87cfd00fafbc147d8cd2590d1109b7db8ac8d7d5bdaa708ba46caee132b55d4d"},
-    {file = "frozendict-2.3.2-cp36-cp36m-macosx_10_9_x86_64.whl", hash = "sha256:fb09761e093cfabb2f179dbfdb2521e1ec5701df714d1eb5c51fa7849027be19"},
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+    {file = "frozendict-2.3.3-cp39-cp39-win_amd64.whl", hash = "sha256:919e3609844fece11ab18bcbf28a3ed20f8108ad4149d7927d413687f281c6c9"},
+    {file = "frozendict-2.3.3-py3-none-any.whl", hash = "sha256:f988b482d08972a196664718167a993a61c9e9f6fe7b0ca2443570b5f20ca44a"},
+    {file = "frozendict-2.3.3.tar.gz", hash = "sha256:398539c52af3c647d103185bbaa1291679f0507ad035fe3bab2a8b0366d52cf1"},
 ]
 gitdb = [
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@@ -2055,8 +2070,8 @@ matrix-common = [
     {file = "matrix_common-1.2.1.tar.gz", hash = "sha256:a99dcf02a6bd95b24a5a61b354888a2ac92bf2b4b839c727b8dd9da2cdfa3853"},
 ]
 matrix-synapse-ldap3 = [
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-    {file = "matrix_synapse_ldap3-0.2.1-py3-none-any.whl", hash = "sha256:1b3310a60f1d06466f35905a269b6df95747fd1305f2b7fe638f373963b2aa2c"},
+    {file = "matrix-synapse-ldap3-0.2.2.tar.gz", hash = "sha256:b388d95693486eef69adaefd0fd9e84463d52fe17b0214a00efcaa669b73cb74"},
+    {file = "matrix_synapse_ldap3-0.2.2-py3-none-any.whl", hash = "sha256:66ee4c85d7952c6c27fd04c09cdfdf4847b8e8b7d6a7ada6ba1100013bda060f"},
 ]
 mccabe = [
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@@ -2260,6 +2275,43 @@ pycparser = [
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     {file = "pycparser-2.21.tar.gz", hash = "sha256:e644fdec12f7872f86c58ff790da456218b10f863970249516d60a5eaca77206"},
 ]
+pydantic = [
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+    {file = "pydantic-1.9.1-cp38-cp38-manylinux_2_17_x86_64.manylinux2014_x86_64.whl", hash = "sha256:5d93d4e95eacd313d2c765ebe40d49ca9dd2ed90e5b37d0d421c597af830c195"},
+    {file = "pydantic-1.9.1-cp38-cp38-manylinux_2_5_i686.manylinux1_i686.manylinux_2_17_i686.manylinux2014_i686.whl", hash = "sha256:1542636a39c4892c4f4fa6270696902acb186a9aaeac6f6cf92ce6ae2e88564b"},
+    {file = "pydantic-1.9.1-cp38-cp38-musllinux_1_1_i686.whl", hash = "sha256:a9af62e9b5b9bc67b2a195ebc2c2662fdf498a822d62f902bf27cccb52dbbf49"},
+    {file = "pydantic-1.9.1-cp38-cp38-musllinux_1_1_x86_64.whl", hash = "sha256:fe4670cb32ea98ffbf5a1262f14c3e102cccd92b1869df3bb09538158ba90fe6"},
+    {file = "pydantic-1.9.1-cp38-cp38-win_amd64.whl", hash = "sha256:9f659a5ee95c8baa2436d392267988fd0f43eb774e5eb8739252e5a7e9cf07e0"},
+    {file = "pydantic-1.9.1-cp39-cp39-macosx_10_9_x86_64.whl", hash = "sha256:b83ba3825bc91dfa989d4eed76865e71aea3a6ca1388b59fc801ee04c4d8d0d6"},
+    {file = "pydantic-1.9.1-cp39-cp39-macosx_11_0_arm64.whl", hash = "sha256:1dd8fecbad028cd89d04a46688d2fcc14423e8a196d5b0a5c65105664901f810"},
+    {file = "pydantic-1.9.1-cp39-cp39-manylinux_2_17_x86_64.manylinux2014_x86_64.whl", hash = "sha256:02eefd7087268b711a3ff4db528e9916ac9aa18616da7bca69c1871d0b7a091f"},
+    {file = "pydantic-1.9.1-cp39-cp39-manylinux_2_5_i686.manylinux1_i686.manylinux_2_17_i686.manylinux2014_i686.whl", hash = "sha256:7eb57ba90929bac0b6cc2af2373893d80ac559adda6933e562dcfb375029acee"},
+    {file = "pydantic-1.9.1-cp39-cp39-musllinux_1_1_i686.whl", hash = "sha256:4ce9ae9e91f46c344bec3b03d6ee9612802682c1551aaf627ad24045ce090761"},
+    {file = "pydantic-1.9.1-cp39-cp39-musllinux_1_1_x86_64.whl", hash = "sha256:72ccb318bf0c9ab97fc04c10c37683d9eea952ed526707fabf9ac5ae59b701fd"},
+    {file = "pydantic-1.9.1-cp39-cp39-win_amd64.whl", hash = "sha256:61b6760b08b7c395975d893e0b814a11cf011ebb24f7d869e7118f5a339a82e1"},
+    {file = "pydantic-1.9.1-py3-none-any.whl", hash = "sha256:4988c0f13c42bfa9ddd2fe2f569c9d54646ce84adc5de84228cfe83396f3bd58"},
+    {file = "pydantic-1.9.1.tar.gz", hash = "sha256:1ed987c3ff29fff7fd8c3ea3a3ea877ad310aae2ef9889a119e22d3f2db0691a"},
+]
 pyflakes = [
     {file = "pyflakes-2.4.0-py2.py3-none-any.whl", hash = "sha256:3bb3a3f256f4b7968c9c788781e4ff07dce46bdf12339dcda61053375426ee2e"},
     {file = "pyflakes-2.4.0.tar.gz", hash = "sha256:05a85c2872edf37a4ed30b0cce2f6093e1d0581f8c19d7393122da7e25b2b24c"},
diff --git a/pyproject.toml b/pyproject.toml
index 4da1331c93..745b6067aa 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -54,7 +54,7 @@ skip_gitignore = true
 
 [tool.poetry]
 name = "matrix-synapse"
-version = "1.63.1"
+version = "1.66.0rc1"
 description = "Homeserver for the Matrix decentralised comms protocol"
 authors = ["Matrix.org Team and Contributors <packages@matrix.org>"]
 license = "Apache-2.0"
@@ -158,6 +158,9 @@ packaging = ">=16.1"
 # At the time of writing, we only use functions from the version `importlib.metadata`
 # which shipped in Python 3.8. This corresponds to version 1.4 of the backport.
 importlib_metadata = { version = ">=1.4", python = "<3.8" }
+# This is the most recent version of Pydantic with available on common distros.
+pydantic = ">=1.7.4"
+
 
 
 # Optional Dependencies
diff --git a/scripts-dev/check_pydantic_models.py b/scripts-dev/check_pydantic_models.py
new file mode 100755
index 0000000000..d0fb811bdb
--- /dev/null
+++ b/scripts-dev/check_pydantic_models.py
@@ -0,0 +1,425 @@
+#! /usr/bin/env python
+# Copyright 2022 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""
+A script which enforces that Synapse always uses strict types when defining a Pydantic
+model.
+
+Pydantic does not yet offer a strict mode, but it is planned for pydantic v2. See
+
+    https://github.com/pydantic/pydantic/issues/1098
+    https://pydantic-docs.helpmanual.io/blog/pydantic-v2/#strict-mode
+
+until then, this script is a best effort to stop us from introducing type coersion bugs
+(like the infamous stringy power levels fixed in room version 10).
+"""
+import argparse
+import contextlib
+import functools
+import importlib
+import logging
+import os
+import pkgutil
+import sys
+import textwrap
+import traceback
+import unittest.mock
+from contextlib import contextmanager
+from typing import Any, Callable, Dict, Generator, List, Set, Type, TypeVar
+
+from parameterized import parameterized
+from pydantic import BaseModel as PydanticBaseModel, conbytes, confloat, conint, constr
+from pydantic.typing import get_args
+from typing_extensions import ParamSpec
+
+logger = logging.getLogger(__name__)
+
+CONSTRAINED_TYPE_FACTORIES_WITH_STRICT_FLAG: List[Callable] = [
+    constr,
+    conbytes,
+    conint,
+    confloat,
+]
+
+TYPES_THAT_PYDANTIC_WILL_COERCE_TO = [
+    str,
+    bytes,
+    int,
+    float,
+    bool,
+]
+
+
+P = ParamSpec("P")
+R = TypeVar("R")
+
+
+class ModelCheckerException(Exception):
+    """Dummy exception. Allows us to detect unwanted types during a module import."""
+
+
+class MissingStrictInConstrainedTypeException(ModelCheckerException):
+    factory_name: str
+
+    def __init__(self, factory_name: str):
+        self.factory_name = factory_name
+
+
+class FieldHasUnwantedTypeException(ModelCheckerException):
+    message: str
+
+    def __init__(self, message: str):
+        self.message = message
+
+
+def make_wrapper(factory: Callable[P, R]) -> Callable[P, R]:
+    """We patch `constr` and friends with wrappers that enforce strict=True."""
+
+    @functools.wraps(factory)
+    def wrapper(*args: P.args, **kwargs: P.kwargs) -> R:
+        # type-ignore: should be redundant once we can use https://github.com/python/mypy/pull/12668
+        if "strict" not in kwargs:  # type: ignore[attr-defined]
+            raise MissingStrictInConstrainedTypeException(factory.__name__)
+        if not kwargs["strict"]:  # type: ignore[index]
+            raise MissingStrictInConstrainedTypeException(factory.__name__)
+        return factory(*args, **kwargs)
+
+    return wrapper
+
+
+def field_type_unwanted(type_: Any) -> bool:
+    """Very rough attempt to detect if a type is unwanted as a Pydantic annotation.
+
+    At present, we exclude types which will coerce, or any generic type involving types
+    which will coerce."""
+    logger.debug("Is %s unwanted?")
+    if type_ in TYPES_THAT_PYDANTIC_WILL_COERCE_TO:
+        logger.debug("yes")
+        return True
+    logger.debug("Maybe. Subargs are %s", get_args(type_))
+    rv = any(field_type_unwanted(t) for t in get_args(type_))
+    logger.debug("Conclusion: %s %s unwanted", type_, "is" if rv else "is not")
+    return rv
+
+
+class PatchedBaseModel(PydanticBaseModel):
+    """A patched version of BaseModel that inspects fields after models are defined.
+
+    We complain loudly if we see an unwanted type.
+
+    Beware: ModelField.type_ is presumably private; this is likely to be very brittle.
+    """
+
+    @classmethod
+    def __init_subclass__(cls: Type[PydanticBaseModel], **kwargs: object):
+        for field in cls.__fields__.values():
+            # Note that field.type_ and field.outer_type are computed based on the
+            # annotation type, see pydantic.fields.ModelField._type_analysis
+            if field_type_unwanted(field.outer_type_):
+                # TODO: this only reports the first bad field. Can we find all bad ones
+                #  and report them all?
+                raise FieldHasUnwantedTypeException(
+                    f"{cls.__module__}.{cls.__qualname__} has field '{field.name}' "
+                    f"with unwanted type `{field.outer_type_}`"
+                )
+
+
+@contextmanager
+def monkeypatch_pydantic() -> Generator[None, None, None]:
+    """Patch pydantic with our snooping versions of BaseModel and the con* functions.
+
+    If the snooping functions see something they don't like, they'll raise a
+    ModelCheckingException instance.
+    """
+    with contextlib.ExitStack() as patches:
+        # Most Synapse code ought to import the patched objects directly from
+        # `pydantic`. But we also patch their containing modules `pydantic.main` and
+        # `pydantic.types` for completeness.
+        patch_basemodel1 = unittest.mock.patch(
+            "pydantic.BaseModel", new=PatchedBaseModel
+        )
+        patch_basemodel2 = unittest.mock.patch(
+            "pydantic.main.BaseModel", new=PatchedBaseModel
+        )
+        patches.enter_context(patch_basemodel1)
+        patches.enter_context(patch_basemodel2)
+        for factory in CONSTRAINED_TYPE_FACTORIES_WITH_STRICT_FLAG:
+            wrapper: Callable = make_wrapper(factory)
+            patch1 = unittest.mock.patch(f"pydantic.{factory.__name__}", new=wrapper)
+            patch2 = unittest.mock.patch(
+                f"pydantic.types.{factory.__name__}", new=wrapper
+            )
+            patches.enter_context(patch1)
+            patches.enter_context(patch2)
+        yield
+
+
+def format_model_checker_exception(e: ModelCheckerException) -> str:
+    """Work out which line of code caused e. Format the line in a human-friendly way."""
+    # TODO. FieldHasUnwantedTypeException gives better error messages. Can we ditch the
+    #   patches of constr() etc, and instead inspect fields to look for ConstrainedStr
+    #   with strict=False? There is some difficulty with the inheritance hierarchy
+    #   because StrictStr < ConstrainedStr < str.
+    if isinstance(e, FieldHasUnwantedTypeException):
+        return e.message
+    elif isinstance(e, MissingStrictInConstrainedTypeException):
+        frame_summary = traceback.extract_tb(e.__traceback__)[-2]
+        return (
+            f"Missing `strict=True` from {e.factory_name}() call \n"
+            + traceback.format_list([frame_summary])[0].lstrip()
+        )
+    else:
+        raise ValueError(f"Unknown exception {e}") from e
+
+
+def lint() -> int:
+    """Try to import all of Synapse and see if we spot any Pydantic type coercions.
+
+    Print any problems, then return a status code suitable for sys.exit."""
+    failures = do_lint()
+    if failures:
+        print(f"Found {len(failures)} problem(s)")
+    for failure in sorted(failures):
+        print(failure)
+    return os.EX_DATAERR if failures else os.EX_OK
+
+
+def do_lint() -> Set[str]:
+    """Try to import all of Synapse and see if we spot any Pydantic type coercions."""
+    failures = set()
+
+    with monkeypatch_pydantic():
+        logger.debug("Importing synapse")
+        try:
+            # TODO: make "synapse" an argument so we can target this script at
+            # a subpackage
+            module = importlib.import_module("synapse")
+        except ModelCheckerException as e:
+            logger.warning("Bad annotation found when importing synapse")
+            failures.add(format_model_checker_exception(e))
+            return failures
+
+        try:
+            logger.debug("Fetching subpackages")
+            module_infos = list(
+                pkgutil.walk_packages(module.__path__, f"{module.__name__}.")
+            )
+        except ModelCheckerException as e:
+            logger.warning("Bad annotation found when looking for modules to import")
+            failures.add(format_model_checker_exception(e))
+            return failures
+
+        for module_info in module_infos:
+            logger.debug("Importing %s", module_info.name)
+            try:
+                importlib.import_module(module_info.name)
+            except ModelCheckerException as e:
+                logger.warning(
+                    f"Bad annotation found when importing {module_info.name}"
+                )
+                failures.add(format_model_checker_exception(e))
+
+    return failures
+
+
+def run_test_snippet(source: str) -> None:
+    """Exec a snippet of source code in an isolated environment."""
+    # To emulate `source` being called at the top level of the module,
+    # the globals and locals we provide apparently have to be the same mapping.
+    #
+    # > Remember that at the module level, globals and locals are the same dictionary.
+    # > If exec gets two separate objects as globals and locals, the code will be
+    # > executed as if it were embedded in a class definition.
+    globals_: Dict[str, object]
+    locals_: Dict[str, object]
+    globals_ = locals_ = {}
+    exec(textwrap.dedent(source), globals_, locals_)
+
+
+class TestConstrainedTypesPatch(unittest.TestCase):
+    def test_expression_without_strict_raises(self) -> None:
+        with monkeypatch_pydantic(), self.assertRaises(ModelCheckerException):
+            run_test_snippet(
+                """
+                from pydantic import constr
+                constr()
+                """
+            )
+
+    def test_called_as_module_attribute_raises(self) -> None:
+        with monkeypatch_pydantic(), self.assertRaises(ModelCheckerException):
+            run_test_snippet(
+                """
+                import pydantic
+                pydantic.constr()
+                """
+            )
+
+    def test_wildcard_import_raises(self) -> None:
+        with monkeypatch_pydantic(), self.assertRaises(ModelCheckerException):
+            run_test_snippet(
+                """
+                from pydantic import *
+                constr()
+                """
+            )
+
+    def test_alternative_import_raises(self) -> None:
+        with monkeypatch_pydantic(), self.assertRaises(ModelCheckerException):
+            run_test_snippet(
+                """
+                from pydantic.types import constr
+                constr()
+                """
+            )
+
+    def test_alternative_import_attribute_raises(self) -> None:
+        with monkeypatch_pydantic(), self.assertRaises(ModelCheckerException):
+            run_test_snippet(
+                """
+                import pydantic.types
+                pydantic.types.constr()
+                """
+            )
+
+    def test_kwarg_but_no_strict_raises(self) -> None:
+        with monkeypatch_pydantic(), self.assertRaises(ModelCheckerException):
+            run_test_snippet(
+                """
+                from pydantic import constr
+                constr(min_length=10)
+                """
+            )
+
+    def test_kwarg_strict_False_raises(self) -> None:
+        with monkeypatch_pydantic(), self.assertRaises(ModelCheckerException):
+            run_test_snippet(
+                """
+                from pydantic import constr
+                constr(strict=False)
+                """
+            )
+
+    def test_kwarg_strict_True_doesnt_raise(self) -> None:
+        with monkeypatch_pydantic():
+            run_test_snippet(
+                """
+                from pydantic import constr
+                constr(strict=True)
+                """
+            )
+
+    def test_annotation_without_strict_raises(self) -> None:
+        with monkeypatch_pydantic(), self.assertRaises(ModelCheckerException):
+            run_test_snippet(
+                """
+                from pydantic import constr
+                x: constr()
+                """
+            )
+
+    def test_field_annotation_without_strict_raises(self) -> None:
+        with monkeypatch_pydantic(), self.assertRaises(ModelCheckerException):
+            run_test_snippet(
+                """
+                from pydantic import BaseModel, conint
+                class C:
+                    x: conint()
+                """
+            )
+
+
+class TestFieldTypeInspection(unittest.TestCase):
+    @parameterized.expand(
+        [
+            ("str",),
+            ("bytes"),
+            ("int",),
+            ("float",),
+            ("bool"),
+            ("Optional[str]",),
+            ("Union[None, str]",),
+            ("List[str]",),
+            ("List[List[str]]",),
+            ("Dict[StrictStr, str]",),
+            ("Dict[str, StrictStr]",),
+            ("TypedDict('D', x=int)",),
+        ]
+    )
+    def test_field_holding_unwanted_type_raises(self, annotation: str) -> None:
+        with monkeypatch_pydantic(), self.assertRaises(ModelCheckerException):
+            run_test_snippet(
+                f"""
+                from typing import *
+                from pydantic import *
+                class C(BaseModel):
+                    f: {annotation}
+                """
+            )
+
+    @parameterized.expand(
+        [
+            ("StrictStr",),
+            ("StrictBytes"),
+            ("StrictInt",),
+            ("StrictFloat",),
+            ("StrictBool"),
+            ("constr(strict=True, min_length=10)",),
+            ("Optional[StrictStr]",),
+            ("Union[None, StrictStr]",),
+            ("List[StrictStr]",),
+            ("List[List[StrictStr]]",),
+            ("Dict[StrictStr, StrictStr]",),
+            ("TypedDict('D', x=StrictInt)",),
+        ]
+    )
+    def test_field_holding_accepted_type_doesnt_raise(self, annotation: str) -> None:
+        with monkeypatch_pydantic():
+            run_test_snippet(
+                f"""
+                from typing import *
+                from pydantic import *
+                class C(BaseModel):
+                    f: {annotation}
+                """
+            )
+
+    def test_field_holding_str_raises_with_alternative_import(self) -> None:
+        with monkeypatch_pydantic(), self.assertRaises(ModelCheckerException):
+            run_test_snippet(
+                """
+                from pydantic.main import BaseModel
+                class C(BaseModel):
+                    f: str
+                """
+            )
+
+
+parser = argparse.ArgumentParser()
+parser.add_argument("mode", choices=["lint", "test"], default="lint", nargs="?")
+parser.add_argument("-v", "--verbose", action="store_true")
+
+
+if __name__ == "__main__":
+    args = parser.parse_args(sys.argv[1:])
+    logging.basicConfig(
+        format="%(asctime)s %(name)s:%(lineno)d %(levelname)s %(message)s",
+        level=logging.DEBUG if args.verbose else logging.INFO,
+    )
+    # suppress logs we don't care about
+    logging.getLogger("xmlschema").setLevel(logging.WARNING)
+    if args.mode == "lint":
+        sys.exit(lint())
+    elif args.mode == "test":
+        unittest.main(argv=sys.argv[:1])
diff --git a/scripts-dev/complement.sh b/scripts-dev/complement.sh
index 6381f7092e..eab23f18f1 100755
--- a/scripts-dev/complement.sh
+++ b/scripts-dev/complement.sh
@@ -101,6 +101,7 @@ if [ -z "$skip_docker_build" ]; then
     echo_if_github "::group::Build Docker image: matrixdotorg/synapse"
     docker build -t matrixdotorg/synapse \
       --build-arg TEST_ONLY_SKIP_DEP_HASH_VERIFICATION \
+      --build-arg TEST_ONLY_IGNORE_POETRY_LOCKFILE \
       -f "docker/Dockerfile" .
     echo_if_github "::endgroup::"
 
diff --git a/scripts-dev/lint.sh b/scripts-dev/lint.sh
index 377348b107..bf900645b1 100755
--- a/scripts-dev/lint.sh
+++ b/scripts-dev/lint.sh
@@ -106,4 +106,5 @@ isort "${files[@]}"
 python3 -m black "${files[@]}"
 ./scripts-dev/config-lint.sh
 flake8 "${files[@]}"
+./scripts-dev/check_pydantic_models.py lint
 mypy
diff --git a/scripts-dev/release.py b/scripts-dev/release.py
index 0031ba3e4b..46220c4dd3 100755
--- a/scripts-dev/release.py
+++ b/scripts-dev/release.py
@@ -32,6 +32,7 @@ import click
 import commonmark
 import git
 from click.exceptions import ClickException
+from git import GitCommandError, Repo
 from github import Github
 from packaging import version
 
@@ -55,9 +56,12 @@ def run_until_successful(
 def cli() -> None:
     """An interactive script to walk through the parts of creating a release.
 
-    Requires the dev dependencies be installed, which can be done via:
+    Requirements:
+      - The dev dependencies be installed, which can be done via:
 
-        pip install -e .[dev]
+            pip install -e .[dev]
+
+      - A checkout of the sytest repository at ../sytest
 
     Then to use:
 
@@ -75,6 +79,8 @@ def cli() -> None:
 
         # Optional: generate some nice links for the announcement
 
+        ./scripts-dev/release.py merge-back
+
         ./scripts-dev/release.py announce
 
     If the env var GH_TOKEN (or GITHUB_TOKEN) is set, or passed into the
@@ -89,10 +95,12 @@ def prepare() -> None:
     """
 
     # Make sure we're in a git repo.
-    repo = get_repo_and_check_clean_checkout()
+    synapse_repo = get_repo_and_check_clean_checkout()
+    sytest_repo = get_repo_and_check_clean_checkout("../sytest", "sytest")
 
-    click.secho("Updating git repo...")
-    repo.remote().fetch()
+    click.secho("Updating Synapse and Sytest git repos...")
+    synapse_repo.remote().fetch()
+    sytest_repo.remote().fetch()
 
     # Get the current version and AST from root Synapse module.
     current_version = get_package_version()
@@ -166,12 +174,12 @@ def prepare() -> None:
     assert not parsed_new_version.is_postrelease
 
     release_branch_name = get_release_branch_name(parsed_new_version)
-    release_branch = find_ref(repo, release_branch_name)
+    release_branch = find_ref(synapse_repo, release_branch_name)
     if release_branch:
         if release_branch.is_remote():
             # If the release branch only exists on the remote we check it out
             # locally.
-            repo.git.checkout(release_branch_name)
+            synapse_repo.git.checkout(release_branch_name)
     else:
         # If a branch doesn't exist we create one. We ask which one branch it
         # should be based off, defaulting to sensible values depending on the
@@ -187,25 +195,34 @@ def prepare() -> None:
             "Which branch should the release be based on?", default=default
         )
 
-        base_branch = find_ref(repo, branch_name)
-        if not base_branch:
-            print(f"Could not find base branch {branch_name}!")
-            click.get_current_context().abort()
+        for repo_name, repo in {"synapse": synapse_repo, "sytest": sytest_repo}.items():
+            base_branch = find_ref(repo, branch_name)
+            if not base_branch:
+                print(f"Could not find base branch {branch_name} for {repo_name}!")
+                click.get_current_context().abort()
+
+            # Check out the base branch and ensure it's up to date
+            repo.head.set_reference(
+                base_branch, f"check out the base branch for {repo_name}"
+            )
+            repo.head.reset(index=True, working_tree=True)
+            if not base_branch.is_remote():
+                update_branch(repo)
 
-        # Check out the base branch and ensure it's up to date
-        repo.head.set_reference(base_branch, "check out the base branch")
-        repo.head.reset(index=True, working_tree=True)
-        if not base_branch.is_remote():
-            update_branch(repo)
+            # Create the new release branch
+            # Type ignore will no longer be needed after GitPython 3.1.28.
+            # See https://github.com/gitpython-developers/GitPython/pull/1419
+            repo.create_head(release_branch_name, commit=base_branch)  # type: ignore[arg-type]
 
-        # Create the new release branch
-        # Type ignore will no longer be needed after GitPython 3.1.28.
-        # See https://github.com/gitpython-developers/GitPython/pull/1419
-        repo.create_head(release_branch_name, commit=base_branch)  # type: ignore[arg-type]
+        # Special-case SyTest: we don't actually prepare any files so we may
+        # as well push it now (and only when we create a release branch;
+        # not on subsequent RCs or full releases).
+        if click.confirm("Push new SyTest branch?", default=True):
+            sytest_repo.git.push("-u", sytest_repo.remote().name, release_branch_name)
 
     # Switch to the release branch and ensure it's up to date.
-    repo.git.checkout(release_branch_name)
-    update_branch(repo)
+    synapse_repo.git.checkout(release_branch_name)
+    update_branch(synapse_repo)
 
     # Update the version specified in pyproject.toml.
     subprocess.check_output(["poetry", "version", new_version])
@@ -230,15 +247,15 @@ def prepare() -> None:
     run_until_successful('dch -M -r -D stable ""', shell=True)
 
     # Show the user the changes and ask if they want to edit the change log.
-    repo.git.add("-u")
+    synapse_repo.git.add("-u")
     subprocess.run("git diff --cached", shell=True)
 
     if click.confirm("Edit changelog?", default=False):
         click.edit(filename="CHANGES.md")
 
     # Commit the changes.
-    repo.git.add("-u")
-    repo.git.commit("-m", new_version)
+    synapse_repo.git.add("-u")
+    synapse_repo.git.commit("-m", new_version)
 
     # We give the option to bail here in case the user wants to make sure things
     # are OK before pushing.
@@ -246,17 +263,21 @@ def prepare() -> None:
         print("")
         print("Run when ready to push:")
         print("")
-        print(f"\tgit push -u {repo.remote().name} {repo.active_branch.name}")
+        print(
+            f"\tgit push -u {synapse_repo.remote().name} {synapse_repo.active_branch.name}"
+        )
         print("")
         sys.exit(0)
 
     # Otherwise, push and open the changelog in the browser.
-    repo.git.push("-u", repo.remote().name, repo.active_branch.name)
+    synapse_repo.git.push(
+        "-u", synapse_repo.remote().name, synapse_repo.active_branch.name
+    )
 
     print("Opening the changelog in your browser...")
     print("Please ask others to give it a check.")
     click.launch(
-        f"https://github.com/matrix-org/synapse/blob/{repo.active_branch.name}/CHANGES.md"
+        f"https://github.com/matrix-org/synapse/blob/{synapse_repo.active_branch.name}/CHANGES.md"
     )
 
 
@@ -423,6 +444,79 @@ def upload() -> None:
     )
 
 
+def _merge_into(repo: Repo, source: str, target: str) -> None:
+    """
+    Merges branch `source` into branch `target`.
+    Pulls both before merging and pushes the result.
+    """
+
+    # Update our branches and switch to the target branch
+    for branch in [source, target]:
+        click.echo(f"Switching to {branch} and pulling...")
+        repo.heads[branch].checkout()
+        # Pull so we're up to date
+        repo.remote().pull()
+
+    assert repo.active_branch.name == target
+
+    try:
+        # TODO This seemed easier than using GitPython directly
+        click.echo(f"Merging {source}...")
+        repo.git.merge(source)
+    except GitCommandError as exc:
+        # If a merge conflict occurs, give some context and try to
+        # make it easy to abort if necessary.
+        click.echo(exc)
+        if not click.confirm(
+            f"Likely merge conflict whilst merging ({source} → {target}). "
+            f"Have you resolved it?"
+        ):
+            repo.git.merge("--abort")
+            return
+
+    # Push result.
+    click.echo("Pushing...")
+    repo.remote().push()
+
+
+@cli.command()
+def merge_back() -> None:
+    """Merge the release branch back into the appropriate branches.
+    All branches will be automatically pulled from the remote and the results
+    will be pushed to the remote."""
+
+    synapse_repo = get_repo_and_check_clean_checkout()
+    branch_name = synapse_repo.active_branch.name
+
+    if not branch_name.startswith("release-v"):
+        raise RuntimeError("Not on a release branch. This does not seem sensible.")
+
+    # Pull so we're up to date
+    synapse_repo.remote().pull()
+
+    current_version = get_package_version()
+
+    if current_version.is_prerelease:
+        # Release candidate
+        if click.confirm(f"Merge {branch_name} → develop?", default=True):
+            _merge_into(synapse_repo, branch_name, "develop")
+    else:
+        # Full release
+        sytest_repo = get_repo_and_check_clean_checkout("../sytest", "sytest")
+
+        if click.confirm(f"Merge {branch_name} → master?", default=True):
+            _merge_into(synapse_repo, branch_name, "master")
+
+        if click.confirm("Merge master → develop?", default=True):
+            _merge_into(synapse_repo, "master", "develop")
+
+        if click.confirm(f"On SyTest, merge {branch_name} → master?", default=True):
+            _merge_into(sytest_repo, branch_name, "master")
+
+        if click.confirm("On SyTest, merge master → develop?", default=True):
+            _merge_into(sytest_repo, "master", "develop")
+
+
 @cli.command()
 def announce() -> None:
     """Generate markdown to announce the release."""
@@ -469,14 +563,18 @@ def get_release_branch_name(version_number: version.Version) -> str:
     return f"release-v{version_number.major}.{version_number.minor}"
 
 
-def get_repo_and_check_clean_checkout() -> git.Repo:
+def get_repo_and_check_clean_checkout(
+    path: str = ".", name: str = "synapse"
+) -> git.Repo:
     """Get the project repo and check it's not got any uncommitted changes."""
     try:
-        repo = git.Repo()
+        repo = git.Repo(path=path)
     except git.InvalidGitRepositoryError:
-        raise click.ClickException("Not in Synapse repo.")
+        raise click.ClickException(
+            f"{path} is not a git repository (expecting a {name} repository)."
+        )
     if repo.is_dirty():
-        raise click.ClickException("Uncommitted changes exist.")
+        raise click.ClickException(f"Uncommitted changes exist in {path}.")
     return repo
 
 
diff --git a/synapse/api/auth.py b/synapse/api/auth.py
index 6e6eaf3805..9a1aea083f 100644
--- a/synapse/api/auth.py
+++ b/synapse/api/auth.py
@@ -26,13 +26,18 @@ from synapse.api.errors import (
     Codes,
     InvalidClientTokenError,
     MissingClientTokenError,
+    UnstableSpecAuthError,
 )
 from synapse.appservice import ApplicationService
 from synapse.http import get_request_user_agent
 from synapse.http.site import SynapseRequest
-from synapse.logging.opentracing import active_span, force_tracing, start_active_span
-from synapse.storage.databases.main.registration import TokenLookupResult
-from synapse.types import Requester, UserID, create_requester
+from synapse.logging.opentracing import (
+    active_span,
+    force_tracing,
+    start_active_span,
+    trace,
+)
+from synapse.types import Requester, create_requester
 
 if TYPE_CHECKING:
     from synapse.server import HomeServer
@@ -64,14 +69,14 @@ class Auth:
     async def check_user_in_room(
         self,
         room_id: str,
-        user_id: str,
+        requester: Requester,
         allow_departed_users: bool = False,
     ) -> Tuple[str, Optional[str]]:
         """Check if the user is in the room, or was at some point.
         Args:
             room_id: The room to check.
 
-            user_id: The user to check.
+            requester: The user making the request, according to the access token.
 
             current_state: Optional map of the current state of the room.
                 If provided then that map is used to check whether they are a
@@ -88,6 +93,7 @@ class Auth:
             membership event ID of the user.
         """
 
+        user_id = requester.user.to_string()
         (
             membership,
             member_event_id,
@@ -106,8 +112,11 @@ class Auth:
                 forgot = await self.store.did_forget(user_id, room_id)
                 if not forgot:
                     return membership, member_event_id
-
-        raise AuthError(403, "User %s not in room %s" % (user_id, room_id))
+        raise UnstableSpecAuthError(
+            403,
+            "User %s not in room %s" % (user_id, room_id),
+            errcode=Codes.NOT_JOINED,
+        )
 
     async def get_user_by_req(
         self,
@@ -173,96 +182,69 @@ class Auth:
 
             access_token = self.get_access_token_from_request(request)
 
-            (
-                user_id,
-                device_id,
-                app_service,
-            ) = await self._get_appservice_user_id_and_device_id(request)
-            if user_id and app_service:
-                if ip_addr and self._track_appservice_user_ips:
-                    await self.store.insert_client_ip(
-                        user_id=user_id,
-                        access_token=access_token,
-                        ip=ip_addr,
-                        user_agent=user_agent,
-                        device_id="dummy-device"
-                        if device_id is None
-                        else device_id,  # stubbed
-                    )
-
-                requester = create_requester(
-                    user_id, app_service=app_service, device_id=device_id
+            # First check if it could be a request from an appservice
+            requester = await self._get_appservice_user(request)
+            if not requester:
+                # If not, it should be from a regular user
+                requester = await self.get_user_by_access_token(
+                    access_token, allow_expired=allow_expired
                 )
 
-                request.requester = user_id
-                return requester
-
-            user_info = await self.get_user_by_access_token(
-                access_token, allow_expired=allow_expired
-            )
-            token_id = user_info.token_id
-            is_guest = user_info.is_guest
-            shadow_banned = user_info.shadow_banned
-
-            # Deny the request if the user account has expired.
-            if not allow_expired:
-                if await self._account_validity_handler.is_user_expired(
-                    user_info.user_id
-                ):
-                    # Raise the error if either an account validity module has determined
-                    # the account has expired, or the legacy account validity
-                    # implementation is enabled and determined the account has expired
-                    raise AuthError(
-                        403,
-                        "User account has expired",
-                        errcode=Codes.EXPIRED_ACCOUNT,
-                    )
-
-            device_id = user_info.device_id
-
-            if access_token and ip_addr:
+                # Deny the request if the user account has expired.
+                # This check is only done for regular users, not appservice ones.
+                if not allow_expired:
+                    if await self._account_validity_handler.is_user_expired(
+                        requester.user.to_string()
+                    ):
+                        # Raise the error if either an account validity module has determined
+                        # the account has expired, or the legacy account validity
+                        # implementation is enabled and determined the account has expired
+                        raise AuthError(
+                            403,
+                            "User account has expired",
+                            errcode=Codes.EXPIRED_ACCOUNT,
+                        )
+
+            if ip_addr and (
+                not requester.app_service or self._track_appservice_user_ips
+            ):
+                # XXX(quenting): I'm 95% confident that we could skip setting the
+                # device_id to "dummy-device" for appservices, and that the only impact
+                # would be some rows which whould not deduplicate in the 'user_ips'
+                # table during the transition
+                recorded_device_id = (
+                    "dummy-device"
+                    if requester.device_id is None and requester.app_service is not None
+                    else requester.device_id
+                )
                 await self.store.insert_client_ip(
-                    user_id=user_info.token_owner,
+                    user_id=requester.authenticated_entity,
                     access_token=access_token,
                     ip=ip_addr,
                     user_agent=user_agent,
-                    device_id=device_id,
+                    device_id=recorded_device_id,
                 )
+
                 # Track also the puppeted user client IP if enabled and the user is puppeting
                 if (
-                    user_info.user_id != user_info.token_owner
+                    requester.user.to_string() != requester.authenticated_entity
                     and self._track_puppeted_user_ips
                 ):
                     await self.store.insert_client_ip(
-                        user_id=user_info.user_id,
+                        user_id=requester.user.to_string(),
                         access_token=access_token,
                         ip=ip_addr,
                         user_agent=user_agent,
-                        device_id=device_id,
+                        device_id=requester.device_id,
                     )
 
-            if is_guest and not allow_guest:
+            if requester.is_guest and not allow_guest:
                 raise AuthError(
                     403,
                     "Guest access not allowed",
                     errcode=Codes.GUEST_ACCESS_FORBIDDEN,
                 )
 
-            # Mark the token as used. This is used to invalidate old refresh
-            # tokens after some time.
-            if not user_info.token_used and token_id is not None:
-                await self.store.mark_access_token_as_used(token_id)
-
-            requester = create_requester(
-                user_info.user_id,
-                token_id,
-                is_guest,
-                shadow_banned,
-                device_id,
-                app_service=app_service,
-                authenticated_entity=user_info.token_owner,
-            )
-
             request.requester = requester
             return requester
         except KeyError:
@@ -299,9 +281,7 @@ class Auth:
                 403, "Application service has not registered this user (%s)" % user_id
             )
 
-    async def _get_appservice_user_id_and_device_id(
-        self, request: Request
-    ) -> Tuple[Optional[str], Optional[str], Optional[ApplicationService]]:
+    async def _get_appservice_user(self, request: Request) -> Optional[Requester]:
         """
         Given a request, reads the request parameters to determine:
         - whether it's an application service that's making this request
@@ -316,15 +296,13 @@ class Auth:
              Must use `org.matrix.msc3202.device_id` in place of `device_id` for now.
 
         Returns:
-            3-tuple of
-            (user ID?, device ID?, application service?)
+            the application service `Requester` of that request
 
         Postconditions:
-        - If an application service is returned, so is a user ID
-        - A user ID is never returned without an application service
-        - A device ID is never returned without a user ID or an application service
-        - The returned application service, if present, is permitted to control the
-          returned user ID.
+        - The `app_service` field in the returned `Requester` is set
+        - The `user_id` field in the returned `Requester` is either the application
+          service sender or the controlled user set by the `user_id` URI parameter
+        - The returned application service is permitted to control the returned user ID.
         - The returned device ID, if present, has been checked to be a valid device ID
           for the returned user ID.
         """
@@ -334,12 +312,12 @@ class Auth:
             self.get_access_token_from_request(request)
         )
         if app_service is None:
-            return None, None, None
+            return None
 
         if app_service.ip_range_whitelist:
             ip_address = IPAddress(request.getClientAddress().host)
             if ip_address not in app_service.ip_range_whitelist:
-                return None, None, None
+                return None
 
         # This will always be set by the time Twisted calls us.
         assert request.args is not None
@@ -373,13 +351,15 @@ class Auth:
                     Codes.EXCLUSIVE,
                 )
 
-        return effective_user_id, effective_device_id, app_service
+        return create_requester(
+            effective_user_id, app_service=app_service, device_id=effective_device_id
+        )
 
     async def get_user_by_access_token(
         self,
         token: str,
         allow_expired: bool = False,
-    ) -> TokenLookupResult:
+    ) -> Requester:
         """Validate access token and get user_id from it
 
         Args:
@@ -396,9 +376,9 @@ class Auth:
 
         # First look in the database to see if the access token is present
         # as an opaque token.
-        r = await self.store.get_user_by_access_token(token)
-        if r:
-            valid_until_ms = r.valid_until_ms
+        user_info = await self.store.get_user_by_access_token(token)
+        if user_info:
+            valid_until_ms = user_info.valid_until_ms
             if (
                 not allow_expired
                 and valid_until_ms is not None
@@ -410,7 +390,20 @@ class Auth:
                     msg="Access token has expired", soft_logout=True
                 )
 
-            return r
+            # Mark the token as used. This is used to invalidate old refresh
+            # tokens after some time.
+            await self.store.mark_access_token_as_used(user_info.token_id)
+
+            requester = create_requester(
+                user_id=user_info.user_id,
+                access_token_id=user_info.token_id,
+                is_guest=user_info.is_guest,
+                shadow_banned=user_info.shadow_banned,
+                device_id=user_info.device_id,
+                authenticated_entity=user_info.token_owner,
+            )
+
+            return requester
 
         # If the token isn't found in the database, then it could still be a
         # macaroon for a guest, so we check that here.
@@ -436,11 +429,12 @@ class Auth:
                     "Guest access token used for regular user"
                 )
 
-            return TokenLookupResult(
+            return create_requester(
                 user_id=user_id,
                 is_guest=True,
                 # all guests get the same device id
                 device_id=GUEST_DEVICE_ID,
+                authenticated_entity=user_id,
             )
         except (
             pymacaroons.exceptions.MacaroonException,
@@ -463,32 +457,33 @@ class Auth:
         request.requester = create_requester(service.sender, app_service=service)
         return service
 
-    async def is_server_admin(self, user: UserID) -> bool:
+    async def is_server_admin(self, requester: Requester) -> bool:
         """Check if the given user is a local server admin.
 
         Args:
-            user: user to check
+            requester: The user making the request, according to the access token.
 
         Returns:
             True if the user is an admin
         """
-        return await self.store.is_server_admin(user)
+        return await self.store.is_server_admin(requester.user)
 
-    async def check_can_change_room_list(self, room_id: str, user: UserID) -> bool:
+    async def check_can_change_room_list(
+        self, room_id: str, requester: Requester
+    ) -> bool:
         """Determine whether the user is allowed to edit the room's entry in the
         published room list.
 
         Args:
-            room_id
-            user
+            room_id: The room to check.
+            requester: The user making the request, according to the access token.
         """
 
-        is_admin = await self.is_server_admin(user)
+        is_admin = await self.is_server_admin(requester)
         if is_admin:
             return True
 
-        user_id = user.to_string()
-        await self.check_user_in_room(room_id, user_id)
+        await self.check_user_in_room(room_id, requester)
 
         # We currently require the user is a "moderator" in the room. We do this
         # by checking if they would (theoretically) be able to change the
@@ -507,7 +502,9 @@ class Auth:
         send_level = event_auth.get_send_level(
             EventTypes.CanonicalAlias, "", power_level_event
         )
-        user_level = event_auth.get_user_power_level(user_id, auth_events)
+        user_level = event_auth.get_user_power_level(
+            requester.user.to_string(), auth_events
+        )
 
         return user_level >= send_level
 
@@ -563,17 +560,18 @@ class Auth:
 
             return query_params[0].decode("ascii")
 
+    @trace
     async def check_user_in_room_or_world_readable(
-        self, room_id: str, user_id: str, allow_departed_users: bool = False
+        self, room_id: str, requester: Requester, allow_departed_users: bool = False
     ) -> Tuple[str, Optional[str]]:
         """Checks that the user is or was in the room or the room is world
         readable. If it isn't then an exception is raised.
 
         Args:
-            room_id: room to check
-            user_id: user to check
-            allow_departed_users: if True, accept users that were previously
-                members but have now departed
+            room_id: The room to check.
+            requester: The user making the request, according to the access token.
+            allow_departed_users: If True, accept users that were previously
+                members but have now departed.
 
         Returns:
             Resolves to the current membership of the user in the room and the
@@ -588,7 +586,7 @@ class Auth:
             #  * The user is a guest user, and has joined the room
             # else it will throw.
             return await self.check_user_in_room(
-                room_id, user_id, allow_departed_users=allow_departed_users
+                room_id, requester, allow_departed_users=allow_departed_users
             )
         except AuthError:
             visibility = await self._storage_controllers.state.get_current_state_event(
@@ -600,8 +598,9 @@ class Auth:
                 == HistoryVisibility.WORLD_READABLE
             ):
                 return Membership.JOIN, None
-            raise AuthError(
+            raise UnstableSpecAuthError(
                 403,
                 "User %s not in room %s, and room previews are disabled"
-                % (user_id, room_id),
+                % (requester.user, room_id),
+                errcode=Codes.NOT_JOINED,
             )
diff --git a/synapse/api/constants.py b/synapse/api/constants.py
index 2653764119..c73aea622a 100644
--- a/synapse/api/constants.py
+++ b/synapse/api/constants.py
@@ -216,11 +216,11 @@ class EventContentFields:
     MSC2716_HISTORICAL: Final = "org.matrix.msc2716.historical"
     # For "insertion" events to indicate what the next batch ID should be in
     # order to connect to it
-    MSC2716_NEXT_BATCH_ID: Final = "org.matrix.msc2716.next_batch_id"
+    MSC2716_NEXT_BATCH_ID: Final = "next_batch_id"
     # Used on "batch" events to indicate which insertion event it connects to
-    MSC2716_BATCH_ID: Final = "org.matrix.msc2716.batch_id"
+    MSC2716_BATCH_ID: Final = "batch_id"
     # For "marker" events
-    MSC2716_MARKER_INSERTION: Final = "org.matrix.msc2716.marker.insertion"
+    MSC2716_INSERTION_EVENT_REFERENCE: Final = "insertion_event_reference"
 
     # The authorising user for joining a restricted room.
     AUTHORISING_USER: Final = "join_authorised_via_users_server"
@@ -257,7 +257,8 @@ class GuestAccess:
 
 class ReceiptTypes:
     READ: Final = "m.read"
-    READ_PRIVATE: Final = "org.matrix.msc2285.read.private"
+    READ_PRIVATE: Final = "m.read.private"
+    UNSTABLE_READ_PRIVATE: Final = "org.matrix.msc2285.read.private"
     FULLY_READ: Final = "m.fully_read"
 
 
@@ -268,4 +269,4 @@ class PublicRoomsFilterFields:
     """
 
     GENERIC_SEARCH_TERM: Final = "generic_search_term"
-    ROOM_TYPES: Final = "org.matrix.msc3827.room_types"
+    ROOM_TYPES: Final = "room_types"
diff --git a/synapse/api/errors.py b/synapse/api/errors.py
index 1c74e131f2..e6dea89c6d 100644
--- a/synapse/api/errors.py
+++ b/synapse/api/errors.py
@@ -26,6 +26,7 @@ from twisted.web import http
 from synapse.util import json_decoder
 
 if typing.TYPE_CHECKING:
+    from synapse.config.homeserver import HomeServerConfig
     from synapse.types import JsonDict
 
 logger = logging.getLogger(__name__)
@@ -80,6 +81,12 @@ class Codes(str, Enum):
     INVALID_SIGNATURE = "M_INVALID_SIGNATURE"
     USER_DEACTIVATED = "M_USER_DEACTIVATED"
 
+    # Part of MSC3848
+    # https://github.com/matrix-org/matrix-spec-proposals/pull/3848
+    ALREADY_JOINED = "ORG.MATRIX.MSC3848.ALREADY_JOINED"
+    NOT_JOINED = "ORG.MATRIX.MSC3848.NOT_JOINED"
+    INSUFFICIENT_POWER = "ORG.MATRIX.MSC3848.INSUFFICIENT_POWER"
+
     # The account has been suspended on the server.
     # By opposition to `USER_DEACTIVATED`, this is a reversible measure
     # that can possibly be appealed and reverted.
@@ -167,7 +174,7 @@ class SynapseError(CodeMessageException):
         else:
             self._additional_fields = dict(additional_fields)
 
-    def error_dict(self) -> "JsonDict":
+    def error_dict(self, config: Optional["HomeServerConfig"]) -> "JsonDict":
         return cs_error(self.msg, self.errcode, **self._additional_fields)
 
 
@@ -213,7 +220,7 @@ class ConsentNotGivenError(SynapseError):
         )
         self._consent_uri = consent_uri
 
-    def error_dict(self) -> "JsonDict":
+    def error_dict(self, config: Optional["HomeServerConfig"]) -> "JsonDict":
         return cs_error(self.msg, self.errcode, consent_uri=self._consent_uri)
 
 
@@ -307,6 +314,37 @@ class AuthError(SynapseError):
         super().__init__(code, msg, errcode, additional_fields)
 
 
+class UnstableSpecAuthError(AuthError):
+    """An error raised when a new error code is being proposed to replace a previous one.
+    This error will return a "org.matrix.unstable.errcode" property with the new error code,
+    with the previous error code still being defined in the "errcode" property.
+
+    This error will include `org.matrix.msc3848.unstable.errcode` in the C-S error body.
+    """
+
+    def __init__(
+        self,
+        code: int,
+        msg: str,
+        errcode: str,
+        previous_errcode: str = Codes.FORBIDDEN,
+        additional_fields: Optional[dict] = None,
+    ):
+        self.previous_errcode = previous_errcode
+        super().__init__(code, msg, errcode, additional_fields)
+
+    def error_dict(self, config: Optional["HomeServerConfig"]) -> "JsonDict":
+        fields = {}
+        if config is not None and config.experimental.msc3848_enabled:
+            fields["org.matrix.msc3848.unstable.errcode"] = self.errcode
+        return cs_error(
+            self.msg,
+            self.previous_errcode,
+            **fields,
+            **self._additional_fields,
+        )
+
+
 class InvalidClientCredentialsError(SynapseError):
     """An error raised when there was a problem with the authorisation credentials
     in a client request.
@@ -338,8 +376,8 @@ class InvalidClientTokenError(InvalidClientCredentialsError):
         super().__init__(msg=msg, errcode="M_UNKNOWN_TOKEN")
         self._soft_logout = soft_logout
 
-    def error_dict(self) -> "JsonDict":
-        d = super().error_dict()
+    def error_dict(self, config: Optional["HomeServerConfig"]) -> "JsonDict":
+        d = super().error_dict(config)
         d["soft_logout"] = self._soft_logout
         return d
 
@@ -362,7 +400,7 @@ class ResourceLimitError(SynapseError):
         self.limit_type = limit_type
         super().__init__(code, msg, errcode=errcode)
 
-    def error_dict(self) -> "JsonDict":
+    def error_dict(self, config: Optional["HomeServerConfig"]) -> "JsonDict":
         return cs_error(
             self.msg,
             self.errcode,
@@ -397,7 +435,7 @@ class InvalidCaptchaError(SynapseError):
         super().__init__(code, msg, errcode)
         self.error_url = error_url
 
-    def error_dict(self) -> "JsonDict":
+    def error_dict(self, config: Optional["HomeServerConfig"]) -> "JsonDict":
         return cs_error(self.msg, self.errcode, error_url=self.error_url)
 
 
@@ -414,7 +452,7 @@ class LimitExceededError(SynapseError):
         super().__init__(code, msg, errcode)
         self.retry_after_ms = retry_after_ms
 
-    def error_dict(self) -> "JsonDict":
+    def error_dict(self, config: Optional["HomeServerConfig"]) -> "JsonDict":
         return cs_error(self.msg, self.errcode, retry_after_ms=self.retry_after_ms)
 
 
@@ -429,7 +467,7 @@ class RoomKeysVersionError(SynapseError):
         super().__init__(403, "Wrong room_keys version", Codes.WRONG_ROOM_KEYS_VERSION)
         self.current_version = current_version
 
-    def error_dict(self) -> "JsonDict":
+    def error_dict(self, config: Optional["HomeServerConfig"]) -> "JsonDict":
         return cs_error(self.msg, self.errcode, current_version=self.current_version)
 
 
@@ -469,7 +507,7 @@ class IncompatibleRoomVersionError(SynapseError):
 
         self._room_version = room_version
 
-    def error_dict(self) -> "JsonDict":
+    def error_dict(self, config: Optional["HomeServerConfig"]) -> "JsonDict":
         return cs_error(self.msg, self.errcode, room_version=self._room_version)
 
 
@@ -515,7 +553,7 @@ class UnredactedContentDeletedError(SynapseError):
         )
         self.content_keep_ms = content_keep_ms
 
-    def error_dict(self) -> "JsonDict":
+    def error_dict(self, config: Optional["HomeServerConfig"]) -> "JsonDict":
         extra = {}
         if self.content_keep_ms is not None:
             extra = {"fi.mau.msc2815.content_keep_ms": self.content_keep_ms}
diff --git a/synapse/api/ratelimiting.py b/synapse/api/ratelimiting.py
index f43965c1c8..044c7d4926 100644
--- a/synapse/api/ratelimiting.py
+++ b/synapse/api/ratelimiting.py
@@ -17,7 +17,7 @@ from collections import OrderedDict
 from typing import Hashable, Optional, Tuple
 
 from synapse.api.errors import LimitExceededError
-from synapse.config.ratelimiting import RateLimitConfig
+from synapse.config.ratelimiting import RatelimitSettings
 from synapse.storage.databases.main import DataStore
 from synapse.types import Requester
 from synapse.util import Clock
@@ -314,8 +314,8 @@ class RequestRatelimiter:
         self,
         store: DataStore,
         clock: Clock,
-        rc_message: RateLimitConfig,
-        rc_admin_redaction: Optional[RateLimitConfig],
+        rc_message: RatelimitSettings,
+        rc_admin_redaction: Optional[RatelimitSettings],
     ):
         self.store = store
         self.clock = clock
diff --git a/synapse/api/room_versions.py b/synapse/api/room_versions.py
index 00e81b3afc..a0e4ab6db6 100644
--- a/synapse/api/room_versions.py
+++ b/synapse/api/room_versions.py
@@ -269,24 +269,6 @@ class RoomVersions:
         msc3787_knock_restricted_join_rule=False,
         msc3667_int_only_power_levels=False,
     )
-    MSC2716v3 = RoomVersion(
-        "org.matrix.msc2716v3",
-        RoomDisposition.UNSTABLE,
-        EventFormatVersions.V3,
-        StateResolutionVersions.V2,
-        enforce_key_validity=True,
-        special_case_aliases_auth=False,
-        strict_canonicaljson=True,
-        limit_notifications_power_levels=True,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=False,
-        msc3375_redaction_rules=False,
-        msc2403_knocking=True,
-        msc2716_historical=True,
-        msc2716_redactions=True,
-        msc3787_knock_restricted_join_rule=False,
-        msc3667_int_only_power_levels=False,
-    )
     MSC3787 = RoomVersion(
         "org.matrix.msc3787",
         RoomDisposition.UNSTABLE,
@@ -323,6 +305,24 @@ class RoomVersions:
         msc3787_knock_restricted_join_rule=True,
         msc3667_int_only_power_levels=True,
     )
+    MSC2716v4 = RoomVersion(
+        "org.matrix.msc2716v4",
+        RoomDisposition.UNSTABLE,
+        EventFormatVersions.V3,
+        StateResolutionVersions.V2,
+        enforce_key_validity=True,
+        special_case_aliases_auth=False,
+        strict_canonicaljson=True,
+        limit_notifications_power_levels=True,
+        msc2176_redaction_rules=False,
+        msc3083_join_rules=False,
+        msc3375_redaction_rules=False,
+        msc2403_knocking=True,
+        msc2716_historical=True,
+        msc2716_redactions=True,
+        msc3787_knock_restricted_join_rule=False,
+        msc3667_int_only_power_levels=False,
+    )
 
 
 KNOWN_ROOM_VERSIONS: Dict[str, RoomVersion] = {
@@ -338,9 +338,9 @@ KNOWN_ROOM_VERSIONS: Dict[str, RoomVersion] = {
         RoomVersions.V7,
         RoomVersions.V8,
         RoomVersions.V9,
-        RoomVersions.MSC2716v3,
         RoomVersions.MSC3787,
         RoomVersions.V10,
+        RoomVersions.MSC2716v4,
     )
 }
 
diff --git a/synapse/app/admin_cmd.py b/synapse/app/admin_cmd.py
index 87f82bd9a5..8a583d3ec6 100644
--- a/synapse/app/admin_cmd.py
+++ b/synapse/app/admin_cmd.py
@@ -28,19 +28,22 @@ from synapse.config.homeserver import HomeServerConfig
 from synapse.config.logger import setup_logging
 from synapse.events import EventBase
 from synapse.handlers.admin import ExfiltrationWriter
-from synapse.replication.slave.storage._base import BaseSlavedStore
-from synapse.replication.slave.storage.account_data import SlavedAccountDataStore
-from synapse.replication.slave.storage.appservice import SlavedApplicationServiceStore
-from synapse.replication.slave.storage.deviceinbox import SlavedDeviceInboxStore
 from synapse.replication.slave.storage.devices import SlavedDeviceStore
 from synapse.replication.slave.storage.events import SlavedEventStore
 from synapse.replication.slave.storage.filtering import SlavedFilteringStore
 from synapse.replication.slave.storage.push_rule import SlavedPushRuleStore
-from synapse.replication.slave.storage.receipts import SlavedReceiptsStore
-from synapse.replication.slave.storage.registration import SlavedRegistrationStore
 from synapse.server import HomeServer
 from synapse.storage.database import DatabasePool, LoggingDatabaseConnection
+from synapse.storage.databases.main.account_data import AccountDataWorkerStore
+from synapse.storage.databases.main.appservice import (
+    ApplicationServiceTransactionWorkerStore,
+    ApplicationServiceWorkerStore,
+)
+from synapse.storage.databases.main.deviceinbox import DeviceInboxWorkerStore
+from synapse.storage.databases.main.receipts import ReceiptsWorkerStore
+from synapse.storage.databases.main.registration import RegistrationWorkerStore
 from synapse.storage.databases.main.room import RoomWorkerStore
+from synapse.storage.databases.main.tags import TagsWorkerStore
 from synapse.types import StateMap
 from synapse.util import SYNAPSE_VERSION
 from synapse.util.logcontext import LoggingContext
@@ -49,16 +52,17 @@ logger = logging.getLogger("synapse.app.admin_cmd")
 
 
 class AdminCmdSlavedStore(
-    SlavedReceiptsStore,
-    SlavedAccountDataStore,
-    SlavedApplicationServiceStore,
-    SlavedRegistrationStore,
     SlavedFilteringStore,
-    SlavedDeviceInboxStore,
     SlavedDeviceStore,
     SlavedPushRuleStore,
     SlavedEventStore,
-    BaseSlavedStore,
+    TagsWorkerStore,
+    DeviceInboxWorkerStore,
+    AccountDataWorkerStore,
+    ApplicationServiceTransactionWorkerStore,
+    ApplicationServiceWorkerStore,
+    RegistrationWorkerStore,
+    ReceiptsWorkerStore,
     RoomWorkerStore,
 ):
     def __init__(
diff --git a/synapse/app/generic_worker.py b/synapse/app/generic_worker.py
index 4a987fb759..30e21d9707 100644
--- a/synapse/app/generic_worker.py
+++ b/synapse/app/generic_worker.py
@@ -48,20 +48,12 @@ from synapse.http.site import SynapseRequest, SynapseSite
 from synapse.logging.context import LoggingContext
 from synapse.metrics import METRICS_PREFIX, MetricsResource, RegistryProxy
 from synapse.replication.http import REPLICATION_PREFIX, ReplicationRestResource
-from synapse.replication.slave.storage._base import BaseSlavedStore
-from synapse.replication.slave.storage.account_data import SlavedAccountDataStore
-from synapse.replication.slave.storage.appservice import SlavedApplicationServiceStore
-from synapse.replication.slave.storage.deviceinbox import SlavedDeviceInboxStore
 from synapse.replication.slave.storage.devices import SlavedDeviceStore
-from synapse.replication.slave.storage.directory import DirectoryStore
 from synapse.replication.slave.storage.events import SlavedEventStore
 from synapse.replication.slave.storage.filtering import SlavedFilteringStore
 from synapse.replication.slave.storage.keys import SlavedKeyStore
-from synapse.replication.slave.storage.profile import SlavedProfileStore
 from synapse.replication.slave.storage.push_rule import SlavedPushRuleStore
 from synapse.replication.slave.storage.pushers import SlavedPusherStore
-from synapse.replication.slave.storage.receipts import SlavedReceiptsStore
-from synapse.replication.slave.storage.registration import SlavedRegistrationStore
 from synapse.rest.admin import register_servlets_for_media_repo
 from synapse.rest.client import (
     account_data,
@@ -100,8 +92,15 @@ from synapse.rest.key.v2 import KeyApiV2Resource
 from synapse.rest.synapse.client import build_synapse_client_resource_tree
 from synapse.rest.well_known import well_known_resource
 from synapse.server import HomeServer
+from synapse.storage.databases.main.account_data import AccountDataWorkerStore
+from synapse.storage.databases.main.appservice import (
+    ApplicationServiceTransactionWorkerStore,
+    ApplicationServiceWorkerStore,
+)
 from synapse.storage.databases.main.censor_events import CensorEventsStore
 from synapse.storage.databases.main.client_ips import ClientIpWorkerStore
+from synapse.storage.databases.main.deviceinbox import DeviceInboxWorkerStore
+from synapse.storage.databases.main.directory import DirectoryWorkerStore
 from synapse.storage.databases.main.e2e_room_keys import EndToEndRoomKeyStore
 from synapse.storage.databases.main.lock import LockStore
 from synapse.storage.databases.main.media_repository import MediaRepositoryStore
@@ -110,11 +109,15 @@ from synapse.storage.databases.main.monthly_active_users import (
     MonthlyActiveUsersWorkerStore,
 )
 from synapse.storage.databases.main.presence import PresenceStore
+from synapse.storage.databases.main.profile import ProfileWorkerStore
+from synapse.storage.databases.main.receipts import ReceiptsWorkerStore
+from synapse.storage.databases.main.registration import RegistrationWorkerStore
 from synapse.storage.databases.main.room import RoomWorkerStore
 from synapse.storage.databases.main.room_batch import RoomBatchStore
 from synapse.storage.databases.main.search import SearchStore
 from synapse.storage.databases.main.session import SessionStore
 from synapse.storage.databases.main.stats import StatsStore
+from synapse.storage.databases.main.tags import TagsWorkerStore
 from synapse.storage.databases.main.transactions import TransactionWorkerStore
 from synapse.storage.databases.main.ui_auth import UIAuthWorkerStore
 from synapse.storage.databases.main.user_directory import UserDirectoryStore
@@ -227,11 +230,11 @@ class GenericWorkerSlavedStore(
     UIAuthWorkerStore,
     EndToEndRoomKeyStore,
     PresenceStore,
-    SlavedDeviceInboxStore,
+    DeviceInboxWorkerStore,
     SlavedDeviceStore,
-    SlavedReceiptsStore,
     SlavedPushRuleStore,
-    SlavedAccountDataStore,
+    TagsWorkerStore,
+    AccountDataWorkerStore,
     SlavedPusherStore,
     CensorEventsStore,
     ClientIpWorkerStore,
@@ -239,19 +242,20 @@ class GenericWorkerSlavedStore(
     SlavedKeyStore,
     RoomWorkerStore,
     RoomBatchStore,
-    DirectoryStore,
-    SlavedApplicationServiceStore,
-    SlavedRegistrationStore,
-    SlavedProfileStore,
+    DirectoryWorkerStore,
+    ApplicationServiceTransactionWorkerStore,
+    ApplicationServiceWorkerStore,
+    ProfileWorkerStore,
     SlavedFilteringStore,
     MonthlyActiveUsersWorkerStore,
     MediaRepositoryStore,
     ServerMetricsStore,
+    ReceiptsWorkerStore,
+    RegistrationWorkerStore,
     SearchStore,
     TransactionWorkerStore,
     LockStore,
     SessionStore,
-    BaseSlavedStore,
 ):
     # Properties that multiple storage classes define. Tell mypy what the
     # expected type is.
@@ -437,6 +441,13 @@ def start(config_options: List[str]) -> None:
         "synapse.app.user_dir",
     )
 
+    if config.experimental.faster_joins_enabled:
+        raise ConfigError(
+            "You have enabled the experimental `faster_joins` config option, but it is "
+            "not compatible with worker deployments yet. Please disable `faster_joins` "
+            "or run Synapse as a single process deployment instead."
+        )
+
     synapse.events.USE_FROZEN_DICTS = config.server.use_frozen_dicts
     synapse.util.caches.TRACK_MEMORY_USAGE = config.caches.track_memory_usage
 
diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py
index 6bafa7d3f3..68993d91a9 100644
--- a/synapse/app/homeserver.py
+++ b/synapse/app/homeserver.py
@@ -219,7 +219,10 @@ class SynapseHomeServer(HomeServer):
             resources.update({"/_matrix/consent": consent_resource})
 
         if name == "federation":
-            resources.update({FEDERATION_PREFIX: TransportLayerServer(self)})
+            federation_resource: Resource = TransportLayerServer(self)
+            if compress:
+                federation_resource = gz_wrap(federation_resource)
+            resources.update({FEDERATION_PREFIX: federation_resource})
 
         if name == "openid":
             resources.update(
diff --git a/synapse/config/account_validity.py b/synapse/config/account_validity.py
index d1335e77cd..b3972ede96 100644
--- a/synapse/config/account_validity.py
+++ b/synapse/config/account_validity.py
@@ -23,7 +23,7 @@ LEGACY_TEMPLATE_DIR_WARNING = """
 This server's configuration file is using the deprecated 'template_dir' setting in the
 'account_validity' section. Support for this setting has been deprecated and will be
 removed in a future version of Synapse. Server admins should instead use the new
-'custom_templates_directory' setting documented here:
+'custom_template_directory' setting documented here:
 https://matrix-org.github.io/synapse/latest/templates.html
 ---------------------------------------------------------------------------------------"""
 
diff --git a/synapse/config/emailconfig.py b/synapse/config/emailconfig.py
index 3ead80d985..a3af35b7c4 100644
--- a/synapse/config/emailconfig.py
+++ b/synapse/config/emailconfig.py
@@ -52,7 +52,7 @@ LEGACY_TEMPLATE_DIR_WARNING = """
 This server's configuration file is using the deprecated 'template_dir' setting in the
 'email' section. Support for this setting has been deprecated and will be removed in a
 future version of Synapse. Server admins should instead use the new
-'custom_templates_directory' setting documented here:
+'custom_template_directory' setting documented here:
 https://matrix-org.github.io/synapse/latest/templates.html
 ---------------------------------------------------------------------------------------"""
 
@@ -85,14 +85,19 @@ class EmailConfig(Config):
         if email_config is None:
             email_config = {}
 
+        self.force_tls = email_config.get("force_tls", False)
         self.email_smtp_host = email_config.get("smtp_host", "localhost")
-        self.email_smtp_port = email_config.get("smtp_port", 25)
+        self.email_smtp_port = email_config.get(
+            "smtp_port", 465 if self.force_tls else 25
+        )
         self.email_smtp_user = email_config.get("smtp_user", None)
         self.email_smtp_pass = email_config.get("smtp_pass", None)
         self.require_transport_security = email_config.get(
             "require_transport_security", False
         )
         self.enable_smtp_tls = email_config.get("enable_tls", True)
+        if self.force_tls and not self.enable_smtp_tls:
+            raise ConfigError("email.force_tls requires email.enable_tls to be true")
         if self.require_transport_security and not self.enable_smtp_tls:
             raise ConfigError(
                 "email.require_transport_security requires email.enable_tls to be true"
diff --git a/synapse/config/experimental.py b/synapse/config/experimental.py
index ee443cea00..c1ff417539 100644
--- a/synapse/config/experimental.py
+++ b/synapse/config/experimental.py
@@ -32,7 +32,7 @@ class ExperimentalConfig(Config):
         # MSC2716 (importing historical messages)
         self.msc2716_enabled: bool = experimental.get("msc2716_enabled", False)
 
-        # MSC2285 (private read receipts)
+        # MSC2285 (unstable private read receipts)
         self.msc2285_enabled: bool = experimental.get("msc2285_enabled", False)
 
         # MSC3244 (room version capabilities)
@@ -88,5 +88,8 @@ class ExperimentalConfig(Config):
         # MSC3715: dir param on /relations.
         self.msc3715_enabled: bool = experimental.get("msc3715_enabled", False)
 
-        # MSC3827: Filtering of /publicRooms by room type
-        self.msc3827_enabled: bool = experimental.get("msc3827_enabled", False)
+        # MSC3848: Introduce errcodes for specific event sending failures
+        self.msc3848_enabled: bool = experimental.get("msc3848_enabled", False)
+
+        # MSC3852: Expose last seen user agent field on /_matrix/client/v3/devices.
+        self.msc3852_enabled: bool = experimental.get("msc3852_enabled", False)
diff --git a/synapse/config/ratelimiting.py b/synapse/config/ratelimiting.py
index 5a91917b4a..1ed001e105 100644
--- a/synapse/config/ratelimiting.py
+++ b/synapse/config/ratelimiting.py
@@ -21,7 +21,7 @@ from synapse.types import JsonDict
 from ._base import Config
 
 
-class RateLimitConfig:
+class RatelimitSettings:
     def __init__(
         self,
         config: Dict[str, float],
@@ -34,7 +34,7 @@ class RateLimitConfig:
 
 
 @attr.s(auto_attribs=True)
-class FederationRateLimitConfig:
+class FederationRatelimitSettings:
     window_size: int = 1000
     sleep_limit: int = 10
     sleep_delay: int = 500
@@ -50,11 +50,11 @@ class RatelimitConfig(Config):
         # Load the new-style messages config if it exists. Otherwise fall back
         # to the old method.
         if "rc_message" in config:
-            self.rc_message = RateLimitConfig(
+            self.rc_message = RatelimitSettings(
                 config["rc_message"], defaults={"per_second": 0.2, "burst_count": 10.0}
             )
         else:
-            self.rc_message = RateLimitConfig(
+            self.rc_message = RatelimitSettings(
                 {
                     "per_second": config.get("rc_messages_per_second", 0.2),
                     "burst_count": config.get("rc_message_burst_count", 10.0),
@@ -64,9 +64,9 @@ class RatelimitConfig(Config):
         # Load the new-style federation config, if it exists. Otherwise, fall
         # back to the old method.
         if "rc_federation" in config:
-            self.rc_federation = FederationRateLimitConfig(**config["rc_federation"])
+            self.rc_federation = FederationRatelimitSettings(**config["rc_federation"])
         else:
-            self.rc_federation = FederationRateLimitConfig(
+            self.rc_federation = FederationRatelimitSettings(
                 **{
                     k: v
                     for k, v in {
@@ -80,17 +80,17 @@ class RatelimitConfig(Config):
                 }
             )
 
-        self.rc_registration = RateLimitConfig(config.get("rc_registration", {}))
+        self.rc_registration = RatelimitSettings(config.get("rc_registration", {}))
 
-        self.rc_registration_token_validity = RateLimitConfig(
+        self.rc_registration_token_validity = RatelimitSettings(
             config.get("rc_registration_token_validity", {}),
             defaults={"per_second": 0.1, "burst_count": 5},
         )
 
         rc_login_config = config.get("rc_login", {})
-        self.rc_login_address = RateLimitConfig(rc_login_config.get("address", {}))
-        self.rc_login_account = RateLimitConfig(rc_login_config.get("account", {}))
-        self.rc_login_failed_attempts = RateLimitConfig(
+        self.rc_login_address = RatelimitSettings(rc_login_config.get("address", {}))
+        self.rc_login_account = RatelimitSettings(rc_login_config.get("account", {}))
+        self.rc_login_failed_attempts = RatelimitSettings(
             rc_login_config.get("failed_attempts", {})
         )
 
@@ -101,20 +101,20 @@ class RatelimitConfig(Config):
         rc_admin_redaction = config.get("rc_admin_redaction")
         self.rc_admin_redaction = None
         if rc_admin_redaction:
-            self.rc_admin_redaction = RateLimitConfig(rc_admin_redaction)
+            self.rc_admin_redaction = RatelimitSettings(rc_admin_redaction)
 
-        self.rc_joins_local = RateLimitConfig(
+        self.rc_joins_local = RatelimitSettings(
             config.get("rc_joins", {}).get("local", {}),
             defaults={"per_second": 0.1, "burst_count": 10},
         )
-        self.rc_joins_remote = RateLimitConfig(
+        self.rc_joins_remote = RatelimitSettings(
             config.get("rc_joins", {}).get("remote", {}),
             defaults={"per_second": 0.01, "burst_count": 10},
         )
 
         # Track the rate of joins to a given room. If there are too many, temporarily
         # prevent local joins and remote joins via this server.
-        self.rc_joins_per_room = RateLimitConfig(
+        self.rc_joins_per_room = RatelimitSettings(
             config.get("rc_joins_per_room", {}),
             defaults={"per_second": 1, "burst_count": 10},
         )
@@ -124,31 +124,31 @@ class RatelimitConfig(Config):
         # * For requests received over federation this is keyed by the origin.
         #
         # Note that this isn't exposed in the configuration as it is obscure.
-        self.rc_key_requests = RateLimitConfig(
+        self.rc_key_requests = RatelimitSettings(
             config.get("rc_key_requests", {}),
             defaults={"per_second": 20, "burst_count": 100},
         )
 
-        self.rc_3pid_validation = RateLimitConfig(
+        self.rc_3pid_validation = RatelimitSettings(
             config.get("rc_3pid_validation") or {},
             defaults={"per_second": 0.003, "burst_count": 5},
         )
 
-        self.rc_invites_per_room = RateLimitConfig(
+        self.rc_invites_per_room = RatelimitSettings(
             config.get("rc_invites", {}).get("per_room", {}),
             defaults={"per_second": 0.3, "burst_count": 10},
         )
-        self.rc_invites_per_user = RateLimitConfig(
+        self.rc_invites_per_user = RatelimitSettings(
             config.get("rc_invites", {}).get("per_user", {}),
             defaults={"per_second": 0.003, "burst_count": 5},
         )
 
-        self.rc_invites_per_issuer = RateLimitConfig(
+        self.rc_invites_per_issuer = RatelimitSettings(
             config.get("rc_invites", {}).get("per_issuer", {}),
             defaults={"per_second": 0.3, "burst_count": 10},
         )
 
-        self.rc_third_party_invite = RateLimitConfig(
+        self.rc_third_party_invite = RatelimitSettings(
             config.get("rc_third_party_invite", {}),
             defaults={
                 "per_second": self.rc_message.per_second,
diff --git a/synapse/config/registration.py b/synapse/config/registration.py
index 685a0423c5..a888d976f2 100644
--- a/synapse/config/registration.py
+++ b/synapse/config/registration.py
@@ -60,7 +60,6 @@ class RegistrationConfig(Config):
         account_threepid_delegates = config.get("account_threepid_delegates") or {}
         if "email" in account_threepid_delegates:
             raise ConfigError(NO_EMAIL_DELEGATE_ERROR)
-        # self.account_threepid_delegate_email = account_threepid_delegates.get("email")
         self.account_threepid_delegate_msisdn = account_threepid_delegates.get("msisdn")
         self.default_identity_server = config.get("default_identity_server")
         self.allow_guest_access = config.get("allow_guest_access", False)
diff --git a/synapse/config/sso.py b/synapse/config/sso.py
index 2178cbf983..a452cc3a49 100644
--- a/synapse/config/sso.py
+++ b/synapse/config/sso.py
@@ -26,7 +26,7 @@ LEGACY_TEMPLATE_DIR_WARNING = """
 This server's configuration file is using the deprecated 'template_dir' setting in the
 'sso' section. Support for this setting has been deprecated and will be removed in a
 future version of Synapse. Server admins should instead use the new
-'custom_templates_directory' setting documented here:
+'custom_template_directory' setting documented here:
 https://matrix-org.github.io/synapse/latest/templates.html
 ---------------------------------------------------------------------------------------"""
 
diff --git a/synapse/crypto/event_signing.py b/synapse/crypto/event_signing.py
index 7520647d1e..23b799ac32 100644
--- a/synapse/crypto/event_signing.py
+++ b/synapse/crypto/event_signing.py
@@ -28,6 +28,7 @@ from synapse.api.errors import Codes, SynapseError
 from synapse.api.room_versions import RoomVersion
 from synapse.events import EventBase
 from synapse.events.utils import prune_event, prune_event_dict
+from synapse.logging.opentracing import trace
 from synapse.types import JsonDict
 
 logger = logging.getLogger(__name__)
@@ -35,6 +36,7 @@ logger = logging.getLogger(__name__)
 Hasher = Callable[[bytes], "hashlib._Hash"]
 
 
+@trace
 def check_event_content_hash(
     event: EventBase, hash_algorithm: Hasher = hashlib.sha256
 ) -> bool:
diff --git a/synapse/event_auth.py b/synapse/event_auth.py
index 965cb265da..389b0c5d53 100644
--- a/synapse/event_auth.py
+++ b/synapse/event_auth.py
@@ -30,7 +30,13 @@ from synapse.api.constants import (
     JoinRules,
     Membership,
 )
-from synapse.api.errors import AuthError, EventSizeError, SynapseError
+from synapse.api.errors import (
+    AuthError,
+    Codes,
+    EventSizeError,
+    SynapseError,
+    UnstableSpecAuthError,
+)
 from synapse.api.room_versions import (
     KNOWN_ROOM_VERSIONS,
     EventFormatVersions,
@@ -291,7 +297,11 @@ def check_state_dependent_auth_rules(
         invite_level = get_named_level(auth_dict, "invite", 0)
 
         if user_level < invite_level:
-            raise AuthError(403, "You don't have permission to invite users")
+            raise UnstableSpecAuthError(
+                403,
+                "You don't have permission to invite users",
+                errcode=Codes.INSUFFICIENT_POWER,
+            )
         else:
             logger.debug("Allowing! %s", event)
             return
@@ -474,7 +484,11 @@ def _is_membership_change_allowed(
             return
 
         if not caller_in_room:  # caller isn't joined
-            raise AuthError(403, "%s not in room %s." % (event.user_id, event.room_id))
+            raise UnstableSpecAuthError(
+                403,
+                "%s not in room %s." % (event.user_id, event.room_id),
+                errcode=Codes.NOT_JOINED,
+            )
 
     if Membership.INVITE == membership:
         # TODO (erikj): We should probably handle this more intelligently
@@ -484,10 +498,18 @@ def _is_membership_change_allowed(
         if target_banned:
             raise AuthError(403, "%s is banned from the room" % (target_user_id,))
         elif target_in_room:  # the target is already in the room.
-            raise AuthError(403, "%s is already in the room." % target_user_id)
+            raise UnstableSpecAuthError(
+                403,
+                "%s is already in the room." % target_user_id,
+                errcode=Codes.ALREADY_JOINED,
+            )
         else:
             if user_level < invite_level:
-                raise AuthError(403, "You don't have permission to invite users")
+                raise UnstableSpecAuthError(
+                    403,
+                    "You don't have permission to invite users",
+                    errcode=Codes.INSUFFICIENT_POWER,
+                )
     elif Membership.JOIN == membership:
         # Joins are valid iff caller == target and:
         # * They are not banned.
@@ -549,15 +571,27 @@ def _is_membership_change_allowed(
     elif Membership.LEAVE == membership:
         # TODO (erikj): Implement kicks.
         if target_banned and user_level < ban_level:
-            raise AuthError(403, "You cannot unban user %s." % (target_user_id,))
+            raise UnstableSpecAuthError(
+                403,
+                "You cannot unban user %s." % (target_user_id,),
+                errcode=Codes.INSUFFICIENT_POWER,
+            )
         elif target_user_id != event.user_id:
             kick_level = get_named_level(auth_events, "kick", 50)
 
             if user_level < kick_level or user_level <= target_level:
-                raise AuthError(403, "You cannot kick user %s." % target_user_id)
+                raise UnstableSpecAuthError(
+                    403,
+                    "You cannot kick user %s." % target_user_id,
+                    errcode=Codes.INSUFFICIENT_POWER,
+                )
     elif Membership.BAN == membership:
         if user_level < ban_level or user_level <= target_level:
-            raise AuthError(403, "You don't have permission to ban")
+            raise UnstableSpecAuthError(
+                403,
+                "You don't have permission to ban",
+                errcode=Codes.INSUFFICIENT_POWER,
+            )
     elif room_version.msc2403_knocking and Membership.KNOCK == membership:
         if join_rule != JoinRules.KNOCK and (
             not room_version.msc3787_knock_restricted_join_rule
@@ -567,7 +601,11 @@ def _is_membership_change_allowed(
         elif target_user_id != event.user_id:
             raise AuthError(403, "You cannot knock for other users")
         elif target_in_room:
-            raise AuthError(403, "You cannot knock on a room you are already in")
+            raise UnstableSpecAuthError(
+                403,
+                "You cannot knock on a room you are already in",
+                errcode=Codes.ALREADY_JOINED,
+            )
         elif caller_invited:
             raise AuthError(403, "You are already invited to this room")
         elif target_banned:
@@ -638,10 +676,11 @@ def _can_send_event(event: "EventBase", auth_events: StateMap["EventBase"]) -> b
     user_level = get_user_power_level(event.user_id, auth_events)
 
     if user_level < send_level:
-        raise AuthError(
+        raise UnstableSpecAuthError(
             403,
             "You don't have permission to post that to the room. "
             + "user_level (%d) < send_level (%d)" % (user_level, send_level),
+            errcode=Codes.INSUFFICIENT_POWER,
         )
 
     # Check state_key
@@ -716,9 +755,10 @@ def check_historical(
     historical_level = get_named_level(auth_events, "historical", 100)
 
     if user_level < historical_level:
-        raise AuthError(
+        raise UnstableSpecAuthError(
             403,
             'You don\'t have permission to send send historical related events ("insertion", "batch", and "marker")',
+            errcode=Codes.INSUFFICIENT_POWER,
         )
 
 
diff --git a/synapse/events/snapshot.py b/synapse/events/snapshot.py
index b700cbbfa1..d3c8083e4a 100644
--- a/synapse/events/snapshot.py
+++ b/synapse/events/snapshot.py
@@ -11,11 +11,10 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from typing import TYPE_CHECKING, List, Optional, Tuple, Union
+from typing import TYPE_CHECKING, List, Optional, Tuple
 
 import attr
 from frozendict import frozendict
-from typing_extensions import Literal
 
 from synapse.appservice import ApplicationService
 from synapse.events import EventBase
@@ -33,7 +32,7 @@ class EventContext:
     Holds information relevant to persisting an event
 
     Attributes:
-        rejected: A rejection reason if the event was rejected, else False
+        rejected: A rejection reason if the event was rejected, else None
 
         _state_group: The ID of the state group for this event. Note that state events
             are persisted with a state group which includes the new event, so this is
@@ -85,7 +84,7 @@ class EventContext:
     """
 
     _storage: "StorageControllers"
-    rejected: Union[Literal[False], str] = False
+    rejected: Optional[str] = None
     _state_group: Optional[int] = None
     state_group_before_event: Optional[int] = None
     _state_delta_due_to_event: Optional[StateMap[str]] = None
diff --git a/synapse/events/spamcheck.py b/synapse/events/spamcheck.py
index 4a3bfb38f1..623a2c71ea 100644
--- a/synapse/events/spamcheck.py
+++ b/synapse/events/spamcheck.py
@@ -32,6 +32,7 @@ from typing_extensions import Literal
 
 import synapse
 from synapse.api.errors import Codes
+from synapse.logging.opentracing import trace
 from synapse.rest.media.v1._base import FileInfo
 from synapse.rest.media.v1.media_storage import ReadableFileWrapper
 from synapse.spam_checker_api import RegistrationBehaviour
@@ -378,6 +379,7 @@ class SpamChecker:
         if check_media_file_for_spam is not None:
             self._check_media_file_for_spam_callbacks.append(check_media_file_for_spam)
 
+    @trace
     async def check_event_for_spam(
         self, event: "synapse.events.EventBase"
     ) -> Union[Tuple[Codes, JsonDict], str]:
diff --git a/synapse/events/utils.py b/synapse/events/utils.py
index ac91c5eb57..71853caad8 100644
--- a/synapse/events/utils.py
+++ b/synapse/events/utils.py
@@ -161,7 +161,7 @@ def prune_event_dict(room_version: RoomVersion, event_dict: JsonDict) -> JsonDic
     elif room_version.msc2716_redactions and event_type == EventTypes.MSC2716_BATCH:
         add_fields(EventContentFields.MSC2716_BATCH_ID)
     elif room_version.msc2716_redactions and event_type == EventTypes.MSC2716_MARKER:
-        add_fields(EventContentFields.MSC2716_MARKER_INSERTION)
+        add_fields(EventContentFields.MSC2716_INSERTION_EVENT_REFERENCE)
 
     allowed_fields = {k: v for k, v in event_dict.items() if k in allowed_keys}
 
diff --git a/synapse/federation/federation_base.py b/synapse/federation/federation_base.py
index 2522bf78fc..4269a98db2 100644
--- a/synapse/federation/federation_base.py
+++ b/synapse/federation/federation_base.py
@@ -23,6 +23,7 @@ from synapse.crypto.keyring import Keyring
 from synapse.events import EventBase, make_event_from_dict
 from synapse.events.utils import prune_event, validate_canonicaljson
 from synapse.http.servlet import assert_params_in_dict
+from synapse.logging.opentracing import log_kv, trace
 from synapse.types import JsonDict, get_domain_from_id
 
 if TYPE_CHECKING:
@@ -55,6 +56,7 @@ class FederationBase:
         self._clock = hs.get_clock()
         self._storage_controllers = hs.get_storage_controllers()
 
+    @trace
     async def _check_sigs_and_hash(
         self, room_version: RoomVersion, pdu: EventBase
     ) -> EventBase:
@@ -97,17 +99,36 @@ class FederationBase:
                     "Event %s seems to have been redacted; using our redacted copy",
                     pdu.event_id,
                 )
+                log_kv(
+                    {
+                        "message": "Event seems to have been redacted; using our redacted copy",
+                        "event_id": pdu.event_id,
+                    }
+                )
             else:
                 logger.warning(
                     "Event %s content has been tampered, redacting",
                     pdu.event_id,
                 )
+                log_kv(
+                    {
+                        "message": "Event content has been tampered, redacting",
+                        "event_id": pdu.event_id,
+                    }
+                )
             return redacted_event
 
         spam_check = await self.spam_checker.check_event_for_spam(pdu)
 
         if spam_check != self.spam_checker.NOT_SPAM:
             logger.warning("Event contains spam, soft-failing %s", pdu.event_id)
+            log_kv(
+                {
+                    "message": "Event contains spam, redacting (to save disk space) "
+                    "as well as soft-failing (to stop using the event in prev_events)",
+                    "event_id": pdu.event_id,
+                }
+            )
             # we redact (to save disk space) as well as soft-failing (to stop
             # using the event in prev_events).
             redacted_event = prune_event(pdu)
@@ -117,6 +138,7 @@ class FederationBase:
         return pdu
 
 
+@trace
 async def _check_sigs_on_pdu(
     keyring: Keyring, room_version: RoomVersion, pdu: EventBase
 ) -> None:
diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py
index 842f5327c2..7ee2974bb1 100644
--- a/synapse/federation/federation_client.py
+++ b/synapse/federation/federation_client.py
@@ -61,6 +61,7 @@ from synapse.federation.federation_base import (
 )
 from synapse.federation.transport.client import SendJoinResponse
 from synapse.http.types import QueryParams
+from synapse.logging.opentracing import SynapseTags, log_kv, set_tag, tag_args, trace
 from synapse.types import JsonDict, UserID, get_domain_from_id
 from synapse.util.async_helpers import concurrently_execute
 from synapse.util.caches.expiringcache import ExpiringCache
@@ -233,6 +234,8 @@ class FederationClient(FederationBase):
             destination, content, timeout
         )
 
+    @trace
+    @tag_args
     async def backfill(
         self, dest: str, room_id: str, limit: int, extremities: Collection[str]
     ) -> Optional[List[EventBase]]:
@@ -335,6 +338,8 @@ class FederationClient(FederationBase):
 
         return None
 
+    @trace
+    @tag_args
     async def get_pdu(
         self,
         destinations: Iterable[str],
@@ -403,9 +408,9 @@ class FederationClient(FederationBase):
                         # Prime the cache
                         self._get_pdu_cache[event.event_id] = event
 
-                        # FIXME: We should add a `break` here to avoid calling every
-                        # destination after we already found a PDU (will follow-up
-                        # in a separate PR)
+                        # Now that we have an event, we can break out of this
+                        # loop and stop asking other destinations.
+                        break
 
                 except SynapseError as e:
                     logger.info(
@@ -446,6 +451,8 @@ class FederationClient(FederationBase):
 
         return event_copy
 
+    @trace
+    @tag_args
     async def get_room_state_ids(
         self, destination: str, room_id: str, event_id: str
     ) -> Tuple[List[str], List[str]]:
@@ -465,6 +472,23 @@ class FederationClient(FederationBase):
         state_event_ids = result["pdu_ids"]
         auth_event_ids = result.get("auth_chain_ids", [])
 
+        set_tag(
+            SynapseTags.RESULT_PREFIX + "state_event_ids",
+            str(state_event_ids),
+        )
+        set_tag(
+            SynapseTags.RESULT_PREFIX + "state_event_ids.length",
+            str(len(state_event_ids)),
+        )
+        set_tag(
+            SynapseTags.RESULT_PREFIX + "auth_event_ids",
+            str(auth_event_ids),
+        )
+        set_tag(
+            SynapseTags.RESULT_PREFIX + "auth_event_ids.length",
+            str(len(auth_event_ids)),
+        )
+
         if not isinstance(state_event_ids, list) or not isinstance(
             auth_event_ids, list
         ):
@@ -472,6 +496,8 @@ class FederationClient(FederationBase):
 
         return state_event_ids, auth_event_ids
 
+    @trace
+    @tag_args
     async def get_room_state(
         self,
         destination: str,
@@ -531,6 +557,7 @@ class FederationClient(FederationBase):
 
         return valid_state_events, valid_auth_events
 
+    @trace
     async def _check_sigs_and_hash_and_fetch(
         self,
         origin: str,
@@ -560,11 +587,15 @@ class FederationClient(FederationBase):
         Returns:
             A list of PDUs that have valid signatures and hashes.
         """
+        set_tag(
+            SynapseTags.RESULT_PREFIX + "pdus.length",
+            str(len(pdus)),
+        )
 
         # We limit how many PDUs we check at once, as if we try to do hundreds
         # of thousands of PDUs at once we see large memory spikes.
 
-        valid_pdus = []
+        valid_pdus: List[EventBase] = []
 
         async def _execute(pdu: EventBase) -> None:
             valid_pdu = await self._check_sigs_and_hash_and_fetch_one(
@@ -580,6 +611,8 @@ class FederationClient(FederationBase):
 
         return valid_pdus
 
+    @trace
+    @tag_args
     async def _check_sigs_and_hash_and_fetch_one(
         self,
         pdu: EventBase,
@@ -612,16 +645,27 @@ class FederationClient(FederationBase):
         except InvalidEventSignatureError as e:
             logger.warning(
                 "Signature on retrieved event %s was invalid (%s). "
-                "Checking local store/orgin server",
+                "Checking local store/origin server",
                 pdu.event_id,
                 e,
             )
+            log_kv(
+                {
+                    "message": "Signature on retrieved event was invalid. "
+                    "Checking local store/origin server",
+                    "event_id": pdu.event_id,
+                    "InvalidEventSignatureError": e,
+                }
+            )
 
         # Check local db.
         res = await self.store.get_event(
             pdu.event_id, allow_rejected=True, allow_none=True
         )
 
+        # If the PDU fails its signature check and we don't have it in our
+        # database, we then request it from sender's server (if that is not the
+        # same as `origin`).
         pdu_origin = get_domain_from_id(pdu.sender)
         if not res and pdu_origin != origin:
             try:
@@ -725,6 +769,12 @@ class FederationClient(FederationBase):
         if failover_errcodes is None:
             failover_errcodes = ()
 
+        if not destinations:
+            # Give a bit of a clearer message if no servers were specified at all.
+            raise SynapseError(
+                502, f"Failed to {description} via any server: No servers specified."
+            )
+
         for destination in destinations:
             if destination == self.server_name:
                 continue
@@ -774,7 +824,7 @@ class FederationClient(FederationBase):
                     "Failed to %s via %s", description, destination, exc_info=True
                 )
 
-        raise SynapseError(502, "Failed to %s via any server" % (description,))
+        raise SynapseError(502, f"Failed to {description} via any server")
 
     async def make_membership_event(
         self,
diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py
index ae550d3f4d..75fbc6073d 100644
--- a/synapse/federation/federation_server.py
+++ b/synapse/federation/federation_server.py
@@ -61,7 +61,12 @@ from synapse.logging.context import (
     nested_logging_context,
     run_in_background,
 )
-from synapse.logging.opentracing import log_kv, start_active_span_from_edu, trace
+from synapse.logging.opentracing import (
+    log_kv,
+    start_active_span_from_edu,
+    tag_args,
+    trace,
+)
 from synapse.metrics.background_process_metrics import wrap_as_background_process
 from synapse.replication.http.federation import (
     ReplicationFederationSendEduRestServlet,
@@ -469,7 +474,7 @@ class FederationServer(FederationBase):
                     )
                     for pdu in pdus_by_room[room_id]:
                         event_id = pdu.event_id
-                        pdu_results[event_id] = e.error_dict()
+                        pdu_results[event_id] = e.error_dict(self.hs.config)
                     return
 
                 for pdu in pdus_by_room[room_id]:
@@ -547,6 +552,8 @@ class FederationServer(FederationBase):
 
         return 200, resp
 
+    @trace
+    @tag_args
     async def on_state_ids_request(
         self, origin: str, room_id: str, event_id: str
     ) -> Tuple[int, JsonDict]:
@@ -569,6 +576,8 @@ class FederationServer(FederationBase):
 
         return 200, resp
 
+    @trace
+    @tag_args
     async def _on_state_ids_request_compute(
         self, room_id: str, event_id: str
     ) -> JsonDict:
@@ -843,8 +852,25 @@ class FederationServer(FederationBase):
                 Codes.BAD_JSON,
             )
 
+        # Note that get_room_version throws if the room does not exist here.
         room_version = await self.store.get_room_version(room_id)
 
+        if await self.store.is_partial_state_room(room_id):
+            # If our server is still only partially joined, we can't give a complete
+            # response to /send_join, /send_knock or /send_leave.
+            # This is because we will not be able to provide the server list (for partial
+            # joins) or the full state (for full joins).
+            # Return a 404 as we would if we weren't in the room at all.
+            logger.info(
+                f"Rejecting /send_{membership_type} to %s because it's a partial state room",
+                room_id,
+            )
+            raise SynapseError(
+                404,
+                f"Unable to handle /send_{membership_type} right now; this server is not fully joined.",
+                errcode=Codes.NOT_FOUND,
+            )
+
         if membership_type == Membership.KNOCK and not room_version.msc2403_knocking:
             raise SynapseError(
                 403,
diff --git a/synapse/federation/transport/server/_base.py b/synapse/federation/transport/server/_base.py
index 84100a5a52..bb0f8d6b7b 100644
--- a/synapse/federation/transport/server/_base.py
+++ b/synapse/federation/transport/server/_base.py
@@ -309,7 +309,7 @@ class BaseFederationServlet:
                 raise
 
             # update the active opentracing span with the authenticated entity
-            set_tag("authenticated_entity", origin)
+            set_tag("authenticated_entity", str(origin))
 
             # if the origin is authenticated and whitelisted, use its span context
             # as the parent.
diff --git a/synapse/handlers/auth.py b/synapse/handlers/auth.py
index 3d83236b0c..0327fc57a4 100644
--- a/synapse/handlers/auth.py
+++ b/synapse/handlers/auth.py
@@ -280,7 +280,7 @@ class AuthHandler:
         that it isn't stolen by re-authenticating them.
 
         Args:
-            requester: The user, as given by the access token
+            requester: The user making the request, according to the access token.
 
             request: The request sent by the client.
 
@@ -565,7 +565,7 @@ class AuthHandler:
             except LoginError as e:
                 # this step failed. Merge the error dict into the response
                 # so that the client can have another go.
-                errordict = e.error_dict()
+                errordict = e.error_dict(self.hs.config)
 
         creds = await self.store.get_completed_ui_auth_stages(session.session_id)
         for f in flows:
@@ -1435,20 +1435,25 @@ class AuthHandler:
             access_token: access token to be deleted
 
         """
-        user_info = await self.auth.get_user_by_access_token(access_token)
+        token = await self.store.get_user_by_access_token(access_token)
+        if not token:
+            # At this point, the token should already have been fetched once by
+            # the caller, so this should not happen, unless of a race condition
+            # between two delete requests
+            raise SynapseError(HTTPStatus.UNAUTHORIZED, "Unrecognised access token")
         await self.store.delete_access_token(access_token)
 
         # see if any modules want to know about this
         await self.password_auth_provider.on_logged_out(
-            user_id=user_info.user_id,
-            device_id=user_info.device_id,
+            user_id=token.user_id,
+            device_id=token.device_id,
             access_token=access_token,
         )
 
         # delete pushers associated with this access token
-        if user_info.token_id is not None:
+        if token.token_id is not None:
             await self.hs.get_pusherpool().remove_pushers_by_access_token(
-                user_info.user_id, (user_info.token_id,)
+                token.user_id, (token.token_id,)
             )
 
     async def delete_access_tokens_for_user(
diff --git a/synapse/handlers/device.py b/synapse/handlers/device.py
index c05a170c55..f5c586f657 100644
--- a/synapse/handlers/device.py
+++ b/synapse/handlers/device.py
@@ -74,6 +74,7 @@ class DeviceWorkerHandler:
         self._state_storage = hs.get_storage_controllers().state
         self._auth_handler = hs.get_auth_handler()
         self.server_name = hs.hostname
+        self._msc3852_enabled = hs.config.experimental.msc3852_enabled
 
     @trace
     async def get_devices_by_user(self, user_id: str) -> List[JsonDict]:
@@ -118,8 +119,8 @@ class DeviceWorkerHandler:
         ips = await self.store.get_last_client_ip_by_device(user_id, device_id)
         _update_device_from_client_ips(device, ips)
 
-        set_tag("device", device)
-        set_tag("ips", ips)
+        set_tag("device", str(device))
+        set_tag("ips", str(ips))
 
         return device
 
@@ -170,7 +171,7 @@ class DeviceWorkerHandler:
         """
 
         set_tag("user_id", user_id)
-        set_tag("from_token", from_token)
+        set_tag("from_token", str(from_token))
         now_room_key = self.store.get_room_max_token()
 
         room_ids = await self.store.get_rooms_for_user(user_id)
@@ -747,7 +748,13 @@ def _update_device_from_client_ips(
     device: JsonDict, client_ips: Mapping[Tuple[str, str], Mapping[str, Any]]
 ) -> None:
     ip = client_ips.get((device["user_id"], device["device_id"]), {})
-    device.update({"last_seen_ts": ip.get("last_seen"), "last_seen_ip": ip.get("ip")})
+    device.update(
+        {
+            "last_seen_user_agent": ip.get("user_agent"),
+            "last_seen_ts": ip.get("last_seen"),
+            "last_seen_ip": ip.get("ip"),
+        }
+    )
 
 
 class DeviceListUpdater:
@@ -795,7 +802,7 @@ class DeviceListUpdater:
         """
 
         set_tag("origin", origin)
-        set_tag("edu_content", edu_content)
+        set_tag("edu_content", str(edu_content))
         user_id = edu_content.pop("user_id")
         device_id = edu_content.pop("device_id")
         stream_id = str(edu_content.pop("stream_id"))  # They may come as ints
diff --git a/synapse/handlers/directory.py b/synapse/handlers/directory.py
index 09a7a4b238..948f66a94d 100644
--- a/synapse/handlers/directory.py
+++ b/synapse/handlers/directory.py
@@ -30,7 +30,7 @@ from synapse.api.errors import (
 from synapse.appservice import ApplicationService
 from synapse.module_api import NOT_SPAM
 from synapse.storage.databases.main.directory import RoomAliasMapping
-from synapse.types import JsonDict, Requester, RoomAlias, UserID, get_domain_from_id
+from synapse.types import JsonDict, Requester, RoomAlias, get_domain_from_id
 
 if TYPE_CHECKING:
     from synapse.server import HomeServer
@@ -133,7 +133,7 @@ class DirectoryHandler:
         else:
             # Server admins are not subject to the same constraints as normal
             # users when creating an alias (e.g. being in the room).
-            is_admin = await self.auth.is_server_admin(requester.user)
+            is_admin = await self.auth.is_server_admin(requester)
 
             if (self.require_membership and check_membership) and not is_admin:
                 rooms_for_user = await self.store.get_rooms_for_user(user_id)
@@ -197,7 +197,7 @@ class DirectoryHandler:
         user_id = requester.user.to_string()
 
         try:
-            can_delete = await self._user_can_delete_alias(room_alias, user_id)
+            can_delete = await self._user_can_delete_alias(room_alias, requester)
         except StoreError as e:
             if e.code == 404:
                 raise NotFoundError("Unknown room alias")
@@ -400,7 +400,9 @@ class DirectoryHandler:
         # either no interested services, or no service with an exclusive lock
         return True
 
-    async def _user_can_delete_alias(self, alias: RoomAlias, user_id: str) -> bool:
+    async def _user_can_delete_alias(
+        self, alias: RoomAlias, requester: Requester
+    ) -> bool:
         """Determine whether a user can delete an alias.
 
         One of the following must be true:
@@ -413,7 +415,7 @@ class DirectoryHandler:
         """
         creator = await self.store.get_room_alias_creator(alias.to_string())
 
-        if creator == user_id:
+        if creator == requester.user.to_string():
             return True
 
         # Resolve the alias to the corresponding room.
@@ -422,9 +424,7 @@ class DirectoryHandler:
         if not room_id:
             return False
 
-        return await self.auth.check_can_change_room_list(
-            room_id, UserID.from_string(user_id)
-        )
+        return await self.auth.check_can_change_room_list(room_id, requester)
 
     async def edit_published_room_list(
         self, requester: Requester, room_id: str, visibility: str
@@ -463,7 +463,7 @@ class DirectoryHandler:
             raise SynapseError(400, "Unknown room")
 
         can_change_room_list = await self.auth.check_can_change_room_list(
-            room_id, requester.user
+            room_id, requester
         )
         if not can_change_room_list:
             raise AuthError(
@@ -528,10 +528,8 @@ class DirectoryHandler:
         Get a list of the aliases that currently point to this room on this server
         """
         # allow access to server admins and current members of the room
-        is_admin = await self.auth.is_server_admin(requester.user)
+        is_admin = await self.auth.is_server_admin(requester)
         if not is_admin:
-            await self.auth.check_user_in_room_or_world_readable(
-                room_id, requester.user.to_string()
-            )
+            await self.auth.check_user_in_room_or_world_readable(room_id, requester)
 
         return await self.store.get_aliases_for_room(room_id)
diff --git a/synapse/handlers/e2e_keys.py b/synapse/handlers/e2e_keys.py
index 84c28c480e..c938339ddd 100644
--- a/synapse/handlers/e2e_keys.py
+++ b/synapse/handlers/e2e_keys.py
@@ -138,8 +138,8 @@ class E2eKeysHandler:
                 else:
                     remote_queries[user_id] = device_ids
 
-            set_tag("local_key_query", local_query)
-            set_tag("remote_key_query", remote_queries)
+            set_tag("local_key_query", str(local_query))
+            set_tag("remote_key_query", str(remote_queries))
 
             # First get local devices.
             # A map of destination -> failure response.
@@ -343,7 +343,7 @@ class E2eKeysHandler:
             failure = _exception_to_failure(e)
             failures[destination] = failure
             set_tag("error", True)
-            set_tag("reason", failure)
+            set_tag("reason", str(failure))
 
         return
 
@@ -405,7 +405,7 @@ class E2eKeysHandler:
         Returns:
             A map from user_id -> device_id -> device details
         """
-        set_tag("local_query", query)
+        set_tag("local_query", str(query))
         local_query: List[Tuple[str, Optional[str]]] = []
 
         result_dict: Dict[str, Dict[str, dict]] = {}
@@ -477,8 +477,8 @@ class E2eKeysHandler:
                 domain = get_domain_from_id(user_id)
                 remote_queries.setdefault(domain, {})[user_id] = one_time_keys
 
-        set_tag("local_key_query", local_query)
-        set_tag("remote_key_query", remote_queries)
+        set_tag("local_key_query", str(local_query))
+        set_tag("remote_key_query", str(remote_queries))
 
         results = await self.store.claim_e2e_one_time_keys(local_query)
 
@@ -508,7 +508,7 @@ class E2eKeysHandler:
                 failure = _exception_to_failure(e)
                 failures[destination] = failure
                 set_tag("error", True)
-                set_tag("reason", failure)
+                set_tag("reason", str(failure))
 
         await make_deferred_yieldable(
             defer.gatherResults(
@@ -611,7 +611,7 @@ class E2eKeysHandler:
 
         result = await self.store.count_e2e_one_time_keys(user_id, device_id)
 
-        set_tag("one_time_key_counts", result)
+        set_tag("one_time_key_counts", str(result))
         return {"one_time_key_counts": result}
 
     async def _upload_one_time_keys_for_user(
diff --git a/synapse/handlers/e2e_room_keys.py b/synapse/handlers/e2e_room_keys.py
index 446f509bdc..28dc08c22a 100644
--- a/synapse/handlers/e2e_room_keys.py
+++ b/synapse/handlers/e2e_room_keys.py
@@ -14,7 +14,7 @@
 # limitations under the License.
 
 import logging
-from typing import TYPE_CHECKING, Dict, Optional
+from typing import TYPE_CHECKING, Dict, Optional, cast
 
 from typing_extensions import Literal
 
@@ -97,7 +97,7 @@ class E2eRoomKeysHandler:
                 user_id, version, room_id, session_id
             )
 
-            log_kv(results)
+            log_kv(cast(JsonDict, results))
             return results
 
     @trace
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index 11a005f0bf..4bb4d09d4a 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -32,6 +32,7 @@ from typing import (
 )
 
 import attr
+from prometheus_client import Histogram
 from signedjson.key import decode_verify_key_bytes
 from signedjson.sign import verify_signed_json
 from unpaddedbase64 import decode_base64
@@ -59,6 +60,7 @@ from synapse.events.validator import EventValidator
 from synapse.federation.federation_client import InvalidResponseError
 from synapse.http.servlet import assert_params_in_dict
 from synapse.logging.context import nested_logging_context
+from synapse.logging.opentracing import SynapseTags, set_tag, tag_args, trace
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.module_api import NOT_SPAM
 from synapse.replication.http.federation import (
@@ -78,6 +80,29 @@ if TYPE_CHECKING:
 
 logger = logging.getLogger(__name__)
 
+# Added to debug performance and track progress on optimizations
+backfill_processing_before_timer = Histogram(
+    "synapse_federation_backfill_processing_before_time_seconds",
+    "sec",
+    [],
+    buckets=(
+        0.1,
+        0.5,
+        1.0,
+        2.5,
+        5.0,
+        7.5,
+        10.0,
+        15.0,
+        20.0,
+        30.0,
+        40.0,
+        60.0,
+        80.0,
+        "+Inf",
+    ),
+)
+
 
 def get_domains_from_state(state: StateMap[EventBase]) -> List[Tuple[str, int]]:
     """Get joined domains from state
@@ -137,6 +162,7 @@ class FederationHandler:
     def __init__(self, hs: "HomeServer"):
         self.hs = hs
 
+        self.clock = hs.get_clock()
         self.store = hs.get_datastores().main
         self._storage_controllers = hs.get_storage_controllers()
         self._state_storage_controller = self._storage_controllers.state
@@ -180,6 +206,7 @@ class FederationHandler:
                 "resume_sync_partial_state_room", self._resume_sync_partial_state_room
             )
 
+    @trace
     async def maybe_backfill(
         self, room_id: str, current_depth: int, limit: int
     ) -> bool:
@@ -195,12 +222,39 @@ class FederationHandler:
                 return. This is used as part of the heuristic to decide if we
                 should back paginate.
         """
+        # Starting the processing time here so we can include the room backfill
+        # linearizer lock queue in the timing
+        processing_start_time = self.clock.time_msec()
+
         async with self._room_backfill.queue(room_id):
-            return await self._maybe_backfill_inner(room_id, current_depth, limit)
+            return await self._maybe_backfill_inner(
+                room_id,
+                current_depth,
+                limit,
+                processing_start_time=processing_start_time,
+            )
 
     async def _maybe_backfill_inner(
-        self, room_id: str, current_depth: int, limit: int
+        self,
+        room_id: str,
+        current_depth: int,
+        limit: int,
+        *,
+        processing_start_time: int,
     ) -> bool:
+        """
+        Checks whether the `current_depth` is at or approaching any backfill
+        points in the room and if so, will backfill. We only care about
+        checking backfill points that happened before the `current_depth`
+        (meaning less than or equal to the `current_depth`).
+
+        Args:
+            room_id: The room to backfill in.
+            current_depth: The depth to check at for any upcoming backfill points.
+            limit: The max number of events to request from the remote federated server.
+            processing_start_time: The time when `maybe_backfill` started
+                processing. Only used for timing.
+        """
         backwards_extremities = [
             _BackfillPoint(event_id, depth, _BackfillPointType.BACKWARDS_EXTREMITY)
             for event_id, depth in await self.store.get_oldest_event_ids_with_depth_in_room(
@@ -368,6 +422,14 @@ class FederationHandler:
         logger.debug(
             "_maybe_backfill_inner: extremities_to_request %s", extremities_to_request
         )
+        set_tag(
+            SynapseTags.RESULT_PREFIX + "extremities_to_request",
+            str(extremities_to_request),
+        )
+        set_tag(
+            SynapseTags.RESULT_PREFIX + "extremities_to_request.length",
+            str(len(extremities_to_request)),
+        )
 
         # Now we need to decide which hosts to hit first.
 
@@ -423,6 +485,11 @@ class FederationHandler:
 
             return False
 
+        processing_end_time = self.clock.time_msec()
+        backfill_processing_before_timer.observe(
+            (processing_end_time - processing_start_time) / 1000
+        )
+
         success = await try_backfill(likely_domains)
         if success:
             return True
@@ -546,9 +613,9 @@ class FederationHandler:
             )
 
             if ret.partial_state:
-                # TODO(faster_joins): roll this back if we don't manage to start the
-                #   background resync (eg process_remote_join fails)
-                #   https://github.com/matrix-org/synapse/issues/12998
+                # Mark the room as having partial state.
+                # The background process is responsible for unmarking this flag,
+                # even if the join fails.
                 await self.store.store_partial_state_room(room_id, ret.servers_in_room)
 
             try:
@@ -574,17 +641,21 @@ class FederationHandler:
                     room_id,
                 )
                 raise LimitExceededError(msg=e.msg, errcode=e.errcode, retry_after_ms=0)
-
-            if ret.partial_state:
-                # Kick off the process of asynchronously fetching the state for this
-                # room.
-                run_as_background_process(
-                    desc="sync_partial_state_room",
-                    func=self._sync_partial_state_room,
-                    initial_destination=origin,
-                    other_destinations=ret.servers_in_room,
-                    room_id=room_id,
-                )
+            finally:
+                # Always kick off the background process that asynchronously fetches
+                # state for the room.
+                # If the join failed, the background process is responsible for
+                # cleaning up — including unmarking the room as a partial state room.
+                if ret.partial_state:
+                    # Kick off the process of asynchronously fetching the state for this
+                    # room.
+                    run_as_background_process(
+                        desc="sync_partial_state_room",
+                        func=self._sync_partial_state_room,
+                        initial_destination=origin,
+                        other_destinations=ret.servers_in_room,
+                        room_id=room_id,
+                    )
 
             # We wait here until this instance has seen the events come down
             # replication (if we're using replication) as the below uses caches.
@@ -748,6 +819,23 @@ class FederationHandler:
         # (and return a 404 otherwise)
         room_version = await self.store.get_room_version(room_id)
 
+        if await self.store.is_partial_state_room(room_id):
+            # If our server is still only partially joined, we can't give a complete
+            # response to /make_join, so return a 404 as we would if we weren't in the
+            # room at all.
+            # The main reason we can't respond properly is that we need to know about
+            # the auth events for the join event that we would return.
+            # We also should not bother entertaining the /make_join since we cannot
+            # handle the /send_join.
+            logger.info(
+                "Rejecting /make_join to %s because it's a partial state room", room_id
+            )
+            raise SynapseError(
+                404,
+                "Unable to handle /make_join right now; this server is not fully joined.",
+                errcode=Codes.NOT_FOUND,
+            )
+
         # now check that we are *still* in the room
         is_in_room = await self._event_auth_handler.check_host_in_room(
             room_id, self.server_name
@@ -1071,6 +1159,8 @@ class FederationHandler:
 
         return event
 
+    @trace
+    @tag_args
     async def get_state_ids_for_pdu(self, room_id: str, event_id: str) -> List[str]:
         """Returns the state at the event. i.e. not including said event."""
         event = await self.store.get_event(event_id, check_room_id=room_id)
@@ -1552,15 +1642,16 @@ class FederationHandler:
 
         # Make an infinite iterator of destinations to try. Once we find a working
         # destination, we'll stick with it until it flakes.
+        destinations: Collection[str]
         if initial_destination is not None:
             # Move `initial_destination` to the front of the list.
             destinations = list(other_destinations)
             if initial_destination in destinations:
                 destinations.remove(initial_destination)
             destinations = [initial_destination] + destinations
-            destination_iter = itertools.cycle(destinations)
         else:
-            destination_iter = itertools.cycle(other_destinations)
+            destinations = other_destinations
+        destination_iter = itertools.cycle(destinations)
 
         # `destination` is the current remote homeserver we're pulling from.
         destination = next(destination_iter)
diff --git a/synapse/handlers/federation_event.py b/synapse/handlers/federation_event.py
index a5f4ce7c8a..048c4111f6 100644
--- a/synapse/handlers/federation_event.py
+++ b/synapse/handlers/federation_event.py
@@ -29,7 +29,7 @@ from typing import (
     Tuple,
 )
 
-from prometheus_client import Counter
+from prometheus_client import Counter, Histogram
 
 from synapse import event_auth
 from synapse.api.constants import (
@@ -59,6 +59,13 @@ from synapse.events import EventBase
 from synapse.events.snapshot import EventContext
 from synapse.federation.federation_client import InvalidResponseError
 from synapse.logging.context import nested_logging_context
+from synapse.logging.opentracing import (
+    SynapseTags,
+    set_tag,
+    start_active_span,
+    tag_args,
+    trace,
+)
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.replication.http.devices import ReplicationUserDevicesResyncRestServlet
 from synapse.replication.http.federation import (
@@ -91,6 +98,36 @@ soft_failed_event_counter = Counter(
     "Events received over federation that we marked as soft_failed",
 )
 
+# Added to debug performance and track progress on optimizations
+backfill_processing_after_timer = Histogram(
+    "synapse_federation_backfill_processing_after_time_seconds",
+    "sec",
+    [],
+    buckets=(
+        0.1,
+        0.25,
+        0.5,
+        1.0,
+        2.5,
+        5.0,
+        7.5,
+        10.0,
+        15.0,
+        20.0,
+        25.0,
+        30.0,
+        40.0,
+        50.0,
+        60.0,
+        80.0,
+        100.0,
+        120.0,
+        150.0,
+        180.0,
+        "+Inf",
+    ),
+)
+
 
 class FederationEventHandler:
     """Handles events that originated from federation.
@@ -278,7 +315,8 @@ class FederationEventHandler:
                 )
 
         try:
-            await self._process_received_pdu(origin, pdu, state_ids=None)
+            context = await self._state_handler.compute_event_context(pdu)
+            await self._process_received_pdu(origin, pdu, context)
         except PartialStateConflictError:
             # The room was un-partial stated while we were processing the PDU.
             # Try once more, with full state this time.
@@ -286,7 +324,8 @@ class FederationEventHandler:
                 "Room %s was un-partial stated while processing the PDU, trying again.",
                 room_id,
             )
-            await self._process_received_pdu(origin, pdu, state_ids=None)
+            context = await self._state_handler.compute_event_context(pdu)
+            await self._process_received_pdu(origin, pdu, context)
 
     async def on_send_membership_event(
         self, origin: str, event: EventBase
@@ -316,6 +355,7 @@ class FederationEventHandler:
             The event and context of the event after inserting it into the room graph.
 
         Raises:
+            RuntimeError if any prev_events are missing
             SynapseError if the event is not accepted into the room
             PartialStateConflictError if the room was un-partial stated in between
                 computing the state at the event and persisting it. The caller should
@@ -376,7 +416,7 @@ class FederationEventHandler:
         # need to.
         await self._event_creation_handler.cache_joined_hosts_for_event(event, context)
 
-        await self._check_for_soft_fail(event, None, origin=origin)
+        await self._check_for_soft_fail(event, context=context, origin=origin)
         await self._run_push_actions_and_persist_event(event, context)
         return event, context
 
@@ -406,6 +446,7 @@ class FederationEventHandler:
             prev_member_event,
         )
 
+    @trace
     async def process_remote_join(
         self,
         origin: str,
@@ -534,32 +575,36 @@ class FederationEventHandler:
             #
             # This is the same operation as we do when we receive a regular event
             # over federation.
-            state_ids = await self._resolve_state_at_missing_prevs(destination, event)
-
-            # build a new state group for it if need be
-            context = await self._state_handler.compute_event_context(
-                event,
-                state_ids_before_event=state_ids,
+            context = await self._compute_event_context_with_maybe_missing_prevs(
+                destination, event
             )
             if context.partial_state:
                 # this can happen if some or all of the event's prev_events still have
-                # partial state - ie, an event has an earlier stream_ordering than one
-                # or more of its prev_events, so we de-partial-state it before its
-                # prev_events.
+                # partial state. We were careful to only pick events from the db without
+                # partial-state prev events, so that implies that a prev event has
+                # been persisted (with partial state) since we did the query.
                 #
-                # TODO(faster_joins): we probably need to be more intelligent, and
-                #    exclude partial-state prev_events from consideration
-                #    https://github.com/matrix-org/synapse/issues/13001
+                # So, let's just ignore `event` for now; when we re-run the db query
+                # we should instead get its partial-state prev event, which we will
+                # de-partial-state, and then come back to event.
                 logger.warning(
-                    "%s still has partial state: can't de-partial-state it yet",
+                    "%s still has prev_events with partial state: can't de-partial-state it yet",
                     event.event_id,
                 )
                 return
+
+            # since the state at this event has changed, we should now re-evaluate
+            # whether it should have been rejected. We must already have all of the
+            # auth events (from last time we went round this path), so there is no
+            # need to pass the origin.
+            await self._check_event_auth(None, event, context)
+
             await self._store.update_state_for_partial_state_event(event, context)
             self._state_storage_controller.notify_event_un_partial_stated(
                 event.event_id
             )
 
+    @trace
     async def backfill(
         self, dest: str, room_id: str, limit: int, extremities: Collection[str]
     ) -> None:
@@ -589,21 +634,23 @@ class FederationEventHandler:
         if not events:
             return
 
-        # if there are any events in the wrong room, the remote server is buggy and
-        # should not be trusted.
-        for ev in events:
-            if ev.room_id != room_id:
-                raise InvalidResponseError(
-                    f"Remote server {dest} returned event {ev.event_id} which is in "
-                    f"room {ev.room_id}, when we were backfilling in {room_id}"
-                )
+        with backfill_processing_after_timer.time():
+            # if there are any events in the wrong room, the remote server is buggy and
+            # should not be trusted.
+            for ev in events:
+                if ev.room_id != room_id:
+                    raise InvalidResponseError(
+                        f"Remote server {dest} returned event {ev.event_id} which is in "
+                        f"room {ev.room_id}, when we were backfilling in {room_id}"
+                    )
 
-        await self._process_pulled_events(
-            dest,
-            events,
-            backfilled=True,
-        )
+            await self._process_pulled_events(
+                dest,
+                events,
+                backfilled=True,
+            )
 
+    @trace
     async def _get_missing_events_for_pdu(
         self, origin: str, pdu: EventBase, prevs: Set[str], min_depth: int
     ) -> None:
@@ -704,8 +751,9 @@ class FederationEventHandler:
         logger.info("Got %d prev_events", len(missing_events))
         await self._process_pulled_events(origin, missing_events, backfilled=False)
 
+    @trace
     async def _process_pulled_events(
-        self, origin: str, events: Iterable[EventBase], backfilled: bool
+        self, origin: str, events: Collection[EventBase], backfilled: bool
     ) -> None:
         """Process a batch of events we have pulled from a remote server
 
@@ -720,6 +768,15 @@ class FederationEventHandler:
             backfilled: True if this is part of a historical batch of events (inhibits
                 notification to clients, and validation of device keys.)
         """
+        set_tag(
+            SynapseTags.FUNC_ARG_PREFIX + "event_ids",
+            str([event.event_id for event in events]),
+        )
+        set_tag(
+            SynapseTags.FUNC_ARG_PREFIX + "event_ids.length",
+            str(len(events)),
+        )
+        set_tag(SynapseTags.FUNC_ARG_PREFIX + "backfilled", str(backfilled))
         logger.debug(
             "processing pulled backfilled=%s events=%s",
             backfilled,
@@ -742,6 +799,8 @@ class FederationEventHandler:
             with nested_logging_context(ev.event_id):
                 await self._process_pulled_event(origin, ev, backfilled=backfilled)
 
+    @trace
+    @tag_args
     async def _process_pulled_event(
         self, origin: str, event: EventBase, backfilled: bool
     ) -> None:
@@ -793,7 +852,7 @@ class FederationEventHandler:
         if existing:
             if not existing.internal_metadata.is_outlier():
                 logger.info(
-                    "Ignoring received event %s which we have already seen",
+                    "_process_pulled_event: Ignoring received event %s which we have already seen",
                     event_id,
                 )
                 return
@@ -806,29 +865,56 @@ class FederationEventHandler:
             return
 
         try:
-            state_ids = await self._resolve_state_at_missing_prevs(origin, event)
-            # TODO(faster_joins): make sure that _resolve_state_at_missing_prevs does
-            #   not return partial state
-            #   https://github.com/matrix-org/synapse/issues/13002
+            try:
+                context = await self._compute_event_context_with_maybe_missing_prevs(
+                    origin, event
+                )
+                await self._process_received_pdu(
+                    origin,
+                    event,
+                    context,
+                    backfilled=backfilled,
+                )
+            except PartialStateConflictError:
+                # The room was un-partial stated while we were processing the event.
+                # Try once more, with full state this time.
+                context = await self._compute_event_context_with_maybe_missing_prevs(
+                    origin, event
+                )
 
-            await self._process_received_pdu(
-                origin, event, state_ids=state_ids, backfilled=backfilled
-            )
+                # We ought to have full state now, barring some unlikely race where we left and
+                # rejoned the room in the background.
+                if context.partial_state:
+                    raise AssertionError(
+                        f"Event {event.event_id} still has a partial resolved state "
+                        f"after room {event.room_id} was un-partial stated"
+                    )
+
+                await self._process_received_pdu(
+                    origin,
+                    event,
+                    context,
+                    backfilled=backfilled,
+                )
         except FederationError as e:
             if e.code == 403:
                 logger.warning("Pulled event %s failed history check.", event_id)
             else:
                 raise
 
-    async def _resolve_state_at_missing_prevs(
+    @trace
+    async def _compute_event_context_with_maybe_missing_prevs(
         self, dest: str, event: EventBase
-    ) -> Optional[StateMap[str]]:
-        """Calculate the state at an event with missing prev_events.
+    ) -> EventContext:
+        """Build an EventContext structure for a non-outlier event whose prev_events may
+        be missing.
 
-        This is used when we have pulled a batch of events from a remote server, and
-        still don't have all the prev_events.
+        This is used when we have pulled a batch of events from a remote server, and may
+        not have all the prev_events.
 
-        If we already have all the prev_events for `event`, this method does nothing.
+        To build an EventContext, we need to calculate the state before the event. If we
+        already have all the prev_events for `event`, we can simply use the state after
+        the prev_events to calculate the state before `event`.
 
         Otherwise, the missing prevs become new backwards extremities, and we fall back
         to asking the remote server for the state after each missing `prev_event`,
@@ -849,8 +935,7 @@ class FederationEventHandler:
             event: an event to check for missing prevs.
 
         Returns:
-            if we already had all the prev events, `None`. Otherwise, returns
-            the event ids of the state at `event`.
+            The event context.
 
         Raises:
             FederationError if we fail to get the state from the remote server after any
@@ -864,7 +949,7 @@ class FederationEventHandler:
         missing_prevs = prevs - seen
 
         if not missing_prevs:
-            return None
+            return await self._state_handler.compute_event_context(event)
 
         logger.info(
             "Event %s is missing prev_events %s: calculating state for a "
@@ -876,9 +961,15 @@ class FederationEventHandler:
         # resolve them to find the correct state at the current event.
 
         try:
+            # Determine whether we may be about to retrieve partial state
+            # Events may be un-partial stated right after we compute the partial state
+            # flag, but that's okay, as long as the flag errs on the conservative side.
+            partial_state_flags = await self._store.get_partial_state_events(seen)
+            partial_state = any(partial_state_flags.values())
+
             # Get the state of the events we know about
             ours = await self._state_storage_controller.get_state_groups_ids(
-                room_id, seen
+                room_id, seen, await_full_state=False
             )
 
             # state_maps is a list of mappings from (type, state_key) to event_id
@@ -924,8 +1015,12 @@ class FederationEventHandler:
                 "We can't get valid state history.",
                 affected=event_id,
             )
-        return state_map
+        return await self._state_handler.compute_event_context(
+            event, state_ids_before_event=state_map, partial_state=partial_state
+        )
 
+    @trace
+    @tag_args
     async def _get_state_ids_after_missing_prev_event(
         self,
         destination: str,
@@ -965,10 +1060,10 @@ class FederationEventHandler:
         logger.debug("Fetching %i events from cache/store", len(desired_events))
         have_events = await self._store.have_seen_events(room_id, desired_events)
 
-        missing_desired_events = desired_events - have_events
+        missing_desired_event_ids = desired_events - have_events
         logger.debug(
             "We are missing %i events (got %i)",
-            len(missing_desired_events),
+            len(missing_desired_event_ids),
             len(have_events),
         )
 
@@ -980,13 +1075,30 @@ class FederationEventHandler:
         #   already have a bunch of the state events. It would be nice if the
         #   federation api gave us a way of finding out which we actually need.
 
-        missing_auth_events = set(auth_event_ids) - have_events
-        missing_auth_events.difference_update(
-            await self._store.have_seen_events(room_id, missing_auth_events)
+        missing_auth_event_ids = set(auth_event_ids) - have_events
+        missing_auth_event_ids.difference_update(
+            await self._store.have_seen_events(room_id, missing_auth_event_ids)
         )
-        logger.debug("We are also missing %i auth events", len(missing_auth_events))
+        logger.debug("We are also missing %i auth events", len(missing_auth_event_ids))
+
+        missing_event_ids = missing_desired_event_ids | missing_auth_event_ids
 
-        missing_events = missing_desired_events | missing_auth_events
+        set_tag(
+            SynapseTags.RESULT_PREFIX + "missing_auth_event_ids",
+            str(missing_auth_event_ids),
+        )
+        set_tag(
+            SynapseTags.RESULT_PREFIX + "missing_auth_event_ids.length",
+            str(len(missing_auth_event_ids)),
+        )
+        set_tag(
+            SynapseTags.RESULT_PREFIX + "missing_desired_event_ids",
+            str(missing_desired_event_ids),
+        )
+        set_tag(
+            SynapseTags.RESULT_PREFIX + "missing_desired_event_ids.length",
+            str(len(missing_desired_event_ids)),
+        )
 
         # Making an individual request for each of 1000s of events has a lot of
         # overhead. On the other hand, we don't really want to fetch all of the events
@@ -997,13 +1109,13 @@ class FederationEventHandler:
         #
         # TODO: might it be better to have an API which lets us do an aggregate event
         #   request
-        if (len(missing_events) * 10) >= len(auth_event_ids) + len(state_event_ids):
+        if (len(missing_event_ids) * 10) >= len(auth_event_ids) + len(state_event_ids):
             logger.debug("Requesting complete state from remote")
             await self._get_state_and_persist(destination, room_id, event_id)
         else:
-            logger.debug("Fetching %i events from remote", len(missing_events))
+            logger.debug("Fetching %i events from remote", len(missing_event_ids))
             await self._get_events_and_persist(
-                destination=destination, room_id=room_id, event_ids=missing_events
+                destination=destination, room_id=room_id, event_ids=missing_event_ids
             )
 
         # We now need to fill out the state map, which involves fetching the
@@ -1060,6 +1172,14 @@ class FederationEventHandler:
                 event_id,
                 failed_to_fetch,
             )
+            set_tag(
+                SynapseTags.RESULT_PREFIX + "failed_to_fetch",
+                str(failed_to_fetch),
+            )
+            set_tag(
+                SynapseTags.RESULT_PREFIX + "failed_to_fetch.length",
+                str(len(failed_to_fetch)),
+            )
 
         if remote_event.is_state() and remote_event.rejected_reason is None:
             state_map[
@@ -1068,6 +1188,8 @@ class FederationEventHandler:
 
         return state_map
 
+    @trace
+    @tag_args
     async def _get_state_and_persist(
         self, destination: str, room_id: str, event_id: str
     ) -> None:
@@ -1089,11 +1211,12 @@ class FederationEventHandler:
                 destination=destination, room_id=room_id, event_ids=(event_id,)
             )
 
+    @trace
     async def _process_received_pdu(
         self,
         origin: str,
         event: EventBase,
-        state_ids: Optional[StateMap[str]],
+        context: EventContext,
         backfilled: bool = False,
     ) -> None:
         """Called when we have a new non-outlier event.
@@ -1115,24 +1238,18 @@ class FederationEventHandler:
 
             event: event to be persisted
 
-            state_ids: Normally None, but if we are handling a gap in the graph
-                (ie, we are missing one or more prev_events), the resolved state at the
-                event. Must not be partial state.
+            context: The `EventContext` to persist the event with.
 
             backfilled: True if this is part of a historical batch of events (inhibits
                 notification to clients, and validation of device keys.)
 
         PartialStateConflictError: if the room was un-partial stated in between
-            computing the state at the event and persisting it. The caller should retry
-            exactly once in this case. Will never be raised if `state_ids` is provided.
+            computing the state at the event and persisting it. The caller should
+            recompute `context` and retry exactly once when this happens.
         """
         logger.debug("Processing event: %s", event)
         assert not event.internal_metadata.outlier
 
-        context = await self._state_handler.compute_event_context(
-            event,
-            state_ids_before_event=state_ids,
-        )
         try:
             await self._check_event_auth(origin, event, context)
         except AuthError as e:
@@ -1144,7 +1261,7 @@ class FederationEventHandler:
             # For new (non-backfilled and non-outlier) events we check if the event
             # passes auth based on the current state. If it doesn't then we
             # "soft-fail" the event.
-            await self._check_for_soft_fail(event, state_ids, origin=origin)
+            await self._check_for_soft_fail(event, context=context, origin=origin)
 
         await self._run_push_actions_and_persist_event(event, context, backfilled)
 
@@ -1245,6 +1362,7 @@ class FederationEventHandler:
         except Exception:
             logger.exception("Failed to resync device for %s", sender)
 
+    @trace
     async def _handle_marker_event(self, origin: str, marker_event: EventBase) -> None:
         """Handles backfilling the insertion event when we receive a marker
         event that points to one.
@@ -1276,7 +1394,7 @@ class FederationEventHandler:
         logger.debug("_handle_marker_event: received %s", marker_event)
 
         insertion_event_id = marker_event.content.get(
-            EventContentFields.MSC2716_MARKER_INSERTION
+            EventContentFields.MSC2716_INSERTION_EVENT_REFERENCE
         )
 
         if insertion_event_id is None:
@@ -1329,6 +1447,55 @@ class FederationEventHandler:
             marker_event,
         )
 
+    async def backfill_event_id(
+        self, destination: str, room_id: str, event_id: str
+    ) -> EventBase:
+        """Backfill a single event and persist it as a non-outlier which means
+        we also pull in all of the state and auth events necessary for it.
+
+        Args:
+            destination: The homeserver to pull the given event_id from.
+            room_id: The room where the event is from.
+            event_id: The event ID to backfill.
+
+        Raises:
+            FederationError if we are unable to find the event from the destination
+        """
+        logger.info(
+            "backfill_event_id: event_id=%s from destination=%s", event_id, destination
+        )
+
+        room_version = await self._store.get_room_version(room_id)
+
+        event_from_response = await self._federation_client.get_pdu(
+            [destination],
+            event_id,
+            room_version,
+        )
+
+        if not event_from_response:
+            raise FederationError(
+                "ERROR",
+                404,
+                "Unable to find event_id=%s from destination=%s to backfill."
+                % (event_id, destination),
+                affected=event_id,
+            )
+
+        # Persist the event we just fetched, including pulling all of the state
+        # and auth events to de-outlier it. This also sets up the necessary
+        # `state_groups` for the event.
+        await self._process_pulled_events(
+            destination,
+            [event_from_response],
+            # Prevent notifications going to clients
+            backfilled=True,
+        )
+
+        return event_from_response
+
+    @trace
+    @tag_args
     async def _get_events_and_persist(
         self, destination: str, room_id: str, event_ids: Collection[str]
     ) -> None:
@@ -1374,6 +1541,7 @@ class FederationEventHandler:
         logger.info("Fetched %i events of %i requested", len(events), len(event_ids))
         await self._auth_and_persist_outliers(room_id, events)
 
+    @trace
     async def _auth_and_persist_outliers(
         self, room_id: str, events: Iterable[EventBase]
     ) -> None:
@@ -1392,6 +1560,16 @@ class FederationEventHandler:
         """
         event_map = {event.event_id: event for event in events}
 
+        event_ids = event_map.keys()
+        set_tag(
+            SynapseTags.FUNC_ARG_PREFIX + "event_ids",
+            str(event_ids),
+        )
+        set_tag(
+            SynapseTags.FUNC_ARG_PREFIX + "event_ids.length",
+            str(len(event_ids)),
+        )
+
         # filter out any events we have already seen. This might happen because
         # the events were eagerly pushed to us (eg, during a room join), or because
         # another thread has raced against us since we decided to request the event.
@@ -1508,14 +1686,17 @@ class FederationEventHandler:
             backfilled=True,
         )
 
+    @trace
     async def _check_event_auth(
-        self, origin: str, event: EventBase, context: EventContext
+        self, origin: Optional[str], event: EventBase, context: EventContext
     ) -> None:
         """
         Checks whether an event should be rejected (for failing auth checks).
 
         Args:
-            origin: The host the event originates from.
+            origin: The host the event originates from. This is used to fetch
+               any missing auth events. It can be set to None, but only if we are
+               sure that we already have all the auth events.
             event: The event itself.
             context:
                 The event context.
@@ -1544,6 +1725,14 @@ class FederationEventHandler:
         claimed_auth_events = await self._load_or_fetch_auth_events_for_event(
             origin, event
         )
+        set_tag(
+            SynapseTags.RESULT_PREFIX + "claimed_auth_events",
+            str([ev.event_id for ev in claimed_auth_events]),
+        )
+        set_tag(
+            SynapseTags.RESULT_PREFIX + "claimed_auth_events.length",
+            str(len(claimed_auth_events)),
+        )
 
         # ... and check that the event passes auth at those auth events.
         # https://spec.matrix.org/v1.3/server-server-api/#checks-performed-on-receipt-of-a-pdu:
@@ -1641,6 +1830,7 @@ class FederationEventHandler:
             )
             context.rejected = RejectedReason.AUTH_ERROR
 
+    @trace
     async def _maybe_kick_guest_users(self, event: EventBase) -> None:
         if event.type != EventTypes.GuestAccess:
             return
@@ -1658,17 +1848,27 @@ class FederationEventHandler:
     async def _check_for_soft_fail(
         self,
         event: EventBase,
-        state_ids: Optional[StateMap[str]],
+        context: EventContext,
         origin: str,
     ) -> None:
         """Checks if we should soft fail the event; if so, marks the event as
         such.
 
+        Does nothing for events in rooms with partial state, since we may not have an
+        accurate membership event for the sender in the current state.
+
         Args:
             event
-            state_ids: The state at the event if we don't have all the event's prev events
+            context: The `EventContext` which we are about to persist the event with.
             origin: The host the event originates from.
         """
+        if await self._store.is_partial_state_room(event.room_id):
+            # We might not know the sender's membership in the current state, so don't
+            # soft fail anything. Even if we do have a membership for the sender in the
+            # current state, it may have been derived from state resolution between
+            # partial and full state and may not be accurate.
+            return
+
         extrem_ids_list = await self._store.get_latest_event_ids_in_room(event.room_id)
         extrem_ids = set(extrem_ids_list)
         prev_event_ids = set(event.prev_event_ids())
@@ -1685,11 +1885,15 @@ class FederationEventHandler:
         auth_types = auth_types_for_event(room_version_obj, event)
 
         # Calculate the "current state".
-        if state_ids is not None:
-            # If we're explicitly given the state then we won't have all the
-            # prev events, and so we have a gap in the graph. In this case
-            # we want to be a little careful as we might have been down for
-            # a while and have an incorrect view of the current state,
+        seen_event_ids = await self._store.have_events_in_timeline(prev_event_ids)
+        has_missing_prevs = bool(prev_event_ids - seen_event_ids)
+        if has_missing_prevs:
+            # We don't have all the prev_events of this event, which means we have a
+            # gap in the graph, and the new event is going to become a new backwards
+            # extremity.
+            #
+            # In this case we want to be a little careful as we might have been
+            # down for a while and have an incorrect view of the current state,
             # however we still want to do checks as gaps are easy to
             # maliciously manufacture.
             #
@@ -1702,6 +1906,7 @@ class FederationEventHandler:
                 event.room_id, extrem_ids
             )
             state_sets: List[StateMap[str]] = list(state_sets_d.values())
+            state_ids = await context.get_prev_state_ids()
             state_sets.append(state_ids)
             current_state_ids = (
                 await self._state_resolution_handler.resolve_events_with_store(
@@ -1751,7 +1956,7 @@ class FederationEventHandler:
             event.internal_metadata.soft_failed = True
 
     async def _load_or_fetch_auth_events_for_event(
-        self, destination: str, event: EventBase
+        self, destination: Optional[str], event: EventBase
     ) -> Collection[EventBase]:
         """Fetch this event's auth_events, from database or remote
 
@@ -1767,12 +1972,19 @@ class FederationEventHandler:
         Args:
             destination: where to send the /event_auth request. Typically the server
                that sent us `event` in the first place.
+
+               If this is None, no attempt is made to load any missing auth events:
+               rather, an AssertionError is raised if there are any missing events.
+
             event: the event whose auth_events we want
 
         Returns:
             all of the events listed in `event.auth_events_ids`, after deduplication
 
         Raises:
+            AssertionError if some auth events were missing and no `destination` was
+            supplied.
+
             AuthError if we were unable to fetch the auth_events for any reason.
         """
         event_auth_event_ids = set(event.auth_event_ids())
@@ -1784,6 +1996,13 @@ class FederationEventHandler:
         )
         if not missing_auth_event_ids:
             return event_auth_events.values()
+        if destination is None:
+            # this shouldn't happen: destination must be set unless we know we have already
+            # persisted the auth events.
+            raise AssertionError(
+                "_load_or_fetch_auth_events_for_event() called with no destination for "
+                "an event with missing auth_events"
+            )
 
         logger.info(
             "Event %s refers to unknown auth events %s: fetching auth chain",
@@ -1819,6 +2038,8 @@ class FederationEventHandler:
         # instead we raise an AuthError, which will make the caller ignore it.
         raise AuthError(code=HTTPStatus.FORBIDDEN, msg="Auth events could not be found")
 
+    @trace
+    @tag_args
     async def _get_remote_auth_chain_for_event(
         self, destination: str, room_id: str, event_id: str
     ) -> None:
@@ -1847,6 +2068,7 @@ class FederationEventHandler:
 
         await self._auth_and_persist_outliers(room_id, remote_auth_events)
 
+    @trace
     async def _run_push_actions_and_persist_event(
         self, event: EventBase, context: EventContext, backfilled: bool = False
     ) -> None:
@@ -1955,8 +2177,17 @@ class FederationEventHandler:
                     self._message_handler.maybe_schedule_expiry(event)
 
             if not backfilled:  # Never notify for backfilled events
-                for event in events:
-                    await self._notify_persisted_event(event, max_stream_token)
+                with start_active_span("notify_persisted_events"):
+                    set_tag(
+                        SynapseTags.RESULT_PREFIX + "event_ids",
+                        str([ev.event_id for ev in events]),
+                    )
+                    set_tag(
+                        SynapseTags.RESULT_PREFIX + "event_ids.length",
+                        str(len(events)),
+                    )
+                    for event in events:
+                        await self._notify_persisted_event(event, max_stream_token)
 
             return max_stream_token.stream
 
diff --git a/synapse/handlers/initial_sync.py b/synapse/handlers/initial_sync.py
index 85b472f250..860c82c110 100644
--- a/synapse/handlers/initial_sync.py
+++ b/synapse/handlers/initial_sync.py
@@ -143,8 +143,8 @@ class InitialSyncHandler:
             joined_rooms,
             to_key=int(now_token.receipt_key),
         )
-        if self.hs.config.experimental.msc2285_enabled:
-            receipt = ReceiptEventSource.filter_out_private_receipts(receipt, user_id)
+
+        receipt = ReceiptEventSource.filter_out_private_receipts(receipt, user_id)
 
         tags_by_room = await self.store.get_tags_for_user(user_id)
 
@@ -309,18 +309,18 @@ class InitialSyncHandler:
         if blocked:
             raise SynapseError(403, "This room has been blocked on this server")
 
-        user_id = requester.user.to_string()
-
         (
             membership,
             member_event_id,
         ) = await self.auth.check_user_in_room_or_world_readable(
             room_id,
-            user_id,
+            requester,
             allow_departed_users=True,
         )
         is_peeking = member_event_id is None
 
+        user_id = requester.user.to_string()
+
         if membership == Membership.JOIN:
             result = await self._room_initial_sync_joined(
                 user_id, room_id, pagin_config, membership, is_peeking
@@ -456,11 +456,8 @@ class InitialSyncHandler:
             )
             if not receipts:
                 return []
-            if self.hs.config.experimental.msc2285_enabled:
-                receipts = ReceiptEventSource.filter_out_private_receipts(
-                    receipts, user_id
-                )
-            return receipts
+
+            return ReceiptEventSource.filter_out_private_receipts(receipts, user_id)
 
         presence, receipts, (messages, token) = await make_deferred_yieldable(
             gather_results(
diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py
index bd7baef051..acd3de06f6 100644
--- a/synapse/handlers/message.py
+++ b/synapse/handlers/message.py
@@ -41,6 +41,7 @@ from synapse.api.errors import (
     NotFoundError,
     ShadowBanError,
     SynapseError,
+    UnstableSpecAuthError,
     UnsupportedRoomVersionError,
 )
 from synapse.api.room_versions import KNOWN_ROOM_VERSIONS
@@ -51,6 +52,7 @@ from synapse.events.builder import EventBuilder
 from synapse.events.snapshot import EventContext
 from synapse.events.validator import EventValidator
 from synapse.handlers.directory import DirectoryHandler
+from synapse.logging import opentracing
 from synapse.logging.context import make_deferred_yieldable, run_in_background
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.replication.http.send_event import ReplicationSendEventRestServlet
@@ -102,7 +104,7 @@ class MessageHandler:
 
     async def get_room_data(
         self,
-        user_id: str,
+        requester: Requester,
         room_id: str,
         event_type: str,
         state_key: str,
@@ -110,7 +112,7 @@ class MessageHandler:
         """Get data from a room.
 
         Args:
-            user_id
+            requester: The user who did the request.
             room_id
             event_type
             state_key
@@ -123,7 +125,7 @@ class MessageHandler:
             membership,
             membership_event_id,
         ) = await self.auth.check_user_in_room_or_world_readable(
-            room_id, user_id, allow_departed_users=True
+            room_id, requester, allow_departed_users=True
         )
 
         if membership == Membership.JOIN:
@@ -149,17 +151,20 @@ class MessageHandler:
                 "Attempted to retrieve data from a room for a user that has never been in it. "
                 "This should not have happened."
             )
-            raise SynapseError(403, "User not in room", errcode=Codes.FORBIDDEN)
+            raise UnstableSpecAuthError(
+                403,
+                "User not in room",
+                errcode=Codes.NOT_JOINED,
+            )
 
         return data
 
     async def get_state_events(
         self,
-        user_id: str,
+        requester: Requester,
         room_id: str,
         state_filter: Optional[StateFilter] = None,
         at_token: Optional[StreamToken] = None,
-        is_guest: bool = False,
     ) -> List[dict]:
         """Retrieve all state events for a given room. If the user is
         joined to the room then return the current state. If the user has
@@ -168,14 +173,13 @@ class MessageHandler:
         visible.
 
         Args:
-            user_id: The user requesting state events.
+            requester: The user requesting state events.
             room_id: The room ID to get all state events from.
             state_filter: The state filter used to fetch state from the database.
             at_token: the stream token of the at which we are requesting
                 the stats. If the user is not allowed to view the state as of that
                 stream token, we raise a 403 SynapseError. If None, returns the current
                 state based on the current_state_events table.
-            is_guest: whether this user is a guest
         Returns:
             A list of dicts representing state events. [{}, {}, {}]
         Raises:
@@ -185,6 +189,7 @@ class MessageHandler:
             members of this room.
         """
         state_filter = state_filter or StateFilter.all()
+        user_id = requester.user.to_string()
 
         if at_token:
             last_event_id = (
@@ -217,7 +222,7 @@ class MessageHandler:
                 membership,
                 membership_event_id,
             ) = await self.auth.check_user_in_room_or_world_readable(
-                room_id, user_id, allow_departed_users=True
+                room_id, requester, allow_departed_users=True
             )
 
             if membership == Membership.JOIN:
@@ -311,30 +316,42 @@ class MessageHandler:
         Returns:
             A dict of user_id to profile info
         """
-        user_id = requester.user.to_string()
         if not requester.app_service:
             # We check AS auth after fetching the room membership, as it
             # requires us to pull out all joined members anyway.
             membership, _ = await self.auth.check_user_in_room_or_world_readable(
-                room_id, user_id, allow_departed_users=True
+                room_id, requester, allow_departed_users=True
             )
             if membership != Membership.JOIN:
-                raise NotImplementedError(
-                    "Getting joined members after leaving is not implemented"
+                raise SynapseError(
+                    code=403,
+                    errcode=Codes.FORBIDDEN,
+                    msg="Getting joined members while not being a current member of the room is forbidden.",
                 )
 
-        users_with_profile = await self.store.get_users_in_room_with_profiles(room_id)
+        users_with_profile = (
+            await self._state_storage_controller.get_users_in_room_with_profiles(
+                room_id
+            )
+        )
 
         # If this is an AS, double check that they are allowed to see the members.
         # This can either be because the AS user is in the room or because there
         # is a user in the room that the AS is "interested in"
-        if requester.app_service and user_id not in users_with_profile:
+        if (
+            requester.app_service
+            and requester.user.to_string() not in users_with_profile
+        ):
             for uid in users_with_profile:
                 if requester.app_service.is_interested_in_user(uid):
                     break
             else:
                 # Loop fell through, AS has no interested users in room
-                raise AuthError(403, "Appservice not in room")
+                raise UnstableSpecAuthError(
+                    403,
+                    "Appservice not in room",
+                    errcode=Codes.NOT_JOINED,
+                )
 
         return {
             user_id: {
@@ -1135,6 +1152,10 @@ class EventCreationHandler:
             context = await self.state.compute_event_context(
                 event,
                 state_ids_before_event=state_map_for_event,
+                # TODO(faster_joins): check how MSC2716 works and whether we can have
+                #   partial state here
+                #   https://github.com/matrix-org/synapse/issues/13003
+                partial_state=False,
             )
         else:
             context = await self.state.compute_event_context(event)
@@ -1359,9 +1380,10 @@ class EventCreationHandler:
         # and `state_groups` because they have `prev_events` that aren't persisted yet
         # (historical messages persisted in reverse-chronological order).
         if not event.internal_metadata.is_historical():
-            await self._bulk_push_rule_evaluator.action_for_event_by_user(
-                event, context
-            )
+            with opentracing.start_active_span("calculate_push_actions"):
+                await self._bulk_push_rule_evaluator.action_for_event_by_user(
+                    event, context
+                )
 
         try:
             # If we're a worker we need to hit out to the master.
@@ -1448,9 +1470,10 @@ class EventCreationHandler:
             state = await state_entry.get_state(
                 self._storage_controllers.state, StateFilter.all()
             )
-            joined_hosts = await self.store.get_joined_hosts(
-                event.room_id, state, state_entry
-            )
+            with opentracing.start_active_span("get_joined_hosts"):
+                joined_hosts = await self.store.get_joined_hosts(
+                    event.room_id, state, state_entry
+                )
 
             # Note that the expiry times must be larger than the expiry time in
             # _external_cache_joined_hosts_updates.
diff --git a/synapse/handlers/pagination.py b/synapse/handlers/pagination.py
index 6262a35822..74e944bce7 100644
--- a/synapse/handlers/pagination.py
+++ b/synapse/handlers/pagination.py
@@ -24,6 +24,7 @@ from synapse.api.errors import SynapseError
 from synapse.api.filtering import Filter
 from synapse.events.utils import SerializeEventConfig
 from synapse.handlers.room import ShutdownRoomResponse
+from synapse.logging.opentracing import trace
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.storage.state import StateFilter
 from synapse.streams.config import PaginationConfig
@@ -416,6 +417,7 @@ class PaginationHandler:
 
             await self._storage_controllers.purge_events.purge_room(room_id)
 
+    @trace
     async def get_messages(
         self,
         requester: Requester,
@@ -462,7 +464,7 @@ class PaginationHandler:
                 membership,
                 member_event_id,
             ) = await self.auth.check_user_in_room_or_world_readable(
-                room_id, user_id, allow_departed_users=True
+                room_id, requester, allow_departed_users=True
             )
 
             if pagin_config.direction == "b":
diff --git a/synapse/handlers/presence.py b/synapse/handlers/presence.py
index 895ea63ed3..741504ba9f 100644
--- a/synapse/handlers/presence.py
+++ b/synapse/handlers/presence.py
@@ -34,7 +34,6 @@ from typing import (
     Callable,
     Collection,
     Dict,
-    FrozenSet,
     Generator,
     Iterable,
     List,
@@ -42,7 +41,6 @@ from typing import (
     Set,
     Tuple,
     Type,
-    Union,
 )
 
 from prometheus_client import Counter
@@ -68,7 +66,6 @@ from synapse.storage.databases.main import DataStore
 from synapse.streams import EventSource
 from synapse.types import JsonDict, StreamKeyType, UserID, get_domain_from_id
 from synapse.util.async_helpers import Linearizer
-from synapse.util.caches.descriptors import _CacheContext, cached
 from synapse.util.metrics import Measure
 from synapse.util.wheel_timer import WheelTimer
 
@@ -1656,15 +1653,18 @@ class PresenceEventSource(EventSource[int, UserPresenceState]):
                 # doesn't return. C.f. #5503.
                 return [], max_token
 
-            # Figure out which other users this user should receive updates for
-            users_interested_in = await self._get_interested_in(user, explicit_room_id)
+            # Figure out which other users this user should explicitly receive
+            # updates for
+            additional_users_interested_in = (
+                await self.get_presence_router().get_interested_users(user.to_string())
+            )
 
             # We have a set of users that we're interested in the presence of. We want to
             # cross-reference that with the users that have actually changed their presence.
 
             # Check whether this user should see all user updates
 
-            if users_interested_in == PresenceRouter.ALL_USERS:
+            if additional_users_interested_in == PresenceRouter.ALL_USERS:
                 # Provide presence state for all users
                 presence_updates = await self._filter_all_presence_updates_for_user(
                     user_id, include_offline, from_key
@@ -1673,34 +1673,47 @@ class PresenceEventSource(EventSource[int, UserPresenceState]):
                 return presence_updates, max_token
 
             # Make mypy happy. users_interested_in should now be a set
-            assert not isinstance(users_interested_in, str)
+            assert not isinstance(additional_users_interested_in, str)
+
+            # We always care about our own presence.
+            additional_users_interested_in.add(user_id)
+
+            if explicit_room_id:
+                user_ids = await self.store.get_users_in_room(explicit_room_id)
+                additional_users_interested_in.update(user_ids)
 
             # The set of users that we're interested in and that have had a presence update.
             # We'll actually pull the presence updates for these users at the end.
-            interested_and_updated_users: Union[Set[str], FrozenSet[str]] = set()
+            interested_and_updated_users: Collection[str]
 
             if from_key is not None:
                 # First get all users that have had a presence update
                 updated_users = stream_change_cache.get_all_entities_changed(from_key)
 
                 # Cross-reference users we're interested in with those that have had updates.
-                # Use a slightly-optimised method for processing smaller sets of updates.
-                if updated_users is not None and len(updated_users) < 500:
-                    # For small deltas, it's quicker to get all changes and then
-                    # cross-reference with the users we're interested in
+                if updated_users is not None:
+                    # If we have the full list of changes for presence we can
+                    # simply check which ones share a room with the user.
                     get_updates_counter.labels("stream").inc()
-                    for other_user_id in updated_users:
-                        if other_user_id in users_interested_in:
-                            # mypy thinks this variable could be a FrozenSet as it's possibly set
-                            # to one in the `get_entities_changed` call below, and `add()` is not
-                            # method on a FrozenSet. That doesn't affect us here though, as
-                            # `interested_and_updated_users` is clearly a set() above.
-                            interested_and_updated_users.add(other_user_id)  # type: ignore
+
+                    sharing_users = await self.store.do_users_share_a_room(
+                        user_id, updated_users
+                    )
+
+                    interested_and_updated_users = (
+                        sharing_users.union(additional_users_interested_in)
+                    ).intersection(updated_users)
+
                 else:
                     # Too many possible updates. Find all users we can see and check
                     # if any of them have changed.
                     get_updates_counter.labels("full").inc()
 
+                    users_interested_in = (
+                        await self.store.get_users_who_share_room_with_user(user_id)
+                    )
+                    users_interested_in.update(additional_users_interested_in)
+
                     interested_and_updated_users = (
                         stream_change_cache.get_entities_changed(
                             users_interested_in, from_key
@@ -1709,7 +1722,10 @@ class PresenceEventSource(EventSource[int, UserPresenceState]):
             else:
                 # No from_key has been specified. Return the presence for all users
                 # this user is interested in
-                interested_and_updated_users = users_interested_in
+                interested_and_updated_users = (
+                    await self.store.get_users_who_share_room_with_user(user_id)
+                )
+                interested_and_updated_users.update(additional_users_interested_in)
 
             # Retrieve the current presence state for each user
             users_to_state = await self.get_presence_handler().current_state_for_users(
@@ -1804,62 +1820,6 @@ class PresenceEventSource(EventSource[int, UserPresenceState]):
     def get_current_key(self) -> int:
         return self.store.get_current_presence_token()
 
-    @cached(num_args=2, cache_context=True)
-    async def _get_interested_in(
-        self,
-        user: UserID,
-        explicit_room_id: Optional[str] = None,
-        cache_context: Optional[_CacheContext] = None,
-    ) -> Union[Set[str], str]:
-        """Returns the set of users that the given user should see presence
-        updates for.
-
-        Args:
-            user: The user to retrieve presence updates for.
-            explicit_room_id: The users that are in the room will be returned.
-
-        Returns:
-            A set of user IDs to return presence updates for, or "ALL" to return all
-            known updates.
-        """
-        user_id = user.to_string()
-        users_interested_in = set()
-        users_interested_in.add(user_id)  # So that we receive our own presence
-
-        # cache_context isn't likely to ever be None due to the @cached decorator,
-        # but we can't have a non-optional argument after the optional argument
-        # explicit_room_id either. Assert cache_context is not None so we can use it
-        # without mypy complaining.
-        assert cache_context
-
-        # Check with the presence router whether we should poll additional users for
-        # their presence information
-        additional_users = await self.get_presence_router().get_interested_users(
-            user.to_string()
-        )
-        if additional_users == PresenceRouter.ALL_USERS:
-            # If the module requested that this user see the presence updates of *all*
-            # users, then simply return that instead of calculating what rooms this
-            # user shares
-            return PresenceRouter.ALL_USERS
-
-        # Add the additional users from the router
-        users_interested_in.update(additional_users)
-
-        # Find the users who share a room with this user
-        users_who_share_room = await self.store.get_users_who_share_room_with_user(
-            user_id, on_invalidate=cache_context.invalidate
-        )
-        users_interested_in.update(users_who_share_room)
-
-        if explicit_room_id:
-            user_ids = await self.store.get_users_in_room(
-                explicit_room_id, on_invalidate=cache_context.invalidate
-            )
-            users_interested_in.update(user_ids)
-
-        return users_interested_in
-
 
 def handle_timeouts(
     user_states: List[UserPresenceState],
diff --git a/synapse/handlers/receipts.py b/synapse/handlers/receipts.py
index 43d2882b0a..d4a866b346 100644
--- a/synapse/handlers/receipts.py
+++ b/synapse/handlers/receipts.py
@@ -163,7 +163,10 @@ class ReceiptsHandler:
         if not is_new:
             return
 
-        if self.federation_sender and receipt_type != ReceiptTypes.READ_PRIVATE:
+        if self.federation_sender and receipt_type not in (
+            ReceiptTypes.READ_PRIVATE,
+            ReceiptTypes.UNSTABLE_READ_PRIVATE,
+        ):
             await self.federation_sender.send_read_receipt(receipt)
 
 
@@ -203,24 +206,38 @@ class ReceiptEventSource(EventSource[int, JsonDict]):
             for event_id, orig_event_content in room.get("content", {}).items():
                 event_content = orig_event_content
                 # If there are private read receipts, additional logic is necessary.
-                if ReceiptTypes.READ_PRIVATE in event_content:
+                if (
+                    ReceiptTypes.READ_PRIVATE in event_content
+                    or ReceiptTypes.UNSTABLE_READ_PRIVATE in event_content
+                ):
                     # Make a copy without private read receipts to avoid leaking
                     # other user's private read receipts..
                     event_content = {
                         receipt_type: receipt_value
                         for receipt_type, receipt_value in event_content.items()
-                        if receipt_type != ReceiptTypes.READ_PRIVATE
+                        if receipt_type
+                        not in (
+                            ReceiptTypes.READ_PRIVATE,
+                            ReceiptTypes.UNSTABLE_READ_PRIVATE,
+                        )
                     }
 
                     # Copy the current user's private read receipt from the
                     # original content, if it exists.
-                    user_private_read_receipt = orig_event_content[
-                        ReceiptTypes.READ_PRIVATE
-                    ].get(user_id, None)
+                    user_private_read_receipt = orig_event_content.get(
+                        ReceiptTypes.READ_PRIVATE, {}
+                    ).get(user_id, None)
                     if user_private_read_receipt:
                         event_content[ReceiptTypes.READ_PRIVATE] = {
                             user_id: user_private_read_receipt
                         }
+                    user_unstable_private_read_receipt = orig_event_content.get(
+                        ReceiptTypes.UNSTABLE_READ_PRIVATE, {}
+                    ).get(user_id, None)
+                    if user_unstable_private_read_receipt:
+                        event_content[ReceiptTypes.UNSTABLE_READ_PRIVATE] = {
+                            user_id: user_unstable_private_read_receipt
+                        }
 
                 # Include the event if there is at least one non-private read
                 # receipt or the current user has a private read receipt.
@@ -256,10 +273,9 @@ class ReceiptEventSource(EventSource[int, JsonDict]):
             room_ids, from_key=from_key, to_key=to_key
         )
 
-        if self.config.experimental.msc2285_enabled:
-            events = ReceiptEventSource.filter_out_private_receipts(
-                events, user.to_string()
-            )
+        events = ReceiptEventSource.filter_out_private_receipts(
+            events, user.to_string()
+        )
 
         return events, to_key
 
diff --git a/synapse/handlers/register.py b/synapse/handlers/register.py
index c77d181722..20ec22105a 100644
--- a/synapse/handlers/register.py
+++ b/synapse/handlers/register.py
@@ -29,7 +29,13 @@ from synapse.api.constants import (
     JoinRules,
     LoginType,
 )
-from synapse.api.errors import AuthError, Codes, ConsentNotGivenError, SynapseError
+from synapse.api.errors import (
+    AuthError,
+    Codes,
+    ConsentNotGivenError,
+    InvalidClientTokenError,
+    SynapseError,
+)
 from synapse.appservice import ApplicationService
 from synapse.config.server import is_threepid_reserved
 from synapse.http.servlet import assert_params_in_dict
@@ -180,10 +186,7 @@ class RegistrationHandler:
                 )
             if guest_access_token:
                 user_data = await self.auth.get_user_by_access_token(guest_access_token)
-                if (
-                    not user_data.is_guest
-                    or UserID.from_string(user_data.user_id).localpart != localpart
-                ):
+                if not user_data.is_guest or user_data.user.localpart != localpart:
                     raise AuthError(
                         403,
                         "Cannot register taken user ID without valid guest "
@@ -618,7 +621,7 @@ class RegistrationHandler:
         user_id = user.to_string()
         service = self.store.get_app_service_by_token(as_token)
         if not service:
-            raise AuthError(403, "Invalid application service token.")
+            raise InvalidClientTokenError()
         if not service.is_interested_in_user(user_id):
             raise SynapseError(
                 400,
diff --git a/synapse/handlers/relations.py b/synapse/handlers/relations.py
index 0b63cd2186..28d7093f08 100644
--- a/synapse/handlers/relations.py
+++ b/synapse/handlers/relations.py
@@ -19,6 +19,7 @@ import attr
 from synapse.api.constants import RelationTypes
 from synapse.api.errors import SynapseError
 from synapse.events import EventBase, relation_from_event
+from synapse.logging.opentracing import trace
 from synapse.storage.databases.main.relations import _RelatedEvent
 from synapse.types import JsonDict, Requester, StreamToken, UserID
 from synapse.visibility import filter_events_for_client
@@ -73,7 +74,6 @@ class RelationsHandler:
         room_id: str,
         relation_type: Optional[str] = None,
         event_type: Optional[str] = None,
-        aggregation_key: Optional[str] = None,
         limit: int = 5,
         direction: str = "b",
         from_token: Optional[StreamToken] = None,
@@ -89,7 +89,6 @@ class RelationsHandler:
             room_id: The room the event belongs to.
             relation_type: Only fetch events with this relation type, if given.
             event_type: Only fetch events with this event type, if given.
-            aggregation_key: Only fetch events with this aggregation key, if given.
             limit: Only fetch the most recent `limit` events.
             direction: Whether to fetch the most recent first (`"b"`) or the
                 oldest first (`"f"`).
@@ -104,7 +103,7 @@ class RelationsHandler:
 
         # TODO Properly handle a user leaving a room.
         (_, member_event_id) = await self._auth.check_user_in_room_or_world_readable(
-            room_id, user_id, allow_departed_users=True
+            room_id, requester, allow_departed_users=True
         )
 
         # This gets the original event and checks that a) the event exists and
@@ -122,7 +121,6 @@ class RelationsHandler:
             room_id=room_id,
             relation_type=relation_type,
             event_type=event_type,
-            aggregation_key=aggregation_key,
             limit=limit,
             direction=direction,
             from_token=from_token,
@@ -364,6 +362,7 @@ class RelationsHandler:
 
         return results
 
+    @trace
     async def get_bundled_aggregations(
         self, events: Iterable[EventBase], user_id: str
     ) -> Dict[str, BundledAggregations]:
diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py
index 978d3ee39f..2bf0ebd025 100644
--- a/synapse/handlers/room.py
+++ b/synapse/handlers/room.py
@@ -721,7 +721,7 @@ class RoomCreationHandler:
             # allow the server notices mxid to create rooms
             is_requester_admin = True
         else:
-            is_requester_admin = await self.auth.is_server_admin(requester.user)
+            is_requester_admin = await self.auth.is_server_admin(requester)
 
         # Let the third party rules modify the room creation config if needed, or abort
         # the room creation entirely with an exception.
@@ -1279,7 +1279,7 @@ class RoomContextHandler:
         """
         user = requester.user
         if use_admin_priviledge:
-            await assert_user_is_admin(self.auth, requester.user)
+            await assert_user_is_admin(self.auth, requester)
 
         before_limit = math.floor(limit / 2.0)
         after_limit = limit - before_limit
@@ -1384,6 +1384,7 @@ class TimestampLookupHandler:
         self.store = hs.get_datastores().main
         self.state_handler = hs.get_state_handler()
         self.federation_client = hs.get_federation_client()
+        self.federation_event_handler = hs.get_federation_event_handler()
         self._storage_controllers = hs.get_storage_controllers()
 
     async def get_event_for_timestamp(
@@ -1479,38 +1480,68 @@ class TimestampLookupHandler:
                         remote_response,
                     )
 
-                    # TODO: Do we want to persist this as an extremity?
-                    # TODO: I think ideally, we would try to backfill from
-                    # this event and run this whole
-                    # `get_event_for_timestamp` function again to make sure
-                    # they didn't give us an event from their gappy history.
                     remote_event_id = remote_response.event_id
-                    origin_server_ts = remote_response.origin_server_ts
+                    remote_origin_server_ts = remote_response.origin_server_ts
+
+                    # Backfill this event so we can get a pagination token for
+                    # it with `/context` and paginate `/messages` from this
+                    # point.
+                    #
+                    # TODO: The requested timestamp may lie in a part of the
+                    #   event graph that the remote server *also* didn't have,
+                    #   in which case they will have returned another event
+                    #   which may be nowhere near the requested timestamp. In
+                    #   the future, we may need to reconcile that gap and ask
+                    #   other homeservers, and/or extend `/timestamp_to_event`
+                    #   to return events on *both* sides of the timestamp to
+                    #   help reconcile the gap faster.
+                    remote_event = (
+                        await self.federation_event_handler.backfill_event_id(
+                            domain, room_id, remote_event_id
+                        )
+                    )
+
+                    # XXX: When we see that the remote server is not trustworthy,
+                    # maybe we should not ask them first in the future.
+                    if remote_origin_server_ts != remote_event.origin_server_ts:
+                        logger.info(
+                            "get_event_for_timestamp: Remote server (%s) claimed that remote_event_id=%s occured at remote_origin_server_ts=%s but that isn't true (actually occured at %s). Their claims are dubious and we should consider not trusting them.",
+                            domain,
+                            remote_event_id,
+                            remote_origin_server_ts,
+                            remote_event.origin_server_ts,
+                        )
 
                     # Only return the remote event if it's closer than the local event
                     if not local_event or (
-                        abs(origin_server_ts - timestamp)
+                        abs(remote_event.origin_server_ts - timestamp)
                         < abs(local_event.origin_server_ts - timestamp)
                     ):
-                        return remote_event_id, origin_server_ts
+                        logger.info(
+                            "get_event_for_timestamp: returning remote_event_id=%s (%s) since it's closer to timestamp=%s than local_event=%s (%s)",
+                            remote_event_id,
+                            remote_event.origin_server_ts,
+                            timestamp,
+                            local_event.event_id if local_event else None,
+                            local_event.origin_server_ts if local_event else None,
+                        )
+                        return remote_event_id, remote_origin_server_ts
                 except (HttpResponseException, InvalidResponseError) as ex:
                     # Let's not put a high priority on some other homeserver
                     # failing to respond or giving a random response
                     logger.debug(
-                        "Failed to fetch /timestamp_to_event from %s because of exception(%s) %s args=%s",
+                        "get_event_for_timestamp: Failed to fetch /timestamp_to_event from %s because of exception(%s) %s args=%s",
                         domain,
                         type(ex).__name__,
                         ex,
                         ex.args,
                     )
-                except Exception as ex:
+                except Exception:
                     # But we do want to see some exceptions in our code
                     logger.warning(
-                        "Failed to fetch /timestamp_to_event from %s because of exception(%s) %s args=%s",
+                        "get_event_for_timestamp: Failed to fetch /timestamp_to_event from %s because of exception",
                         domain,
-                        type(ex).__name__,
-                        ex,
-                        ex.args,
+                        exc_info=True,
                     )
 
         # To appease mypy, we have to add both of these conditions to check for
diff --git a/synapse/handlers/room_list.py b/synapse/handlers/room_list.py
index 29868eb743..bb0bdb8e6f 100644
--- a/synapse/handlers/room_list.py
+++ b/synapse/handlers/room_list.py
@@ -182,7 +182,7 @@ class RoomListHandler:
                 == HistoryVisibility.WORLD_READABLE,
                 "guest_can_join": room["guest_access"] == "can_join",
                 "join_rule": room["join_rules"],
-                "org.matrix.msc3827.room_type": room["room_type"],
+                "room_type": room["room_type"],
             }
 
             # Filter out Nones – rather omit the field altogether
diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py
index ef2fa6bb6f..9c0fdeca15 100644
--- a/synapse/handlers/room_member.py
+++ b/synapse/handlers/room_member.py
@@ -32,6 +32,7 @@ from synapse.event_auth import get_named_level, get_power_level_event
 from synapse.events import EventBase
 from synapse.events.snapshot import EventContext
 from synapse.handlers.profile import MAX_AVATAR_URL_LEN, MAX_DISPLAYNAME_LEN
+from synapse.logging import opentracing
 from synapse.module_api import NOT_SPAM
 from synapse.storage.state import StateFilter
 from synapse.types import (
@@ -178,7 +179,7 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
         """Try and join a room that this server is not in
 
         Args:
-            requester
+            requester: The user making the request, according to the access token.
             remote_room_hosts: List of servers that can be used to join via.
             room_id: Room that we are trying to join
             user: User who is trying to join
@@ -430,14 +431,14 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
                 await self._join_rate_per_room_limiter.ratelimit(
                     requester, key=room_id, update=False
                 )
-
-        result_event = await self.event_creation_handler.handle_new_client_event(
-            requester,
-            event,
-            context,
-            extra_users=[target],
-            ratelimit=ratelimit,
-        )
+        with opentracing.start_active_span("handle_new_client_event"):
+            result_event = await self.event_creation_handler.handle_new_client_event(
+                requester,
+                event,
+                context,
+                extra_users=[target],
+                ratelimit=ratelimit,
+            )
 
         if event.membership == Membership.LEAVE:
             if prev_member_event_id:
@@ -566,25 +567,26 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
         # by application services), and then by room ID.
         async with self.member_as_limiter.queue(as_id):
             async with self.member_linearizer.queue(key):
-                result = await self.update_membership_locked(
-                    requester,
-                    target,
-                    room_id,
-                    action,
-                    txn_id=txn_id,
-                    remote_room_hosts=remote_room_hosts,
-                    third_party_signed=third_party_signed,
-                    ratelimit=ratelimit,
-                    content=content,
-                    new_room=new_room,
-                    require_consent=require_consent,
-                    outlier=outlier,
-                    historical=historical,
-                    allow_no_prev_events=allow_no_prev_events,
-                    prev_event_ids=prev_event_ids,
-                    state_event_ids=state_event_ids,
-                    depth=depth,
-                )
+                with opentracing.start_active_span("update_membership_locked"):
+                    result = await self.update_membership_locked(
+                        requester,
+                        target,
+                        room_id,
+                        action,
+                        txn_id=txn_id,
+                        remote_room_hosts=remote_room_hosts,
+                        third_party_signed=third_party_signed,
+                        ratelimit=ratelimit,
+                        content=content,
+                        new_room=new_room,
+                        require_consent=require_consent,
+                        outlier=outlier,
+                        historical=historical,
+                        allow_no_prev_events=allow_no_prev_events,
+                        prev_event_ids=prev_event_ids,
+                        state_event_ids=state_event_ids,
+                        depth=depth,
+                    )
 
         return result
 
@@ -651,6 +653,7 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
         Returns:
             A tuple of the new event ID and stream ID.
         """
+
         content_specified = bool(content)
         if content is None:
             content = {}
@@ -688,7 +691,7 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
                 errcode=Codes.BAD_JSON,
             )
 
-        if "avatar_url" in content:
+        if "avatar_url" in content and content.get("avatar_url") is not None:
             if not await self.profile_handler.check_avatar_size_and_mime_type(
                 content["avatar_url"],
             ):
@@ -743,7 +746,7 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
                 is_requester_admin = True
 
             else:
-                is_requester_admin = await self.auth.is_server_admin(requester.user)
+                is_requester_admin = await self.auth.is_server_admin(requester)
 
             if not is_requester_admin:
                 if self.config.server.block_non_admin_invites:
@@ -878,7 +881,7 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
                 bypass_spam_checker = True
 
             else:
-                bypass_spam_checker = await self.auth.is_server_admin(requester.user)
+                bypass_spam_checker = await self.auth.is_server_admin(requester)
 
             inviter = await self._get_inviter(target.to_string(), room_id)
             if (
@@ -1438,7 +1441,7 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
             ShadowBanError if the requester has been shadow-banned.
         """
         if self.config.server.block_non_admin_invites:
-            is_requester_admin = await self.auth.is_server_admin(requester.user)
+            is_requester_admin = await self.auth.is_server_admin(requester)
             if not is_requester_admin:
                 raise SynapseError(
                     403, "Invites have been disabled on this server", Codes.FORBIDDEN
@@ -1710,14 +1713,18 @@ class RoomMemberMasterHandler(RoomMemberHandler):
         ]
 
         if len(remote_room_hosts) == 0:
-            raise SynapseError(404, "No known servers")
+            raise SynapseError(
+                404,
+                "Can't join remote room because no servers "
+                "that are in the room have been provided.",
+            )
 
         check_complexity = self.hs.config.server.limit_remote_rooms.enabled
         if (
             check_complexity
             and self.hs.config.server.limit_remote_rooms.admins_can_join
         ):
-            check_complexity = not await self.auth.is_server_admin(user)
+            check_complexity = not await self.store.is_server_admin(user)
 
         if check_complexity:
             # Fetch the room complexity
diff --git a/synapse/handlers/room_summary.py b/synapse/handlers/room_summary.py
index 13098f56ed..732b0310bc 100644
--- a/synapse/handlers/room_summary.py
+++ b/synapse/handlers/room_summary.py
@@ -28,11 +28,11 @@ from synapse.api.constants import (
     RoomTypes,
 )
 from synapse.api.errors import (
-    AuthError,
     Codes,
     NotFoundError,
     StoreError,
     SynapseError,
+    UnstableSpecAuthError,
     UnsupportedRoomVersionError,
 )
 from synapse.api.ratelimiting import Ratelimiter
@@ -175,10 +175,11 @@ class RoomSummaryHandler:
 
         # First of all, check that the room is accessible.
         if not await self._is_local_room_accessible(requested_room_id, requester):
-            raise AuthError(
+            raise UnstableSpecAuthError(
                 403,
                 "User %s not in room %s, and room previews are disabled"
                 % (requester, requested_room_id),
+                errcode=Codes.NOT_JOINED,
             )
 
         # If this is continuing a previous session, pull the persisted data.
diff --git a/synapse/handlers/send_email.py b/synapse/handlers/send_email.py
index a305a66860..e2844799e8 100644
--- a/synapse/handlers/send_email.py
+++ b/synapse/handlers/send_email.py
@@ -23,10 +23,12 @@ from pkg_resources import parse_version
 
 import twisted
 from twisted.internet.defer import Deferred
-from twisted.internet.interfaces import IOpenSSLContextFactory, IReactorTCP
+from twisted.internet.interfaces import IOpenSSLContextFactory
+from twisted.internet.ssl import optionsForClientTLS
 from twisted.mail.smtp import ESMTPSender, ESMTPSenderFactory
 
 from synapse.logging.context import make_deferred_yieldable
+from synapse.types import ISynapseReactor
 
 if TYPE_CHECKING:
     from synapse.server import HomeServer
@@ -48,7 +50,7 @@ class _NoTLSESMTPSender(ESMTPSender):
 
 
 async def _sendmail(
-    reactor: IReactorTCP,
+    reactor: ISynapseReactor,
     smtphost: str,
     smtpport: int,
     from_addr: str,
@@ -59,6 +61,7 @@ async def _sendmail(
     require_auth: bool = False,
     require_tls: bool = False,
     enable_tls: bool = True,
+    force_tls: bool = False,
 ) -> None:
     """A simple wrapper around ESMTPSenderFactory, to allow substitution in tests
 
@@ -73,8 +76,9 @@ async def _sendmail(
         password: password to give when authenticating
         require_auth: if auth is not offered, fail the request
         require_tls: if TLS is not offered, fail the reqest
-        enable_tls: True to enable TLS. If this is False and require_tls is True,
+        enable_tls: True to enable STARTTLS. If this is False and require_tls is True,
            the request will fail.
+        force_tls: True to enable Implicit TLS.
     """
     msg = BytesIO(msg_bytes)
     d: "Deferred[object]" = Deferred()
@@ -105,13 +109,23 @@ async def _sendmail(
         # set to enable TLS.
         factory = build_sender_factory(hostname=smtphost if enable_tls else None)
 
-    reactor.connectTCP(
-        smtphost,
-        smtpport,
-        factory,
-        timeout=30,
-        bindAddress=None,
-    )
+    if force_tls:
+        reactor.connectSSL(
+            smtphost,
+            smtpport,
+            factory,
+            optionsForClientTLS(smtphost),
+            timeout=30,
+            bindAddress=None,
+        )
+    else:
+        reactor.connectTCP(
+            smtphost,
+            smtpport,
+            factory,
+            timeout=30,
+            bindAddress=None,
+        )
 
     await make_deferred_yieldable(d)
 
@@ -132,6 +146,7 @@ class SendEmailHandler:
         self._smtp_pass = passwd.encode("utf-8") if passwd is not None else None
         self._require_transport_security = hs.config.email.require_transport_security
         self._enable_tls = hs.config.email.enable_smtp_tls
+        self._force_tls = hs.config.email.force_tls
 
         self._sendmail = _sendmail
 
@@ -189,4 +204,5 @@ class SendEmailHandler:
             require_auth=self._smtp_user is not None,
             require_tls=self._require_transport_security,
             enable_tls=self._enable_tls,
+            force_tls=self._force_tls,
         )
diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index d42a414c90..2d95b1fa24 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -13,7 +13,19 @@
 # limitations under the License.
 import itertools
 import logging
-from typing import TYPE_CHECKING, Any, Dict, FrozenSet, List, Optional, Set, Tuple
+from typing import (
+    TYPE_CHECKING,
+    Any,
+    Collection,
+    Dict,
+    FrozenSet,
+    List,
+    Mapping,
+    Optional,
+    Sequence,
+    Set,
+    Tuple,
+)
 
 import attr
 from prometheus_client import Counter
@@ -89,7 +101,7 @@ class SyncConfig:
 @attr.s(slots=True, frozen=True, auto_attribs=True)
 class TimelineBatch:
     prev_batch: StreamToken
-    events: List[EventBase]
+    events: Sequence[EventBase]
     limited: bool
     # A mapping of event ID to the bundled aggregations for the above events.
     # This is only calculated if limited is true.
@@ -507,10 +519,17 @@ class SyncHandler:
                 # ensure that we always include current state in the timeline
                 current_state_ids: FrozenSet[str] = frozenset()
                 if any(e.is_state() for e in recents):
+                    # FIXME(faster_joins): We use the partial state here as
+                    # we don't want to block `/sync` on finishing a lazy join.
+                    # Which should be fine once
+                    # https://github.com/matrix-org/synapse/issues/12989 is resolved,
+                    # since we shouldn't reach here anymore?
+                    # Note that we use the current state as a whitelist for filtering
+                    # `recents`, so partial state is only a problem when a membership
+                    # event turns up in `recents` but has not made it into the current
+                    # state.
                     current_state_ids_map = (
-                        await self._state_storage_controller.get_current_state_ids(
-                            room_id
-                        )
+                        await self.store.get_partial_current_state_ids(room_id)
                     )
                     current_state_ids = frozenset(current_state_ids_map.values())
 
@@ -579,7 +598,13 @@ class SyncHandler:
                 if any(e.is_state() for e in loaded_recents):
                     # FIXME(faster_joins): We use the partial state here as
                     # we don't want to block `/sync` on finishing a lazy join.
-                    # Is this the correct way of doing it?
+                    # Which should be fine once
+                    # https://github.com/matrix-org/synapse/issues/12989 is resolved,
+                    # since we shouldn't reach here anymore?
+                    # Note that we use the current state as a whitelist for filtering
+                    # `loaded_recents`, so partial state is only a problem when a
+                    # membership event turns up in `loaded_recents` but has not made it
+                    # into the current state.
                     current_state_ids_map = (
                         await self.store.get_partial_current_state_ids(room_id)
                     )
@@ -627,7 +652,10 @@ class SyncHandler:
         )
 
     async def get_state_after_event(
-        self, event_id: str, state_filter: Optional[StateFilter] = None
+        self,
+        event_id: str,
+        state_filter: Optional[StateFilter] = None,
+        await_full_state: bool = True,
     ) -> StateMap[str]:
         """
         Get the room state after the given event
@@ -635,9 +663,14 @@ class SyncHandler:
         Args:
             event_id: event of interest
             state_filter: The state filter used to fetch state from the database.
+            await_full_state: if `True`, will block if we do not yet have complete state
+                at the event and `state_filter` is not satisfied by partial state.
+                Defaults to `True`.
         """
         state_ids = await self._state_storage_controller.get_state_ids_for_event(
-            event_id, state_filter=state_filter or StateFilter.all()
+            event_id,
+            state_filter=state_filter or StateFilter.all(),
+            await_full_state=await_full_state,
         )
 
         # using get_metadata_for_events here (instead of get_event) sidesteps an issue
@@ -660,6 +693,7 @@ class SyncHandler:
         room_id: str,
         stream_position: StreamToken,
         state_filter: Optional[StateFilter] = None,
+        await_full_state: bool = True,
     ) -> StateMap[str]:
         """Get the room state at a particular stream position
 
@@ -667,6 +701,9 @@ class SyncHandler:
             room_id: room for which to get state
             stream_position: point at which to get state
             state_filter: The state filter used to fetch state from the database.
+            await_full_state: if `True`, will block if we do not yet have complete state
+                at the last event in the room before `stream_position` and
+                `state_filter` is not satisfied by partial state. Defaults to `True`.
         """
         # FIXME: This gets the state at the latest event before the stream ordering,
         # which might not be the same as the "current state" of the room at the time
@@ -678,7 +715,9 @@ class SyncHandler:
 
         if last_event_id:
             state = await self.get_state_after_event(
-                last_event_id, state_filter=state_filter or StateFilter.all()
+                last_event_id,
+                state_filter=state_filter or StateFilter.all(),
+                await_full_state=await_full_state,
             )
 
         else:
@@ -852,16 +891,26 @@ class SyncHandler:
         now_token: StreamToken,
         full_state: bool,
     ) -> MutableStateMap[EventBase]:
-        """Works out the difference in state between the start of the timeline
-        and the previous sync.
+        """Works out the difference in state between the end of the previous sync and
+        the start of the timeline.
 
         Args:
             room_id:
             batch: The timeline batch for the room that will be sent to the user.
             sync_config:
-            since_token: Token of the end of the previous batch. May be None.
+            since_token: Token of the end of the previous batch. May be `None`.
             now_token: Token of the end of the current batch.
             full_state: Whether to force returning the full state.
+                `lazy_load_members` still applies when `full_state` is `True`.
+
+        Returns:
+            The state to return in the sync response for the room.
+
+            Clients will overlay this onto the state at the end of the previous sync to
+            arrive at the state at the start of the timeline.
+
+            Clients will then overlay state events in the timeline to arrive at the
+            state at the end of the timeline, in preparation for the next sync.
         """
         # TODO(mjark) Check if the state events were received by the server
         # after the previous sync, since we need to include those state
@@ -869,8 +918,17 @@ class SyncHandler:
         # TODO(mjark) Check for new redactions in the state events.
 
         with Measure(self.clock, "compute_state_delta"):
+            # The memberships needed for events in the timeline.
+            # Only calculated when `lazy_load_members` is on.
+            members_to_fetch: Optional[Set[str]] = None
+
+            # A dictionary mapping user IDs to the first event in the timeline sent by
+            # them. Only calculated when `lazy_load_members` is on.
+            first_event_by_sender_map: Optional[Dict[str, EventBase]] = None
 
-            members_to_fetch = None
+            # The contribution to the room state from state events in the timeline.
+            # Only contains the last event for any given state key.
+            timeline_state: StateMap[str]
 
             lazy_load_members = sync_config.filter_collection.lazy_load_members()
             include_redundant_members = (
@@ -881,10 +939,23 @@ class SyncHandler:
                 # We only request state for the members needed to display the
                 # timeline:
 
-                members_to_fetch = {
-                    event.sender  # FIXME: we also care about invite targets etc.
-                    for event in batch.events
-                }
+                timeline_state = {}
+
+                members_to_fetch = set()
+                first_event_by_sender_map = {}
+                for event in batch.events:
+                    # Build the map from user IDs to the first timeline event they sent.
+                    if event.sender not in first_event_by_sender_map:
+                        first_event_by_sender_map[event.sender] = event
+
+                    # We need the event's sender, unless their membership was in a
+                    # previous timeline event.
+                    if (EventTypes.Member, event.sender) not in timeline_state:
+                        members_to_fetch.add(event.sender)
+                    # FIXME: we also care about invite targets etc.
+
+                    if event.is_state():
+                        timeline_state[(event.type, event.state_key)] = event.event_id
 
                 if full_state:
                     # always make sure we LL ourselves so we know we're in the room
@@ -894,55 +965,80 @@ class SyncHandler:
                     members_to_fetch.add(sync_config.user.to_string())
 
                 state_filter = StateFilter.from_lazy_load_member_list(members_to_fetch)
+
+                # We are happy to use partial state to compute the `/sync` response.
+                # Since partial state may not include the lazy-loaded memberships we
+                # require, we fix up the state response afterwards with memberships from
+                # auth events.
+                await_full_state = False
             else:
+                timeline_state = {
+                    (event.type, event.state_key): event.event_id
+                    for event in batch.events
+                    if event.is_state()
+                }
+
                 state_filter = StateFilter.all()
+                await_full_state = True
 
-            timeline_state = {
-                (event.type, event.state_key): event.event_id
-                for event in batch.events
-                if event.is_state()
-            }
+            # Now calculate the state to return in the sync response for the room.
+            # This is more or less the change in state between the end of the previous
+            # sync's timeline and the start of the current sync's timeline.
+            # See the docstring above for details.
+            state_ids: StateMap[str]
 
             if full_state:
                 if batch:
-                    current_state_ids = (
+                    state_at_timeline_end = (
                         await self._state_storage_controller.get_state_ids_for_event(
-                            batch.events[-1].event_id, state_filter=state_filter
+                            batch.events[-1].event_id,
+                            state_filter=state_filter,
+                            await_full_state=await_full_state,
                         )
                     )
 
-                    state_ids = (
+                    state_at_timeline_start = (
                         await self._state_storage_controller.get_state_ids_for_event(
-                            batch.events[0].event_id, state_filter=state_filter
+                            batch.events[0].event_id,
+                            state_filter=state_filter,
+                            await_full_state=await_full_state,
                         )
                     )
 
                 else:
-                    current_state_ids = await self.get_state_at(
-                        room_id, stream_position=now_token, state_filter=state_filter
+                    state_at_timeline_end = await self.get_state_at(
+                        room_id,
+                        stream_position=now_token,
+                        state_filter=state_filter,
+                        await_full_state=await_full_state,
                     )
 
-                    state_ids = current_state_ids
+                    state_at_timeline_start = state_at_timeline_end
 
                 state_ids = _calculate_state(
                     timeline_contains=timeline_state,
-                    timeline_start=state_ids,
-                    previous={},
-                    current=current_state_ids,
+                    timeline_start=state_at_timeline_start,
+                    timeline_end=state_at_timeline_end,
+                    previous_timeline_end={},
                     lazy_load_members=lazy_load_members,
                 )
             elif batch.limited:
                 if batch:
                     state_at_timeline_start = (
                         await self._state_storage_controller.get_state_ids_for_event(
-                            batch.events[0].event_id, state_filter=state_filter
+                            batch.events[0].event_id,
+                            state_filter=state_filter,
+                            await_full_state=await_full_state,
                         )
                     )
                 else:
                     # We can get here if the user has ignored the senders of all
                     # the recent events.
                     state_at_timeline_start = await self.get_state_at(
-                        room_id, stream_position=now_token, state_filter=state_filter
+                        room_id,
+                        stream_position=now_token,
+                        state_filter=state_filter,
+                        await_full_state=await_full_state,
                     )
 
                 # for now, we disable LL for gappy syncs - see
@@ -964,28 +1060,35 @@ class SyncHandler:
                 # is indeed the case.
                 assert since_token is not None
                 state_at_previous_sync = await self.get_state_at(
-                    room_id, stream_position=since_token, state_filter=state_filter
+                    room_id,
+                    stream_position=since_token,
+                    state_filter=state_filter,
+                    await_full_state=await_full_state,
                 )
 
                 if batch:
-                    current_state_ids = (
+                    state_at_timeline_end = (
                         await self._state_storage_controller.get_state_ids_for_event(
-                            batch.events[-1].event_id, state_filter=state_filter
+                            batch.events[-1].event_id,
+                            state_filter=state_filter,
+                            await_full_state=await_full_state,
                         )
                     )
                 else:
-                    # Its not clear how we get here, but empirically we do
-                    # (#5407). Logging has been added elsewhere to try and
-                    # figure out where this state comes from.
-                    current_state_ids = await self.get_state_at(
-                        room_id, stream_position=now_token, state_filter=state_filter
+                    # We can get here if the user has ignored the senders of all
+                    # the recent events.
+                    state_at_timeline_end = await self.get_state_at(
+                        room_id,
+                        stream_position=now_token,
+                        state_filter=state_filter,
+                        await_full_state=await_full_state,
                     )
 
                 state_ids = _calculate_state(
                     timeline_contains=timeline_state,
                     timeline_start=state_at_timeline_start,
-                    previous=state_at_previous_sync,
-                    current=current_state_ids,
+                    timeline_end=state_at_timeline_end,
+                    previous_timeline_end=state_at_previous_sync,
                     # we have to include LL members in case LL initial sync missed them
                     lazy_load_members=lazy_load_members,
                 )
@@ -1008,8 +1111,30 @@ class SyncHandler:
                                 (EventTypes.Member, member)
                                 for member in members_to_fetch
                             ),
+                            await_full_state=False,
                         )
 
+            # If we only have partial state for the room, `state_ids` may be missing the
+            # memberships we wanted. We attempt to find some by digging through the auth
+            # events of timeline events.
+            if lazy_load_members and await self.store.is_partial_state_room(room_id):
+                assert members_to_fetch is not None
+                assert first_event_by_sender_map is not None
+
+                additional_state_ids = (
+                    await self._find_missing_partial_state_memberships(
+                        room_id, members_to_fetch, first_event_by_sender_map, state_ids
+                    )
+                )
+                state_ids = {**state_ids, **additional_state_ids}
+
+            # At this point, if `lazy_load_members` is enabled, `state_ids` includes
+            # the memberships of all event senders in the timeline. This is because we
+            # may not have sent the memberships in a previous sync.
+
+            # When `include_redundant_members` is on, we send all the lazy-loaded
+            # memberships of event senders. Otherwise we make an effort to limit the set
+            # of memberships we send to those that we have not already sent to this client.
             if lazy_load_members and not include_redundant_members:
                 cache_key = (sync_config.user.to_string(), sync_config.device_id)
                 cache = self.get_lazy_loaded_members_cache(cache_key)
@@ -1051,6 +1176,99 @@ class SyncHandler:
             if e.type != EventTypes.Aliases  # until MSC2261 or alternative solution
         }
 
+    async def _find_missing_partial_state_memberships(
+        self,
+        room_id: str,
+        members_to_fetch: Collection[str],
+        events_with_membership_auth: Mapping[str, EventBase],
+        found_state_ids: StateMap[str],
+    ) -> StateMap[str]:
+        """Finds missing memberships from a set of auth events and returns them as a
+        state map.
+
+        Args:
+            room_id: The partial state room to find the remaining memberships for.
+            members_to_fetch: The memberships to find.
+            events_with_membership_auth: A mapping from user IDs to events whose auth
+                events are known to contain their membership.
+            found_state_ids: A dict from (type, state_key) -> state_event_id, containing
+                memberships that have been previously found. Entries in
+                `members_to_fetch` that have a membership in `found_state_ids` are
+                ignored.
+
+        Returns:
+            A dict from ("m.room.member", state_key) -> state_event_id, containing the
+            memberships missing from `found_state_ids`.
+
+        Raises:
+            KeyError: if `events_with_membership_auth` does not have an entry for a
+                missing membership. Memberships in `found_state_ids` do not need an
+                entry in `events_with_membership_auth`.
+        """
+        additional_state_ids: MutableStateMap[str] = {}
+
+        # Tracks the missing members for logging purposes.
+        missing_members = set()
+
+        # Identify memberships missing from `found_state_ids` and pick out the auth
+        # events in which to look for them.
+        auth_event_ids: Set[str] = set()
+        for member in members_to_fetch:
+            if (EventTypes.Member, member) in found_state_ids:
+                continue
+
+            missing_members.add(member)
+            event_with_membership_auth = events_with_membership_auth[member]
+            auth_event_ids.update(event_with_membership_auth.auth_event_ids())
+
+        auth_events = await self.store.get_events(auth_event_ids)
+
+        # Run through the missing memberships once more, picking out the memberships
+        # from the pile of auth events we have just fetched.
+        for member in members_to_fetch:
+            if (EventTypes.Member, member) in found_state_ids:
+                continue
+
+            event_with_membership_auth = events_with_membership_auth[member]
+
+            # Dig through the auth events to find the desired membership.
+            for auth_event_id in event_with_membership_auth.auth_event_ids():
+                # We only store events once we have all their auth events,
+                # so the auth event must be in the pile we have just
+                # fetched.
+                auth_event = auth_events[auth_event_id]
+
+                if (
+                    auth_event.type == EventTypes.Member
+                    and auth_event.state_key == member
+                ):
+                    missing_members.remove(member)
+                    additional_state_ids[
+                        (EventTypes.Member, member)
+                    ] = auth_event.event_id
+                    break
+
+        if missing_members:
+            # There really shouldn't be any missing memberships now. Either:
+            #  * we couldn't find an auth event, which shouldn't happen because we do
+            #    not persist events with persisting their auth events first, or
+            #  * the set of auth events did not contain a membership we wanted, which
+            #    means our caller didn't compute the events in `members_to_fetch`
+            #    correctly, or we somehow accepted an event whose auth events were
+            #    dodgy.
+            logger.error(
+                "Failed to find memberships for %s in partial state room "
+                "%s in the auth events of %s.",
+                missing_members,
+                room_id,
+                [
+                    events_with_membership_auth[member].event_id
+                    for member in missing_members
+                ],
+            )
+
+        return additional_state_ids
+
     async def unread_notifs_for_room_id(
         self, room_id: str, sync_config: SyncConfig
     ) -> NotifCounts:
@@ -1536,15 +1754,13 @@ class SyncHandler:
         ignored_users = await self.store.ignored_users(user_id)
         if since_token:
             room_changes = await self._get_rooms_changed(
-                sync_result_builder, ignored_users, self.rooms_to_exclude
+                sync_result_builder, ignored_users
             )
             tags_by_room = await self.store.get_updated_tags(
                 user_id, since_token.account_data_key
             )
         else:
-            room_changes = await self._get_all_rooms(
-                sync_result_builder, ignored_users, self.rooms_to_exclude
-            )
+            room_changes = await self._get_all_rooms(sync_result_builder, ignored_users)
             tags_by_room = await self.store.get_tags_for_user(user_id)
 
         log_kv({"rooms_changed": len(room_changes.room_entries)})
@@ -1623,13 +1839,14 @@ class SyncHandler:
         self,
         sync_result_builder: "SyncResultBuilder",
         ignored_users: FrozenSet[str],
-        excluded_rooms: List[str],
     ) -> _RoomChanges:
         """Determine the changes in rooms to report to the user.
 
         This function is a first pass at generating the rooms part of the sync response.
         It determines which rooms have changed during the sync period, and categorises
-        them into four buckets: "knock", "invite", "join" and "leave".
+        them into four buckets: "knock", "invite", "join" and "leave". It also excludes
+        from that list any room that appears in the list of rooms to exclude from sync
+        results in the server configuration.
 
         1. Finds all membership changes for the user in the sync period (from
            `since_token` up to `now_token`).
@@ -1655,7 +1872,7 @@ class SyncHandler:
         #       _have_rooms_changed. We could keep the results in memory to avoid a
         #       second query, at the cost of more complicated source code.
         membership_change_events = await self.store.get_membership_changes_for_user(
-            user_id, since_token.room_key, now_token.room_key, excluded_rooms
+            user_id, since_token.room_key, now_token.room_key, self.rooms_to_exclude
         )
 
         mem_change_events_by_room_id: Dict[str, List[EventBase]] = {}
@@ -1696,7 +1913,11 @@ class SyncHandler:
                 continue
 
             if room_id in sync_result_builder.joined_room_ids or has_join:
-                old_state_ids = await self.get_state_at(room_id, since_token)
+                old_state_ids = await self.get_state_at(
+                    room_id,
+                    since_token,
+                    state_filter=StateFilter.from_types([(EventTypes.Member, user_id)]),
+                )
                 old_mem_ev_id = old_state_ids.get((EventTypes.Member, user_id), None)
                 old_mem_ev = None
                 if old_mem_ev_id:
@@ -1722,7 +1943,13 @@ class SyncHandler:
                     newly_left_rooms.append(room_id)
                 else:
                     if not old_state_ids:
-                        old_state_ids = await self.get_state_at(room_id, since_token)
+                        old_state_ids = await self.get_state_at(
+                            room_id,
+                            since_token,
+                            state_filter=StateFilter.from_types(
+                                [(EventTypes.Member, user_id)]
+                            ),
+                        )
                         old_mem_ev_id = old_state_ids.get(
                             (EventTypes.Member, user_id), None
                         )
@@ -1862,7 +2089,6 @@ class SyncHandler:
         self,
         sync_result_builder: "SyncResultBuilder",
         ignored_users: FrozenSet[str],
-        ignored_rooms: List[str],
     ) -> _RoomChanges:
         """Returns entries for all rooms for the user.
 
@@ -1884,7 +2110,7 @@ class SyncHandler:
         room_list = await self.store.get_rooms_for_local_user_where_membership_is(
             user_id=user_id,
             membership_list=Membership.LIST,
-            excluded_rooms=ignored_rooms,
+            excluded_rooms=self.rooms_to_exclude,
         )
 
         room_entries = []
@@ -2150,7 +2376,9 @@ class SyncHandler:
                 raise Exception("Unrecognized rtype: %r", room_builder.rtype)
 
     async def get_rooms_for_user_at(
-        self, user_id: str, room_key: RoomStreamToken
+        self,
+        user_id: str,
+        room_key: RoomStreamToken,
     ) -> FrozenSet[str]:
         """Get set of joined rooms for a user at the given stream ordering.
 
@@ -2176,7 +2404,12 @@ class SyncHandler:
         # If the membership's stream ordering is after the given stream
         # ordering, we need to go and work out if the user was in the room
         # before.
+        # We also need to check whether the room should be excluded from sync
+        # responses as per the homeserver config.
         for joined_room in joined_rooms:
+            if joined_room.room_id in self.rooms_to_exclude:
+                continue
+
             if not joined_room.event_pos.persisted_after(room_key):
                 joined_room_ids.add(joined_room.room_id)
                 continue
@@ -2188,10 +2421,10 @@ class SyncHandler:
                     joined_room.room_id, joined_room.event_pos.stream
                 )
             )
-            users_in_room = await self.state.get_current_users_in_room(
+            user_ids_in_room = await self.state.get_current_user_ids_in_room(
                 joined_room.room_id, extrems
             )
-            if user_id in users_in_room:
+            if user_id in user_ids_in_room:
                 joined_room_ids.add(joined_room.room_id)
 
         return frozenset(joined_room_ids)
@@ -2211,8 +2444,8 @@ def _action_has_highlight(actions: List[JsonDict]) -> bool:
 def _calculate_state(
     timeline_contains: StateMap[str],
     timeline_start: StateMap[str],
-    previous: StateMap[str],
-    current: StateMap[str],
+    timeline_end: StateMap[str],
+    previous_timeline_end: StateMap[str],
     lazy_load_members: bool,
 ) -> StateMap[str]:
     """Works out what state to include in a sync response.
@@ -2220,45 +2453,50 @@ def _calculate_state(
     Args:
         timeline_contains: state in the timeline
         timeline_start: state at the start of the timeline
-        previous: state at the end of the previous sync (or empty dict
+        timeline_end: state at the end of the timeline
+        previous_timeline_end: state at the end of the previous sync (or empty dict
             if this is an initial sync)
-        current: state at the end of the timeline
         lazy_load_members: whether to return members from timeline_start
             or not.  assumes that timeline_start has already been filtered to
             include only the members the client needs to know about.
     """
-    event_id_to_key = {
-        e: key
-        for key, e in itertools.chain(
+    event_id_to_state_key = {
+        event_id: state_key
+        for state_key, event_id in itertools.chain(
             timeline_contains.items(),
-            previous.items(),
             timeline_start.items(),
-            current.items(),
+            timeline_end.items(),
+            previous_timeline_end.items(),
         )
     }
 
-    c_ids = set(current.values())
-    ts_ids = set(timeline_start.values())
-    p_ids = set(previous.values())
-    tc_ids = set(timeline_contains.values())
+    timeline_end_ids = set(timeline_end.values())
+    timeline_start_ids = set(timeline_start.values())
+    previous_timeline_end_ids = set(previous_timeline_end.values())
+    timeline_contains_ids = set(timeline_contains.values())
 
     # If we are lazyloading room members, we explicitly add the membership events
     # for the senders in the timeline into the state block returned by /sync,
     # as we may not have sent them to the client before.  We find these membership
     # events by filtering them out of timeline_start, which has already been filtered
     # to only include membership events for the senders in the timeline.
-    # In practice, we can do this by removing them from the p_ids list,
-    # which is the list of relevant state we know we have already sent to the client.
+    # In practice, we can do this by removing them from the previous_timeline_end_ids
+    # list, which is the list of relevant state we know we have already sent to the
+    # client.
     # see https://github.com/matrix-org/synapse/pull/2970/files/efcdacad7d1b7f52f879179701c7e0d9b763511f#r204732809
 
     if lazy_load_members:
-        p_ids.difference_update(
+        previous_timeline_end_ids.difference_update(
             e for t, e in timeline_start.items() if t[0] == EventTypes.Member
         )
 
-    state_ids = ((c_ids | ts_ids) - p_ids) - tc_ids
+    state_ids = (
+        (timeline_end_ids | timeline_start_ids)
+        - previous_timeline_end_ids
+        - timeline_contains_ids
+    )
 
-    return {event_id_to_key[e]: e for e in state_ids}
+    return {event_id_to_state_key[e]: e for e in state_ids}
 
 
 @attr.s(slots=True, auto_attribs=True)
diff --git a/synapse/handlers/typing.py b/synapse/handlers/typing.py
index d104ea07fe..bcac3372a2 100644
--- a/synapse/handlers/typing.py
+++ b/synapse/handlers/typing.py
@@ -253,12 +253,11 @@ class TypingWriterHandler(FollowerTypingHandler):
         self, target_user: UserID, requester: Requester, room_id: str, timeout: int
     ) -> None:
         target_user_id = target_user.to_string()
-        auth_user_id = requester.user.to_string()
 
         if not self.is_mine_id(target_user_id):
             raise SynapseError(400, "User is not hosted on this homeserver")
 
-        if target_user_id != auth_user_id:
+        if target_user != requester.user:
             raise AuthError(400, "Cannot set another user's typing state")
 
         if requester.shadow_banned:
@@ -266,7 +265,7 @@ class TypingWriterHandler(FollowerTypingHandler):
             await self.clock.sleep(random.randint(1, 10))
             raise ShadowBanError()
 
-        await self.auth.check_user_in_room(room_id, target_user_id)
+        await self.auth.check_user_in_room(room_id, requester)
 
         logger.debug("%s has started typing in %s", target_user_id, room_id)
 
@@ -289,12 +288,11 @@ class TypingWriterHandler(FollowerTypingHandler):
         self, target_user: UserID, requester: Requester, room_id: str
     ) -> None:
         target_user_id = target_user.to_string()
-        auth_user_id = requester.user.to_string()
 
         if not self.is_mine_id(target_user_id):
             raise SynapseError(400, "User is not hosted on this homeserver")
 
-        if target_user_id != auth_user_id:
+        if target_user != requester.user:
             raise AuthError(400, "Cannot set another user's typing state")
 
         if requester.shadow_banned:
@@ -302,7 +300,7 @@ class TypingWriterHandler(FollowerTypingHandler):
             await self.clock.sleep(random.randint(1, 10))
             raise ShadowBanError()
 
-        await self.auth.check_user_in_room(room_id, target_user_id)
+        await self.auth.check_user_in_room(room_id, requester)
 
         logger.debug("%s has stopped typing in %s", target_user_id, room_id)
 
@@ -489,8 +487,15 @@ class TypingNotificationEventSource(EventSource[int, JsonDict]):
             handler = self.get_typing_handler()
 
             events = []
-            for room_id in handler._room_serials.keys():
-                if handler._room_serials[room_id] <= from_key:
+
+            # Work on a copy of things here as these may change in the handler while
+            # waiting for the AS `is_interested_in_room` call to complete.
+            # Shallow copy is safe as no nested data is present.
+            latest_room_serial = handler._latest_room_serial
+            room_serials = handler._room_serials.copy()
+
+            for room_id, serial in room_serials.items():
+                if serial <= from_key:
                     continue
 
                 if not await service.is_interested_in_room(room_id, self._main_store):
@@ -498,7 +503,7 @@ class TypingNotificationEventSource(EventSource[int, JsonDict]):
 
                 events.append(self._make_event_for(room_id))
 
-            return events, handler._latest_room_serial
+            return events, latest_room_serial
 
     async def get_new_events(
         self,
diff --git a/synapse/http/server.py b/synapse/http/server.py
index cf2d6f904b..19f42159b8 100644
--- a/synapse/http/server.py
+++ b/synapse/http/server.py
@@ -58,6 +58,7 @@ from synapse.api.errors import (
     SynapseError,
     UnrecognizedRequestError,
 )
+from synapse.config.homeserver import HomeServerConfig
 from synapse.http.site import SynapseRequest
 from synapse.logging.context import defer_to_thread, preserve_fn, run_in_background
 from synapse.logging.opentracing import active_span, start_active_span, trace_servlet
@@ -155,15 +156,16 @@ def is_method_cancellable(method: Callable[..., Any]) -> bool:
     return getattr(method, "cancellable", False)
 
 
-def return_json_error(f: failure.Failure, request: SynapseRequest) -> None:
+def return_json_error(
+    f: failure.Failure, request: SynapseRequest, config: Optional[HomeServerConfig]
+) -> None:
     """Sends a JSON error response to clients."""
 
     if f.check(SynapseError):
         # mypy doesn't understand that f.check asserts the type.
         exc: SynapseError = f.value  # type: ignore
         error_code = exc.code
-        error_dict = exc.error_dict()
-
+        error_dict = exc.error_dict(config)
         logger.info("%s SynapseError: %s - %s", request, error_code, exc.msg)
     elif f.check(CancelledError):
         error_code = HTTP_STATUS_REQUEST_CANCELLED
@@ -450,7 +452,7 @@ class DirectServeJsonResource(_AsyncResource):
         request: SynapseRequest,
     ) -> None:
         """Implements _AsyncResource._send_error_response"""
-        return_json_error(f, request)
+        return_json_error(f, request, None)
 
 
 @attr.s(slots=True, frozen=True, auto_attribs=True)
@@ -575,6 +577,14 @@ class JsonResource(DirectServeJsonResource):
 
         return callback_return
 
+    def _send_error_response(
+        self,
+        f: failure.Failure,
+        request: SynapseRequest,
+    ) -> None:
+        """Implements _AsyncResource._send_error_response"""
+        return_json_error(f, request, self.hs.config)
+
 
 class DirectServeHtmlResource(_AsyncResource):
     """A resource that will call `self._async_on_<METHOD>` on new requests,
diff --git a/synapse/http/servlet.py b/synapse/http/servlet.py
index 4ff840ca0e..26aaabfb34 100644
--- a/synapse/http/servlet.py
+++ b/synapse/http/servlet.py
@@ -23,9 +23,12 @@ from typing import (
     Optional,
     Sequence,
     Tuple,
+    Type,
+    TypeVar,
     overload,
 )
 
+from pydantic import BaseModel, ValidationError
 from typing_extensions import Literal
 
 from twisted.web.server import Request
@@ -694,6 +697,28 @@ def parse_json_object_from_request(
     return content
 
 
+Model = TypeVar("Model", bound=BaseModel)
+
+
+def parse_and_validate_json_object_from_request(
+    request: Request, model_type: Type[Model]
+) -> Model:
+    """Parse a JSON object from the body of a twisted HTTP request, then deserialise and
+    validate using the given pydantic model.
+
+    Raises:
+        SynapseError if the request body couldn't be decoded as JSON or
+            if it wasn't a JSON object.
+    """
+    content = parse_json_object_from_request(request, allow_empty_body=False)
+    try:
+        instance = model_type.parse_obj(content)
+    except ValidationError as e:
+        raise SynapseError(HTTPStatus.BAD_REQUEST, str(e), errcode=Codes.BAD_JSON)
+
+    return instance
+
+
 def assert_params_in_dict(body: JsonDict, required: Iterable[str]) -> None:
     absent = []
     for k in required:
diff --git a/synapse/http/site.py b/synapse/http/site.py
index eeec74b78a..1155f3f610 100644
--- a/synapse/http/site.py
+++ b/synapse/http/site.py
@@ -226,7 +226,7 @@ class SynapseRequest(Request):
 
             # If this is a request where the target user doesn't match the user who
             # authenticated (e.g. and admin is puppetting a user) then we return both.
-            if self._requester.user.to_string() != authenticated_entity:
+            if requester != authenticated_entity:
                 return requester, authenticated_entity
 
             return requester, None
diff --git a/synapse/logging/opentracing.py b/synapse/logging/opentracing.py
index 17e729f0c7..482316a1ff 100644
--- a/synapse/logging/opentracing.py
+++ b/synapse/logging/opentracing.py
@@ -173,6 +173,7 @@ from typing import (
     Any,
     Callable,
     Collection,
+    ContextManager,
     Dict,
     Generator,
     Iterable,
@@ -182,6 +183,8 @@ from typing import (
     Type,
     TypeVar,
     Union,
+    cast,
+    overload,
 )
 
 import attr
@@ -307,6 +310,19 @@ class SynapseTags:
     # The name of the external cache
     CACHE_NAME = "cache.name"
 
+    # Used to tag function arguments
+    #
+    # Tag a named arg. The name of the argument should be appended to this prefix.
+    FUNC_ARG_PREFIX = "ARG."
+    # Tag extra variadic number of positional arguments (`def foo(first, second, *extras)`)
+    FUNC_ARGS = "args"
+    # Tag keyword args
+    FUNC_KWARGS = "kwargs"
+
+    # Some intermediate result that's interesting to the function. The label for
+    # the result should be appended to this prefix.
+    RESULT_PREFIX = "RESULT."
+
 
 class SynapseBaggage:
     FORCE_TRACING = "synapse-force-tracing"
@@ -328,6 +344,7 @@ class _Sentinel(enum.Enum):
 
 P = ParamSpec("P")
 R = TypeVar("R")
+T = TypeVar("T")
 
 
 def only_if_tracing(func: Callable[P, R]) -> Callable[P, Optional[R]]:
@@ -343,22 +360,43 @@ def only_if_tracing(func: Callable[P, R]) -> Callable[P, Optional[R]]:
     return _only_if_tracing_inner
 
 
-def ensure_active_span(message: str, ret=None):
+@overload
+def ensure_active_span(
+    message: str,
+) -> Callable[[Callable[P, R]], Callable[P, Optional[R]]]:
+    ...
+
+
+@overload
+def ensure_active_span(
+    message: str, ret: T
+) -> Callable[[Callable[P, R]], Callable[P, Union[T, R]]]:
+    ...
+
+
+def ensure_active_span(
+    message: str, ret: Optional[T] = None
+) -> Callable[[Callable[P, R]], Callable[P, Union[Optional[T], R]]]:
     """Executes the operation only if opentracing is enabled and there is an active span.
     If there is no active span it logs message at the error level.
 
     Args:
         message: Message which fills in "There was no active span when trying to %s"
             in the error log if there is no active span and opentracing is enabled.
-        ret (object): return value if opentracing is None or there is no active span.
+        ret: return value if opentracing is None or there is no active span.
 
-    Returns (object): The result of the func or ret if opentracing is disabled or there
+    Returns:
+        The result of the func, falling back to ret if opentracing is disabled or there
         was no active span.
     """
 
-    def ensure_active_span_inner_1(func):
+    def ensure_active_span_inner_1(
+        func: Callable[P, R]
+    ) -> Callable[P, Union[Optional[T], R]]:
         @wraps(func)
-        def ensure_active_span_inner_2(*args, **kwargs):
+        def ensure_active_span_inner_2(
+            *args: P.args, **kwargs: P.kwargs
+        ) -> Union[Optional[T], R]:
             if not opentracing:
                 return ret
 
@@ -464,7 +502,7 @@ def start_active_span(
     finish_on_close: bool = True,
     *,
     tracer: Optional["opentracing.Tracer"] = None,
-):
+) -> "opentracing.Scope":
     """Starts an active opentracing span.
 
     Records the start time for the span, and sets it as the "active span" in the
@@ -502,7 +540,7 @@ def start_active_span_follows_from(
     *,
     inherit_force_tracing: bool = False,
     tracer: Optional["opentracing.Tracer"] = None,
-):
+) -> "opentracing.Scope":
     """Starts an active opentracing span, with additional references to previous spans
 
     Args:
@@ -717,7 +755,9 @@ def inject_response_headers(response_headers: Headers) -> None:
         response_headers.addRawHeader("Synapse-Trace-Id", f"{trace_id:x}")
 
 
-@ensure_active_span("get the active span context as a dict", ret={})
+@ensure_active_span(
+    "get the active span context as a dict", ret=cast(Dict[str, str], {})
+)
 def get_active_span_text_map(destination: Optional[str] = None) -> Dict[str, str]:
     """
     Gets a span context as a dict. This can be used instead of manually
@@ -797,75 +837,117 @@ def extract_text_map(carrier: Dict[str, str]) -> Optional["opentracing.SpanConte
 # Tracing decorators
 
 
-def trace_with_opname(opname: str) -> Callable[[Callable[P, R]], Callable[P, R]]:
+def _custom_sync_async_decorator(
+    func: Callable[P, R],
+    wrapping_logic: Callable[[Callable[P, R], Any, Any], ContextManager[None]],
+) -> Callable[P, R]:
     """
-    Decorator to trace a function with a custom opname.
-
-    See the module's doc string for usage examples.
+    Decorates a function that is sync or async (coroutines), or that returns a Twisted
+    `Deferred`. The custom business logic of the decorator goes in `wrapping_logic`.
+
+    Example usage:
+    ```py
+    # Decorator to time the function and log it out
+    def duration(func: Callable[P, R]) -> Callable[P, R]:
+        @contextlib.contextmanager
+        def _wrapping_logic(func: Callable[P, R], *args: P.args, **kwargs: P.kwargs) -> Generator[None, None, None]:
+            start_ts = time.time()
+            try:
+                yield
+            finally:
+                end_ts = time.time()
+                duration = end_ts - start_ts
+                logger.info("%s took %s seconds", func.__name__, duration)
+        return _custom_sync_async_decorator(func, _wrapping_logic)
+    ```
 
+    Args:
+        func: The function to be decorated
+        wrapping_logic: The business logic of your custom decorator.
+            This should be a ContextManager so you are able to run your logic
+            before/after the function as desired.
     """
 
-    def decorator(func: Callable[P, R]) -> Callable[P, R]:
-        if opentracing is None:
-            return func  # type: ignore[unreachable]
+    if inspect.iscoroutinefunction(func):
 
-        if inspect.iscoroutinefunction(func):
+        @wraps(func)
+        async def _wrapper(*args: P.args, **kwargs: P.kwargs) -> R:
+            with wrapping_logic(func, *args, **kwargs):
+                return await func(*args, **kwargs)  # type: ignore[misc]
 
-            @wraps(func)
-            async def _trace_inner(*args: P.args, **kwargs: P.kwargs) -> R:
-                with start_active_span(opname):
-                    return await func(*args, **kwargs)  # type: ignore[misc]
+    else:
+        # The other case here handles both sync functions and those
+        # decorated with inlineDeferred.
+        @wraps(func)
+        def _wrapper(*args: P.args, **kwargs: P.kwargs) -> R:
+            scope = wrapping_logic(func, *args, **kwargs)
+            scope.__enter__()
 
-        else:
-            # The other case here handles both sync functions and those
-            # decorated with inlineDeferred.
-            @wraps(func)
-            def _trace_inner(*args: P.args, **kwargs: P.kwargs) -> R:
-                scope = start_active_span(opname)
-                scope.__enter__()
-
-                try:
-                    result = func(*args, **kwargs)
-                    if isinstance(result, defer.Deferred):
-
-                        def call_back(result: R) -> R:
-                            scope.__exit__(None, None, None)
-                            return result
-
-                        def err_back(result: R) -> R:
-                            scope.__exit__(None, None, None)
-                            return result
-
-                        result.addCallbacks(call_back, err_back)
-
-                    else:
-                        if inspect.isawaitable(result):
-                            logger.error(
-                                "@trace may not have wrapped %s correctly! "
-                                "The function is not async but returned a %s.",
-                                func.__qualname__,
-                                type(result).__name__,
-                            )
+            try:
+                result = func(*args, **kwargs)
+                if isinstance(result, defer.Deferred):
+
+                    def call_back(result: R) -> R:
+                        scope.__exit__(None, None, None)
+                        return result
 
+                    def err_back(result: R) -> R:
                         scope.__exit__(None, None, None)
+                        return result
+
+                    result.addCallbacks(call_back, err_back)
+
+                else:
+                    if inspect.isawaitable(result):
+                        logger.error(
+                            "@trace may not have wrapped %s correctly! "
+                            "The function is not async but returned a %s.",
+                            func.__qualname__,
+                            type(result).__name__,
+                        )
+
+                    scope.__exit__(None, None, None)
+
+                return result
+
+            except Exception as e:
+                scope.__exit__(type(e), None, e.__traceback__)
+                raise
+
+    return _wrapper  # type: ignore[return-value]
+
+
+def trace_with_opname(
+    opname: str,
+    *,
+    tracer: Optional["opentracing.Tracer"] = None,
+) -> Callable[[Callable[P, R]], Callable[P, R]]:
+    """
+    Decorator to trace a function with a custom opname.
+    See the module's doc string for usage examples.
+    """
 
-                    return result
+    # type-ignore: mypy bug, see https://github.com/python/mypy/issues/12909
+    @contextlib.contextmanager  # type: ignore[arg-type]
+    def _wrapping_logic(
+        func: Callable[P, R], *args: P.args, **kwargs: P.kwargs
+    ) -> Generator[None, None, None]:
+        with start_active_span(opname, tracer=tracer):
+            yield
 
-                except Exception as e:
-                    scope.__exit__(type(e), None, e.__traceback__)
-                    raise
+    def _decorator(func: Callable[P, R]) -> Callable[P, R]:
+        if not opentracing:
+            return func
 
-        return _trace_inner  # type: ignore[return-value]
+        return _custom_sync_async_decorator(func, _wrapping_logic)
 
-    return decorator
+    return _decorator
 
 
 def trace(func: Callable[P, R]) -> Callable[P, R]:
     """
     Decorator to trace a function.
-
     Sets the operation name to that of the function's name.
-
     See the module's doc string for usage examples.
     """
 
@@ -874,22 +956,36 @@ def trace(func: Callable[P, R]) -> Callable[P, R]:
 
 def tag_args(func: Callable[P, R]) -> Callable[P, R]:
     """
-    Tags all of the args to the active span.
+    Decorator to tag all of the args to the active span.
+
+    Args:
+        func: `func` is assumed to be a method taking a `self` parameter, or a
+            `classmethod` taking a `cls` parameter. In either case, a tag is not
+            created for this parameter.
     """
 
     if not opentracing:
         return func
 
-    @wraps(func)
-    def _tag_args_inner(*args: P.args, **kwargs: P.kwargs) -> R:
+    # type-ignore: mypy bug, see https://github.com/python/mypy/issues/12909
+    @contextlib.contextmanager  # type: ignore[arg-type]
+    def _wrapping_logic(
+        func: Callable[P, R], *args: P.args, **kwargs: P.kwargs
+    ) -> Generator[None, None, None]:
         argspec = inspect.getfullargspec(func)
-        for i, arg in enumerate(argspec.args[1:]):
-            set_tag("ARG_" + arg, args[i])  # type: ignore[index]
-        set_tag("args", args[len(argspec.args) :])  # type: ignore[index]
-        set_tag("kwargs", kwargs)
-        return func(*args, **kwargs)
-
-    return _tag_args_inner
+        # We use `[1:]` to skip the `self` object reference and `start=1` to
+        # make the index line up with `argspec.args`.
+        #
+        # FIXME: We could update this to handle any type of function by ignoring the
+        #   first argument only if it's named `self` or `cls`. This isn't fool-proof
+        #   but handles the idiomatic cases.
+        for i, arg in enumerate(args[1:], start=1):  # type: ignore[index]
+            set_tag(SynapseTags.FUNC_ARG_PREFIX + argspec.args[i], str(arg))
+        set_tag(SynapseTags.FUNC_ARGS, str(args[len(argspec.args) :]))  # type: ignore[index]
+        set_tag(SynapseTags.FUNC_KWARGS, str(kwargs))
+        yield
+
+    return _custom_sync_async_decorator(func, _wrapping_logic)
 
 
 @contextlib.contextmanager
diff --git a/synapse/metrics/background_process_metrics.py b/synapse/metrics/background_process_metrics.py
index eef3462e10..7a1516d3a8 100644
--- a/synapse/metrics/background_process_metrics.py
+++ b/synapse/metrics/background_process_metrics.py
@@ -235,7 +235,7 @@ def run_as_background_process(
                         f"bgproc.{desc}", tags={SynapseTags.REQUEST_ID: str(context)}
                     )
                 else:
-                    ctx = nullcontext()
+                    ctx = nullcontext()  # type: ignore[assignment]
                 with ctx:
                     return await func(*args, **kwargs)
             except Exception:
diff --git a/synapse/module_api/__init__.py b/synapse/module_api/__init__.py
index 6d8bf54083..87ba154cb7 100644
--- a/synapse/module_api/__init__.py
+++ b/synapse/module_api/__init__.py
@@ -929,10 +929,12 @@ class ModuleApi:
         room_id: str,
         new_membership: str,
         content: Optional[JsonDict] = None,
+        remote_room_hosts: Optional[List[str]] = None,
     ) -> EventBase:
         """Updates the membership of a user to the given value.
 
         Added in Synapse v1.46.0.
+        Changed in Synapse v1.65.0: Added the 'remote_room_hosts' parameter.
 
         Args:
             sender: The user performing the membership change. Must be a user local to
@@ -946,6 +948,7 @@ class ModuleApi:
                 https://spec.matrix.org/unstable/client-server-api/#mroommember for the
                 list of allowed values.
             content: Additional values to include in the resulting event's content.
+            remote_room_hosts: Remote servers to use for remote joins/knocks/etc.
 
         Returns:
             The newly created membership event.
@@ -1005,15 +1008,12 @@ class ModuleApi:
             room_id=room_id,
             action=new_membership,
             content=content,
+            remote_room_hosts=remote_room_hosts,
         )
 
         # Try to retrieve the resulting event.
         event = await self._hs.get_datastores().main.get_event(event_id)
 
-        # update_membership is supposed to always return after the event has been
-        # successfully persisted.
-        assert event is not None
-
         return event
 
     async def create_and_send_event_into_room(self, event_dict: JsonDict) -> EventBase:
@@ -1452,6 +1452,81 @@ class ModuleApi:
             start_timestamp, end_timestamp
         )
 
+    async def lookup_room_alias(self, room_alias: str) -> Tuple[str, List[str]]:
+        """
+        Get the room ID associated with a room alias.
+
+        Added in Synapse v1.65.0.
+
+        Args:
+            room_alias: The alias to look up.
+
+        Returns:
+            A tuple of:
+                The room ID (str).
+                Hosts likely to be participating in the room ([str]).
+
+        Raises:
+            SynapseError if room alias is invalid or could not be found.
+        """
+        alias = RoomAlias.from_string(room_alias)
+        (room_id, hosts) = await self._hs.get_room_member_handler().lookup_room_alias(
+            alias
+        )
+
+        return room_id.to_string(), hosts
+
+    async def create_room(
+        self,
+        user_id: str,
+        config: JsonDict,
+        ratelimit: bool = True,
+        creator_join_profile: Optional[JsonDict] = None,
+    ) -> Tuple[str, Optional[str]]:
+        """Creates a new room.
+
+        Added in Synapse v1.65.0.
+
+        Args:
+            user_id:
+                The user who requested the room creation.
+            config : A dict of configuration options. See "Request body" of:
+                https://spec.matrix.org/latest/client-server-api/#post_matrixclientv3createroom
+            ratelimit: set to False to disable the rate limiter for this specific operation.
+
+            creator_join_profile:
+                Set to override the displayname and avatar for the creating
+                user in this room. If unset, displayname and avatar will be
+                derived from the user's profile. If set, should contain the
+                values to go in the body of the 'join' event (typically
+                `avatar_url` and/or `displayname`.
+
+        Returns:
+                A tuple containing: 1) the room ID (str), 2) if an alias was requested,
+                the room alias (str), otherwise None if no alias was requested.
+
+        Raises:
+            ResourceLimitError if server is blocked to some resource being
+            exceeded.
+            RuntimeError if the user_id does not refer to a local user.
+            SynapseError if the user_id is invalid, room ID couldn't be stored, or
+            something went horribly wrong.
+        """
+        if not self.is_mine(user_id):
+            raise RuntimeError(
+                "Tried to create a room as a user that isn't local to this homeserver",
+            )
+
+        requester = create_requester(user_id)
+        room_id_and_alias, _ = await self._hs.get_room_creation_handler().create_room(
+            requester=requester,
+            config=config,
+            ratelimit=ratelimit,
+            creator_join_profile=creator_join_profile,
+        )
+
+        return room_id_and_alias["room_id"], room_id_and_alias.get("room_alias", None)
+
 
 class PublicRoomListManager:
     """Contains methods for adding to, removing from and querying whether a room
diff --git a/synapse/push/baserules.py b/synapse/push/baserules.py
index 6c0cc5a6ce..440205e80c 100644
--- a/synapse/push/baserules.py
+++ b/synapse/push/baserules.py
@@ -14,128 +14,235 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import copy
-from typing import Any, Dict, List
-
-from synapse.push.rulekinds import PRIORITY_CLASS_INVERSE_MAP, PRIORITY_CLASS_MAP
+"""
+Push rules is the system used to determine which events trigger a push (and a
+bump in notification counts).
+
+This consists of a list of "push rules" for each user, where a push rule is a
+pair of "conditions" and "actions". When a user receives an event Synapse
+iterates over the list of push rules until it finds one where all the conditions
+match the event, at which point "actions" describe the outcome (e.g. notify,
+highlight, etc).
+
+Push rules are split up into 5 different "kinds" (aka "priority classes"), which
+are run in order:
+    1. Override — highest priority rules, e.g. always ignore notices
+    2. Content — content specific rules, e.g. @ notifications
+    3. Room — per room rules, e.g. enable/disable notifications for all messages
+       in a room
+    4. Sender — per sender rules, e.g. never notify for messages from a given
+       user
+    5. Underride — the lowest priority "default" rules, e.g. notify for every
+       message.
+
+The set of "base rules" are the list of rules that every user has by default. A
+user can modify their copy of the push rules in one of three ways:
+
+    1. Adding a new push rule of a certain kind
+    2. Changing the actions of a base rule
+    3. Enabling/disabling a base rule.
+
+The base rules are split into whether they come before or after a particular
+kind, so the order of push rule evaluation would be: base rules for before
+"override" kind, user defined "override" rules, base rules after "override"
+kind, etc, etc.
+"""
+
+import itertools
+import logging
+from typing import Dict, Iterator, List, Mapping, Sequence, Tuple, Union
+
+import attr
+
+from synapse.config.experimental import ExperimentalConfig
+from synapse.push.rulekinds import PRIORITY_CLASS_MAP
+
+logger = logging.getLogger(__name__)
+
+
+@attr.s(auto_attribs=True, slots=True, frozen=True)
+class PushRule:
+    """A push rule
+
+    Attributes:
+        rule_id: a unique ID for this rule
+        priority_class: what "kind" of push rule this is (see
+            `PRIORITY_CLASS_MAP` for mapping between int and kind)
+        conditions: the sequence of conditions that all need to match
+        actions: the actions to apply if all conditions are met
+        default: is this a base rule?
+        default_enabled: is this enabled by default?
+    """
 
+    rule_id: str
+    priority_class: int
+    conditions: Sequence[Mapping[str, str]]
+    actions: Sequence[Union[str, Mapping]]
+    default: bool = False
+    default_enabled: bool = True
 
-def list_with_base_rules(rawrules: List[Dict[str, Any]]) -> List[Dict[str, Any]]:
-    """Combine the list of rules set by the user with the default push rules
 
-    Args:
-        rawrules: The rules the user has modified or set.
+@attr.s(auto_attribs=True, slots=True, frozen=True, weakref_slot=False)
+class PushRules:
+    """A collection of push rules for an account.
 
-    Returns:
-        A new list with the rules set by the user combined with the defaults.
+    Can be iterated over, producing push rules in priority order.
     """
-    ruleslist = []
 
-    # Grab the base rules that the user has modified.
-    # The modified base rules have a priority_class of -1.
-    modified_base_rules = {r["rule_id"]: r for r in rawrules if r["priority_class"] < 0}
+    # A mapping from rule ID to push rule that overrides a base rule. These will
+    # be returned instead of the base rule.
+    overriden_base_rules: Dict[str, PushRule] = attr.Factory(dict)
+
+    # The following stores the custom push rules at each priority class.
+    #
+    # We keep these separate (rather than combining into one big list) to avoid
+    # copying the base rules around all the time.
+    override: List[PushRule] = attr.Factory(list)
+    content: List[PushRule] = attr.Factory(list)
+    room: List[PushRule] = attr.Factory(list)
+    sender: List[PushRule] = attr.Factory(list)
+    underride: List[PushRule] = attr.Factory(list)
+
+    def __iter__(self) -> Iterator[PushRule]:
+        # When iterating over the push rules we need to return the base rules
+        # interspersed at the correct spots.
+        for rule in itertools.chain(
+            BASE_PREPEND_OVERRIDE_RULES,
+            self.override,
+            BASE_APPEND_OVERRIDE_RULES,
+            self.content,
+            BASE_APPEND_CONTENT_RULES,
+            self.room,
+            self.sender,
+            self.underride,
+            BASE_APPEND_UNDERRIDE_RULES,
+        ):
+            # Check if a base rule has been overriden by a custom rule. If so
+            # return that instead.
+            override_rule = self.overriden_base_rules.get(rule.rule_id)
+            if override_rule:
+                yield override_rule
+            else:
+                yield rule
+
+    def __len__(self) -> int:
+        # The length is mostly used by caches to get a sense of "size" / amount
+        # of memory this object is using, so we only count the number of custom
+        # rules.
+        return (
+            len(self.overriden_base_rules)
+            + len(self.override)
+            + len(self.content)
+            + len(self.room)
+            + len(self.sender)
+            + len(self.underride)
+        )
 
-    # Remove the modified base rules from the list, They'll be added back
-    # in the default positions in the list.
-    rawrules = [r for r in rawrules if r["priority_class"] >= 0]
 
-    # shove the server default rules for each kind onto the end of each
-    current_prio_class = list(PRIORITY_CLASS_INVERSE_MAP)[-1]
+@attr.s(auto_attribs=True, slots=True, frozen=True, weakref_slot=False)
+class FilteredPushRules:
+    """A wrapper around `PushRules` that filters out disabled experimental push
+    rules, and includes the "enabled" state for each rule when iterated over.
+    """
 
-    ruleslist.extend(
-        make_base_prepend_rules(
-            PRIORITY_CLASS_INVERSE_MAP[current_prio_class], modified_base_rules
-        )
-    )
+    push_rules: PushRules
+    enabled_map: Dict[str, bool]
+    experimental_config: ExperimentalConfig
 
-    for r in rawrules:
-        if r["priority_class"] < current_prio_class:
-            while r["priority_class"] < current_prio_class:
-                ruleslist.extend(
-                    make_base_append_rules(
-                        PRIORITY_CLASS_INVERSE_MAP[current_prio_class],
-                        modified_base_rules,
-                    )
-                )
-                current_prio_class -= 1
-                if current_prio_class > 0:
-                    ruleslist.extend(
-                        make_base_prepend_rules(
-                            PRIORITY_CLASS_INVERSE_MAP[current_prio_class],
-                            modified_base_rules,
-                        )
-                    )
-
-        ruleslist.append(r)
-
-    while current_prio_class > 0:
-        ruleslist.extend(
-            make_base_append_rules(
-                PRIORITY_CLASS_INVERSE_MAP[current_prio_class], modified_base_rules
-            )
-        )
-        current_prio_class -= 1
-        if current_prio_class > 0:
-            ruleslist.extend(
-                make_base_prepend_rules(
-                    PRIORITY_CLASS_INVERSE_MAP[current_prio_class], modified_base_rules
-                )
-            )
+    def __iter__(self) -> Iterator[Tuple[PushRule, bool]]:
+        for rule in self.push_rules:
+            if not _is_experimental_rule_enabled(
+                rule.rule_id, self.experimental_config
+            ):
+                continue
 
-    return ruleslist
+            enabled = self.enabled_map.get(rule.rule_id, rule.default_enabled)
 
+            yield rule, enabled
 
-def make_base_append_rules(
-    kind: str, modified_base_rules: Dict[str, Dict[str, Any]]
-) -> List[Dict[str, Any]]:
-    rules = []
+    def __len__(self) -> int:
+        return len(self.push_rules)
 
-    if kind == "override":
-        rules = BASE_APPEND_OVERRIDE_RULES
-    elif kind == "underride":
-        rules = BASE_APPEND_UNDERRIDE_RULES
-    elif kind == "content":
-        rules = BASE_APPEND_CONTENT_RULES
 
-    # Copy the rules before modifying them
-    rules = copy.deepcopy(rules)
-    for r in rules:
-        # Only modify the actions, keep the conditions the same.
-        assert isinstance(r["rule_id"], str)
-        modified = modified_base_rules.get(r["rule_id"])
-        if modified:
-            r["actions"] = modified["actions"]
+DEFAULT_EMPTY_PUSH_RULES = PushRules()
 
-    return rules
 
+def compile_push_rules(rawrules: List[PushRule]) -> PushRules:
+    """Given a set of custom push rules return a `PushRules` instance (which
+    includes the base rules).
+    """
+
+    if not rawrules:
+        # Fast path to avoid allocating empty lists when there are no custom
+        # rules for the user.
+        return DEFAULT_EMPTY_PUSH_RULES
+
+    rules = PushRules()
 
-def make_base_prepend_rules(
-    kind: str,
-    modified_base_rules: Dict[str, Dict[str, Any]],
-) -> List[Dict[str, Any]]:
-    rules = []
+    for rule in rawrules:
+        # We need to decide which bucket each custom push rule goes into.
 
-    if kind == "override":
-        rules = BASE_PREPEND_OVERRIDE_RULES
+        # If it has the same ID as a base rule then it overrides that...
+        overriden_base_rule = BASE_RULES_BY_ID.get(rule.rule_id)
+        if overriden_base_rule:
+            rules.overriden_base_rules[rule.rule_id] = attr.evolve(
+                overriden_base_rule, actions=rule.actions
+            )
+            continue
+
+        # ... otherwise it gets added to the appropriate priority class bucket
+        collection: List[PushRule]
+        if rule.priority_class == 5:
+            collection = rules.override
+        elif rule.priority_class == 4:
+            collection = rules.content
+        elif rule.priority_class == 3:
+            collection = rules.room
+        elif rule.priority_class == 2:
+            collection = rules.sender
+        elif rule.priority_class == 1:
+            collection = rules.underride
+        elif rule.priority_class <= 0:
+            logger.info(
+                "Got rule with priority class less than zero, but doesn't override a base rule: %s",
+                rule,
+            )
+            continue
+        else:
+            # We log and continue here so as not to break event sending
+            logger.error("Unknown priority class: %", rule.priority_class)
+            continue
 
-    # Copy the rules before modifying them
-    rules = copy.deepcopy(rules)
-    for r in rules:
-        # Only modify the actions, keep the conditions the same.
-        assert isinstance(r["rule_id"], str)
-        modified = modified_base_rules.get(r["rule_id"])
-        if modified:
-            r["actions"] = modified["actions"]
+        collection.append(rule)
 
     return rules
 
 
-# We have to annotate these types, otherwise mypy infers them as
-# `List[Dict[str, Sequence[Collection[str]]]]`.
-BASE_APPEND_CONTENT_RULES: List[Dict[str, Any]] = [
-    {
-        "rule_id": "global/content/.m.rule.contains_user_name",
-        "conditions": [
+def _is_experimental_rule_enabled(
+    rule_id: str, experimental_config: ExperimentalConfig
+) -> bool:
+    """Used by `FilteredPushRules` to filter out experimental rules when they
+    have not been enabled.
+    """
+    if (
+        rule_id == "global/override/.org.matrix.msc3786.rule.room.server_acl"
+        and not experimental_config.msc3786_enabled
+    ):
+        return False
+    if (
+        rule_id == "global/underride/.org.matrix.msc3772.thread_reply"
+        and not experimental_config.msc3772_enabled
+    ):
+        return False
+    return True
+
+
+BASE_APPEND_CONTENT_RULES = [
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["content"],
+        rule_id="global/content/.m.rule.contains_user_name",
+        conditions=[
             {
                 "kind": "event_match",
                 "key": "content.body",
@@ -143,29 +250,33 @@ BASE_APPEND_CONTENT_RULES: List[Dict[str, Any]] = [
                 "pattern_type": "user_localpart",
             }
         ],
-        "actions": [
+        actions=[
             "notify",
             {"set_tweak": "sound", "value": "default"},
             {"set_tweak": "highlight"},
         ],
-    }
+    )
 ]
 
 
-BASE_PREPEND_OVERRIDE_RULES: List[Dict[str, Any]] = [
-    {
-        "rule_id": "global/override/.m.rule.master",
-        "enabled": False,
-        "conditions": [],
-        "actions": ["dont_notify"],
-    }
+BASE_PREPEND_OVERRIDE_RULES = [
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["override"],
+        rule_id="global/override/.m.rule.master",
+        default_enabled=False,
+        conditions=[],
+        actions=["dont_notify"],
+    )
 ]
 
 
-BASE_APPEND_OVERRIDE_RULES: List[Dict[str, Any]] = [
-    {
-        "rule_id": "global/override/.m.rule.suppress_notices",
-        "conditions": [
+BASE_APPEND_OVERRIDE_RULES = [
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["override"],
+        rule_id="global/override/.m.rule.suppress_notices",
+        conditions=[
             {
                 "kind": "event_match",
                 "key": "content.msgtype",
@@ -173,13 +284,15 @@ BASE_APPEND_OVERRIDE_RULES: List[Dict[str, Any]] = [
                 "_cache_key": "_suppress_notices",
             }
         ],
-        "actions": ["dont_notify"],
-    },
+        actions=["dont_notify"],
+    ),
     # NB. .m.rule.invite_for_me must be higher prio than .m.rule.member_event
     # otherwise invites will be matched by .m.rule.member_event
-    {
-        "rule_id": "global/override/.m.rule.invite_for_me",
-        "conditions": [
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["override"],
+        rule_id="global/override/.m.rule.invite_for_me",
+        conditions=[
             {
                 "kind": "event_match",
                 "key": "type",
@@ -195,21 +308,23 @@ BASE_APPEND_OVERRIDE_RULES: List[Dict[str, Any]] = [
             # Match the requester's MXID.
             {"kind": "event_match", "key": "state_key", "pattern_type": "user_id"},
         ],
-        "actions": [
+        actions=[
             "notify",
             {"set_tweak": "sound", "value": "default"},
             {"set_tweak": "highlight", "value": False},
         ],
-    },
+    ),
     # Will we sometimes want to know about people joining and leaving?
     # Perhaps: if so, this could be expanded upon. Seems the most usual case
     # is that we don't though. We add this override rule so that even if
     # the room rule is set to notify, we don't get notifications about
     # join/leave/avatar/displayname events.
     # See also: https://matrix.org/jira/browse/SYN-607
-    {
-        "rule_id": "global/override/.m.rule.member_event",
-        "conditions": [
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["override"],
+        rule_id="global/override/.m.rule.member_event",
+        conditions=[
             {
                 "kind": "event_match",
                 "key": "type",
@@ -217,24 +332,28 @@ BASE_APPEND_OVERRIDE_RULES: List[Dict[str, Any]] = [
                 "_cache_key": "_member",
             }
         ],
-        "actions": ["dont_notify"],
-    },
+        actions=["dont_notify"],
+    ),
     # This was changed from underride to override so it's closer in priority
     # to the content rules where the user name highlight rule lives. This
     # way a room rule is lower priority than both but a custom override rule
     # is higher priority than both.
-    {
-        "rule_id": "global/override/.m.rule.contains_display_name",
-        "conditions": [{"kind": "contains_display_name"}],
-        "actions": [
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["override"],
+        rule_id="global/override/.m.rule.contains_display_name",
+        conditions=[{"kind": "contains_display_name"}],
+        actions=[
             "notify",
             {"set_tweak": "sound", "value": "default"},
             {"set_tweak": "highlight"},
         ],
-    },
-    {
-        "rule_id": "global/override/.m.rule.roomnotif",
-        "conditions": [
+    ),
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["override"],
+        rule_id="global/override/.m.rule.roomnotif",
+        conditions=[
             {
                 "kind": "event_match",
                 "key": "content.body",
@@ -247,11 +366,13 @@ BASE_APPEND_OVERRIDE_RULES: List[Dict[str, Any]] = [
                 "_cache_key": "_roomnotif_pl",
             },
         ],
-        "actions": ["notify", {"set_tweak": "highlight", "value": True}],
-    },
-    {
-        "rule_id": "global/override/.m.rule.tombstone",
-        "conditions": [
+        actions=["notify", {"set_tweak": "highlight", "value": True}],
+    ),
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["override"],
+        rule_id="global/override/.m.rule.tombstone",
+        conditions=[
             {
                 "kind": "event_match",
                 "key": "type",
@@ -265,11 +386,13 @@ BASE_APPEND_OVERRIDE_RULES: List[Dict[str, Any]] = [
                 "_cache_key": "_tombstone_statekey",
             },
         ],
-        "actions": ["notify", {"set_tweak": "highlight", "value": True}],
-    },
-    {
-        "rule_id": "global/override/.m.rule.reaction",
-        "conditions": [
+        actions=["notify", {"set_tweak": "highlight", "value": True}],
+    ),
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["override"],
+        rule_id="global/override/.m.rule.reaction",
+        conditions=[
             {
                 "kind": "event_match",
                 "key": "type",
@@ -277,14 +400,16 @@ BASE_APPEND_OVERRIDE_RULES: List[Dict[str, Any]] = [
                 "_cache_key": "_reaction",
             }
         ],
-        "actions": ["dont_notify"],
-    },
+        actions=["dont_notify"],
+    ),
     # XXX: This is an experimental rule that is only enabled if msc3786_enabled
     # is enabled, if it is not the rule gets filtered out in _load_rules() in
     # PushRulesWorkerStore
-    {
-        "rule_id": "global/override/.org.matrix.msc3786.rule.room.server_acl",
-        "conditions": [
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["override"],
+        rule_id="global/override/.org.matrix.msc3786.rule.room.server_acl",
+        conditions=[
             {
                 "kind": "event_match",
                 "key": "type",
@@ -298,15 +423,17 @@ BASE_APPEND_OVERRIDE_RULES: List[Dict[str, Any]] = [
                 "_cache_key": "_room_server_acl_state_key",
             },
         ],
-        "actions": [],
-    },
+        actions=[],
+    ),
 ]
 
 
-BASE_APPEND_UNDERRIDE_RULES: List[Dict[str, Any]] = [
-    {
-        "rule_id": "global/underride/.m.rule.call",
-        "conditions": [
+BASE_APPEND_UNDERRIDE_RULES = [
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["underride"],
+        rule_id="global/underride/.m.rule.call",
+        conditions=[
             {
                 "kind": "event_match",
                 "key": "type",
@@ -314,17 +441,19 @@ BASE_APPEND_UNDERRIDE_RULES: List[Dict[str, Any]] = [
                 "_cache_key": "_call",
             }
         ],
-        "actions": [
+        actions=[
             "notify",
             {"set_tweak": "sound", "value": "ring"},
             {"set_tweak": "highlight", "value": False},
         ],
-    },
+    ),
     # XXX: once m.direct is standardised everywhere, we should use it to detect
     # a DM from the user's perspective rather than this heuristic.
-    {
-        "rule_id": "global/underride/.m.rule.room_one_to_one",
-        "conditions": [
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["underride"],
+        rule_id="global/underride/.m.rule.room_one_to_one",
+        conditions=[
             {"kind": "room_member_count", "is": "2", "_cache_key": "member_count"},
             {
                 "kind": "event_match",
@@ -333,17 +462,19 @@ BASE_APPEND_UNDERRIDE_RULES: List[Dict[str, Any]] = [
                 "_cache_key": "_message",
             },
         ],
-        "actions": [
+        actions=[
             "notify",
             {"set_tweak": "sound", "value": "default"},
             {"set_tweak": "highlight", "value": False},
         ],
-    },
+    ),
     # XXX: this is going to fire for events which aren't m.room.messages
     # but are encrypted (e.g. m.call.*)...
-    {
-        "rule_id": "global/underride/.m.rule.encrypted_room_one_to_one",
-        "conditions": [
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["underride"],
+        rule_id="global/underride/.m.rule.encrypted_room_one_to_one",
+        conditions=[
             {"kind": "room_member_count", "is": "2", "_cache_key": "member_count"},
             {
                 "kind": "event_match",
@@ -352,15 +483,17 @@ BASE_APPEND_UNDERRIDE_RULES: List[Dict[str, Any]] = [
                 "_cache_key": "_encrypted",
             },
         ],
-        "actions": [
+        actions=[
             "notify",
             {"set_tweak": "sound", "value": "default"},
             {"set_tweak": "highlight", "value": False},
         ],
-    },
-    {
-        "rule_id": "global/underride/.org.matrix.msc3772.thread_reply",
-        "conditions": [
+    ),
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["underride"],
+        rule_id="global/underride/.org.matrix.msc3772.thread_reply",
+        conditions=[
             {
                 "kind": "org.matrix.msc3772.relation_match",
                 "rel_type": "m.thread",
@@ -368,11 +501,13 @@ BASE_APPEND_UNDERRIDE_RULES: List[Dict[str, Any]] = [
                 "sender_type": "user_id",
             }
         ],
-        "actions": ["notify", {"set_tweak": "highlight", "value": False}],
-    },
-    {
-        "rule_id": "global/underride/.m.rule.message",
-        "conditions": [
+        actions=["notify", {"set_tweak": "highlight", "value": False}],
+    ),
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["underride"],
+        rule_id="global/underride/.m.rule.message",
+        conditions=[
             {
                 "kind": "event_match",
                 "key": "type",
@@ -380,13 +515,15 @@ BASE_APPEND_UNDERRIDE_RULES: List[Dict[str, Any]] = [
                 "_cache_key": "_message",
             }
         ],
-        "actions": ["notify", {"set_tweak": "highlight", "value": False}],
-    },
+        actions=["notify", {"set_tweak": "highlight", "value": False}],
+    ),
     # XXX: this is going to fire for events which aren't m.room.messages
     # but are encrypted (e.g. m.call.*)...
-    {
-        "rule_id": "global/underride/.m.rule.encrypted",
-        "conditions": [
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["underride"],
+        rule_id="global/underride/.m.rule.encrypted",
+        conditions=[
             {
                 "kind": "event_match",
                 "key": "type",
@@ -394,11 +531,13 @@ BASE_APPEND_UNDERRIDE_RULES: List[Dict[str, Any]] = [
                 "_cache_key": "_encrypted",
             }
         ],
-        "actions": ["notify", {"set_tweak": "highlight", "value": False}],
-    },
-    {
-        "rule_id": "global/underride/.im.vector.jitsi",
-        "conditions": [
+        actions=["notify", {"set_tweak": "highlight", "value": False}],
+    ),
+    PushRule(
+        default=True,
+        priority_class=PRIORITY_CLASS_MAP["underride"],
+        rule_id="global/underride/.im.vector.jitsi",
+        conditions=[
             {
                 "kind": "event_match",
                 "key": "type",
@@ -418,29 +557,27 @@ BASE_APPEND_UNDERRIDE_RULES: List[Dict[str, Any]] = [
                 "_cache_key": "_is_state_event",
             },
         ],
-        "actions": ["notify", {"set_tweak": "highlight", "value": False}],
-    },
+        actions=["notify", {"set_tweak": "highlight", "value": False}],
+    ),
 ]
 
 
 BASE_RULE_IDS = set()
 
+BASE_RULES_BY_ID: Dict[str, PushRule] = {}
+
 for r in BASE_APPEND_CONTENT_RULES:
-    r["priority_class"] = PRIORITY_CLASS_MAP["content"]
-    r["default"] = True
-    BASE_RULE_IDS.add(r["rule_id"])
+    BASE_RULE_IDS.add(r.rule_id)
+    BASE_RULES_BY_ID[r.rule_id] = r
 
 for r in BASE_PREPEND_OVERRIDE_RULES:
-    r["priority_class"] = PRIORITY_CLASS_MAP["override"]
-    r["default"] = True
-    BASE_RULE_IDS.add(r["rule_id"])
+    BASE_RULE_IDS.add(r.rule_id)
+    BASE_RULES_BY_ID[r.rule_id] = r
 
 for r in BASE_APPEND_OVERRIDE_RULES:
-    r["priority_class"] = PRIORITY_CLASS_MAP["override"]
-    r["default"] = True
-    BASE_RULE_IDS.add(r["rule_id"])
+    BASE_RULE_IDS.add(r.rule_id)
+    BASE_RULES_BY_ID[r.rule_id] = r
 
 for r in BASE_APPEND_UNDERRIDE_RULES:
-    r["priority_class"] = PRIORITY_CLASS_MAP["underride"]
-    r["default"] = True
-    BASE_RULE_IDS.add(r["rule_id"])
+    BASE_RULE_IDS.add(r.rule_id)
+    BASE_RULES_BY_ID[r.rule_id] = r
diff --git a/synapse/push/bulk_push_rule_evaluator.py b/synapse/push/bulk_push_rule_evaluator.py
index 713dcf6950..ccd512be54 100644
--- a/synapse/push/bulk_push_rule_evaluator.py
+++ b/synapse/push/bulk_push_rule_evaluator.py
@@ -15,7 +15,18 @@
 
 import itertools
 import logging
-from typing import TYPE_CHECKING, Any, Dict, Iterable, List, Optional, Set, Tuple, Union
+from typing import (
+    TYPE_CHECKING,
+    Collection,
+    Dict,
+    Iterable,
+    List,
+    Mapping,
+    Optional,
+    Set,
+    Tuple,
+    Union,
+)
 
 from prometheus_client import Counter
 
@@ -30,6 +41,7 @@ from synapse.util.caches import register_cache
 from synapse.util.metrics import measure_func
 from synapse.visibility import filter_event_for_clients_with_state
 
+from .baserules import FilteredPushRules, PushRule
 from .push_rule_evaluator import PushRuleEvaluatorForEvent
 
 if TYPE_CHECKING:
@@ -112,7 +124,7 @@ class BulkPushRuleEvaluator:
     async def _get_rules_for_event(
         self,
         event: EventBase,
-    ) -> Dict[str, List[Dict[str, Any]]]:
+    ) -> Dict[str, FilteredPushRules]:
         """Get the push rules for all users who may need to be notified about
         the event.
 
@@ -186,7 +198,7 @@ class BulkPushRuleEvaluator:
         return pl_event.content if pl_event else {}, sender_level
 
     async def _get_mutual_relations(
-        self, event: EventBase, rules: Iterable[Dict[str, Any]]
+        self, event: EventBase, rules: Iterable[Tuple[PushRule, bool]]
     ) -> Dict[str, Set[Tuple[str, str]]]:
         """
         Fetch event metadata for events which related to the same event as the given event.
@@ -216,12 +228,11 @@ class BulkPushRuleEvaluator:
 
         # Pre-filter to figure out which relation types are interesting.
         rel_types = set()
-        for rule in rules:
-            # Skip disabled rules.
-            if "enabled" in rule and not rule["enabled"]:
+        for rule, enabled in rules:
+            if not enabled:
                 continue
 
-            for condition in rule["conditions"]:
+            for condition in rule.conditions:
                 if condition["kind"] != "org.matrix.msc3772.relation_match":
                     continue
 
@@ -254,7 +265,7 @@ class BulkPushRuleEvaluator:
         count_as_unread = _should_count_as_unread(event, context)
 
         rules_by_user = await self._get_rules_for_event(event)
-        actions_by_user: Dict[str, List[Union[dict, str]]] = {}
+        actions_by_user: Dict[str, Collection[Union[Mapping, str]]] = {}
 
         room_member_count = await self.store.get_number_joined_users_in_room(
             event.room_id
@@ -317,15 +328,13 @@ class BulkPushRuleEvaluator:
                 # current user, it'll be added to the dict later.
                 actions_by_user[uid] = []
 
-            for rule in rules:
-                if "enabled" in rule and not rule["enabled"]:
+            for rule, enabled in rules:
+                if not enabled:
                     continue
 
-                matches = evaluator.check_conditions(
-                    rule["conditions"], uid, display_name
-                )
+                matches = evaluator.check_conditions(rule.conditions, uid, display_name)
                 if matches:
-                    actions = [x for x in rule["actions"] if x != "dont_notify"]
+                    actions = [x for x in rule.actions if x != "dont_notify"]
                     if actions and "notify" in actions:
                         # Push rules say we should notify the user of this event
                         actions_by_user[uid] = actions
diff --git a/synapse/push/clientformat.py b/synapse/push/clientformat.py
index 5117ef6854..73618d9234 100644
--- a/synapse/push/clientformat.py
+++ b/synapse/push/clientformat.py
@@ -18,16 +18,15 @@ from typing import Any, Dict, List, Optional
 from synapse.push.rulekinds import PRIORITY_CLASS_INVERSE_MAP, PRIORITY_CLASS_MAP
 from synapse.types import UserID
 
+from .baserules import FilteredPushRules, PushRule
+
 
 def format_push_rules_for_user(
-    user: UserID, ruleslist: List
+    user: UserID, ruleslist: FilteredPushRules
 ) -> Dict[str, Dict[str, list]]:
     """Converts a list of rawrules and a enabled map into nested dictionaries
     to match the Matrix client-server format for push rules"""
 
-    # We're going to be mutating this a lot, so do a deep copy
-    ruleslist = copy.deepcopy(ruleslist)
-
     rules: Dict[str, Dict[str, List[Dict[str, Any]]]] = {
         "global": {},
         "device": {},
@@ -35,11 +34,30 @@ def format_push_rules_for_user(
 
     rules["global"] = _add_empty_priority_class_arrays(rules["global"])
 
-    for r in ruleslist:
-        template_name = _priority_class_to_template_name(r["priority_class"])
+    for r, enabled in ruleslist:
+        template_name = _priority_class_to_template_name(r.priority_class)
+
+        rulearray = rules["global"][template_name]
+
+        template_rule = _rule_to_template(r)
+        if not template_rule:
+            continue
+
+        rulearray.append(template_rule)
+
+        template_rule["enabled"] = enabled
+
+        if "conditions" not in template_rule:
+            # Not all formatted rules have explicit conditions, e.g. "room"
+            # rules omit them as they can be derived from the kind and rule ID.
+            #
+            # If the formatted rule has no conditions then we can skip the
+            # formatting of conditions.
+            continue
 
         # Remove internal stuff.
-        for c in r["conditions"]:
+        template_rule["conditions"] = copy.deepcopy(template_rule["conditions"])
+        for c in template_rule["conditions"]:
             c.pop("_cache_key", None)
 
             pattern_type = c.pop("pattern_type", None)
@@ -52,16 +70,6 @@ def format_push_rules_for_user(
             if sender_type == "user_id":
                 c["sender"] = user.to_string()
 
-        rulearray = rules["global"][template_name]
-
-        template_rule = _rule_to_template(r)
-        if template_rule:
-            if "enabled" in r:
-                template_rule["enabled"] = r["enabled"]
-            else:
-                template_rule["enabled"] = True
-            rulearray.append(template_rule)
-
     return rules
 
 
@@ -71,24 +79,24 @@ def _add_empty_priority_class_arrays(d: Dict[str, list]) -> Dict[str, list]:
     return d
 
 
-def _rule_to_template(rule: Dict[str, Any]) -> Optional[Dict[str, Any]]:
-    unscoped_rule_id = None
-    if "rule_id" in rule:
-        unscoped_rule_id = _rule_id_from_namespaced(rule["rule_id"])
+def _rule_to_template(rule: PushRule) -> Optional[Dict[str, Any]]:
+    templaterule: Dict[str, Any]
+
+    unscoped_rule_id = _rule_id_from_namespaced(rule.rule_id)
 
-    template_name = _priority_class_to_template_name(rule["priority_class"])
+    template_name = _priority_class_to_template_name(rule.priority_class)
     if template_name in ["override", "underride"]:
-        templaterule = {k: rule[k] for k in ["conditions", "actions"]}
+        templaterule = {"conditions": rule.conditions, "actions": rule.actions}
     elif template_name in ["sender", "room"]:
-        templaterule = {"actions": rule["actions"]}
-        unscoped_rule_id = rule["conditions"][0]["pattern"]
+        templaterule = {"actions": rule.actions}
+        unscoped_rule_id = rule.conditions[0]["pattern"]
     elif template_name == "content":
-        if len(rule["conditions"]) != 1:
+        if len(rule.conditions) != 1:
             return None
-        thecond = rule["conditions"][0]
+        thecond = rule.conditions[0]
         if "pattern" not in thecond:
             return None
-        templaterule = {"actions": rule["actions"]}
+        templaterule = {"actions": rule.actions}
         templaterule["pattern"] = thecond["pattern"]
     else:
         # This should not be reached unless this function is not kept in sync
@@ -97,8 +105,8 @@ def _rule_to_template(rule: Dict[str, Any]) -> Optional[Dict[str, Any]]:
 
     if unscoped_rule_id:
         templaterule["rule_id"] = unscoped_rule_id
-    if "default" in rule:
-        templaterule["default"] = rule["default"]
+    if rule.default:
+        templaterule["default"] = True
     return templaterule
 
 
diff --git a/synapse/push/push_rule_evaluator.py b/synapse/push/push_rule_evaluator.py
index 2e8a017add..3c5632cd91 100644
--- a/synapse/push/push_rule_evaluator.py
+++ b/synapse/push/push_rule_evaluator.py
@@ -15,7 +15,18 @@
 
 import logging
 import re
-from typing import Any, Dict, List, Mapping, Optional, Pattern, Set, Tuple, Union
+from typing import (
+    Any,
+    Dict,
+    List,
+    Mapping,
+    Optional,
+    Pattern,
+    Sequence,
+    Set,
+    Tuple,
+    Union,
+)
 
 from matrix_common.regex import glob_to_regex, to_word_pattern
 
@@ -32,14 +43,14 @@ INEQUALITY_EXPR = re.compile("^([=<>]*)([0-9]*)$")
 
 
 def _room_member_count(
-    ev: EventBase, condition: Dict[str, Any], room_member_count: int
+    ev: EventBase, condition: Mapping[str, Any], room_member_count: int
 ) -> bool:
     return _test_ineq_condition(condition, room_member_count)
 
 
 def _sender_notification_permission(
     ev: EventBase,
-    condition: Dict[str, Any],
+    condition: Mapping[str, Any],
     sender_power_level: int,
     power_levels: Dict[str, Union[int, Dict[str, int]]],
 ) -> bool:
@@ -54,7 +65,7 @@ def _sender_notification_permission(
     return sender_power_level >= room_notif_level
 
 
-def _test_ineq_condition(condition: Dict[str, Any], number: int) -> bool:
+def _test_ineq_condition(condition: Mapping[str, Any], number: int) -> bool:
     if "is" not in condition:
         return False
     m = INEQUALITY_EXPR.match(condition["is"])
@@ -137,7 +148,7 @@ class PushRuleEvaluatorForEvent:
         self._condition_cache: Dict[str, bool] = {}
 
     def check_conditions(
-        self, conditions: List[dict], uid: str, display_name: Optional[str]
+        self, conditions: Sequence[Mapping], uid: str, display_name: Optional[str]
     ) -> bool:
         """
         Returns true if a user's conditions/user ID/display name match the event.
@@ -169,7 +180,7 @@ class PushRuleEvaluatorForEvent:
         return True
 
     def matches(
-        self, condition: Dict[str, Any], user_id: str, display_name: Optional[str]
+        self, condition: Mapping[str, Any], user_id: str, display_name: Optional[str]
     ) -> bool:
         """
         Returns true if a user's condition/user ID/display name match the event.
@@ -204,7 +215,7 @@ class PushRuleEvaluatorForEvent:
             #     endpoint with an unknown kind, see _rule_tuple_from_request_object.
             return True
 
-    def _event_match(self, condition: dict, user_id: str) -> bool:
+    def _event_match(self, condition: Mapping, user_id: str) -> bool:
         """
         Check an "event_match" push rule condition.
 
@@ -269,7 +280,7 @@ class PushRuleEvaluatorForEvent:
 
         return bool(r.search(body))
 
-    def _relation_match(self, condition: dict, user_id: str) -> bool:
+    def _relation_match(self, condition: Mapping, user_id: str) -> bool:
         """
         Check an "relation_match" push rule condition.
 
diff --git a/synapse/replication/slave/storage/_base.py b/synapse/replication/slave/storage/_base.py
deleted file mode 100644
index 7644146dba..0000000000
--- a/synapse/replication/slave/storage/_base.py
+++ /dev/null
@@ -1,58 +0,0 @@
-# Copyright 2016 OpenMarket Ltd
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-import logging
-from typing import TYPE_CHECKING, Optional
-
-from synapse.storage.database import DatabasePool, LoggingDatabaseConnection
-from synapse.storage.databases.main.cache import CacheInvalidationWorkerStore
-from synapse.storage.engines import PostgresEngine
-from synapse.storage.util.id_generators import MultiWriterIdGenerator
-
-if TYPE_CHECKING:
-    from synapse.server import HomeServer
-
-logger = logging.getLogger(__name__)
-
-
-class BaseSlavedStore(CacheInvalidationWorkerStore):
-    def __init__(
-        self,
-        database: DatabasePool,
-        db_conn: LoggingDatabaseConnection,
-        hs: "HomeServer",
-    ):
-        super().__init__(database, db_conn, hs)
-        if isinstance(self.database_engine, PostgresEngine):
-            self._cache_id_gen: Optional[
-                MultiWriterIdGenerator
-            ] = MultiWriterIdGenerator(
-                db_conn,
-                database,
-                stream_name="caches",
-                instance_name=hs.get_instance_name(),
-                tables=[
-                    (
-                        "cache_invalidation_stream_by_instance",
-                        "instance_name",
-                        "stream_id",
-                    )
-                ],
-                sequence_name="cache_invalidation_stream_seq",
-                writers=[],
-            )
-        else:
-            self._cache_id_gen = None
-
-        self.hs = hs
diff --git a/synapse/replication/slave/storage/account_data.py b/synapse/replication/slave/storage/account_data.py
deleted file mode 100644
index ee74ee7d85..0000000000
--- a/synapse/replication/slave/storage/account_data.py
+++ /dev/null
@@ -1,22 +0,0 @@
-# Copyright 2016 OpenMarket Ltd
-# Copyright 2018 New Vector Ltd
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-from synapse.replication.slave.storage._base import BaseSlavedStore
-from synapse.storage.databases.main.account_data import AccountDataWorkerStore
-from synapse.storage.databases.main.tags import TagsWorkerStore
-
-
-class SlavedAccountDataStore(TagsWorkerStore, AccountDataWorkerStore, BaseSlavedStore):
-    pass
diff --git a/synapse/replication/slave/storage/appservice.py b/synapse/replication/slave/storage/appservice.py
deleted file mode 100644
index 29f50c0add..0000000000
--- a/synapse/replication/slave/storage/appservice.py
+++ /dev/null
@@ -1,25 +0,0 @@
-# Copyright 2015, 2016 OpenMarket Ltd
-# Copyright 2018 New Vector Ltd
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-from synapse.storage.databases.main.appservice import (
-    ApplicationServiceTransactionWorkerStore,
-    ApplicationServiceWorkerStore,
-)
-
-
-class SlavedApplicationServiceStore(
-    ApplicationServiceTransactionWorkerStore, ApplicationServiceWorkerStore
-):
-    pass
diff --git a/synapse/replication/slave/storage/deviceinbox.py b/synapse/replication/slave/storage/deviceinbox.py
deleted file mode 100644
index e940751084..0000000000
--- a/synapse/replication/slave/storage/deviceinbox.py
+++ /dev/null
@@ -1,20 +0,0 @@
-# Copyright 2016 OpenMarket Ltd
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-from synapse.replication.slave.storage._base import BaseSlavedStore
-from synapse.storage.databases.main.deviceinbox import DeviceInboxWorkerStore
-
-
-class SlavedDeviceInboxStore(DeviceInboxWorkerStore, BaseSlavedStore):
-    pass
diff --git a/synapse/replication/slave/storage/devices.py b/synapse/replication/slave/storage/devices.py
index a48cc02069..6fcade510a 100644
--- a/synapse/replication/slave/storage/devices.py
+++ b/synapse/replication/slave/storage/devices.py
@@ -14,7 +14,6 @@
 
 from typing import TYPE_CHECKING, Any, Iterable
 
-from synapse.replication.slave.storage._base import BaseSlavedStore
 from synapse.replication.slave.storage._slaved_id_tracker import SlavedIdTracker
 from synapse.replication.tcp.streams._base import DeviceListsStream, UserSignatureStream
 from synapse.storage.database import DatabasePool, LoggingDatabaseConnection
@@ -24,7 +23,7 @@ if TYPE_CHECKING:
     from synapse.server import HomeServer
 
 
-class SlavedDeviceStore(DeviceWorkerStore, BaseSlavedStore):
+class SlavedDeviceStore(DeviceWorkerStore):
     def __init__(
         self,
         database: DatabasePool,
diff --git a/synapse/replication/slave/storage/directory.py b/synapse/replication/slave/storage/directory.py
deleted file mode 100644
index 71fde0c96c..0000000000
--- a/synapse/replication/slave/storage/directory.py
+++ /dev/null
@@ -1,21 +0,0 @@
-# Copyright 2015, 2016 OpenMarket Ltd
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-from synapse.storage.databases.main.directory import DirectoryWorkerStore
-
-from ._base import BaseSlavedStore
-
-
-class DirectoryStore(DirectoryWorkerStore, BaseSlavedStore):
-    pass
diff --git a/synapse/replication/slave/storage/events.py b/synapse/replication/slave/storage/events.py
index a72dad7464..fe47778cb1 100644
--- a/synapse/replication/slave/storage/events.py
+++ b/synapse/replication/slave/storage/events.py
@@ -29,8 +29,6 @@ from synapse.storage.databases.main.stream import StreamWorkerStore
 from synapse.storage.databases.main.user_erasure_store import UserErasureWorkerStore
 from synapse.util.caches.stream_change_cache import StreamChangeCache
 
-from ._base import BaseSlavedStore
-
 if TYPE_CHECKING:
     from synapse.server import HomeServer
 
@@ -56,7 +54,6 @@ class SlavedEventStore(
     EventsWorkerStore,
     UserErasureWorkerStore,
     RelationsWorkerStore,
-    BaseSlavedStore,
 ):
     def __init__(
         self,
diff --git a/synapse/replication/slave/storage/filtering.py b/synapse/replication/slave/storage/filtering.py
index 4d185e2b56..c52679cd60 100644
--- a/synapse/replication/slave/storage/filtering.py
+++ b/synapse/replication/slave/storage/filtering.py
@@ -14,16 +14,15 @@
 
 from typing import TYPE_CHECKING
 
+from synapse.storage._base import SQLBaseStore
 from synapse.storage.database import DatabasePool, LoggingDatabaseConnection
 from synapse.storage.databases.main.filtering import FilteringStore
 
-from ._base import BaseSlavedStore
-
 if TYPE_CHECKING:
     from synapse.server import HomeServer
 
 
-class SlavedFilteringStore(BaseSlavedStore):
+class SlavedFilteringStore(SQLBaseStore):
     def __init__(
         self,
         database: DatabasePool,
diff --git a/synapse/replication/slave/storage/profile.py b/synapse/replication/slave/storage/profile.py
deleted file mode 100644
index 99f4a22642..0000000000
--- a/synapse/replication/slave/storage/profile.py
+++ /dev/null
@@ -1,20 +0,0 @@
-# Copyright 2018 New Vector Ltd
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-from synapse.replication.slave.storage._base import BaseSlavedStore
-from synapse.storage.databases.main.profile import ProfileWorkerStore
-
-
-class SlavedProfileStore(ProfileWorkerStore, BaseSlavedStore):
-    pass
diff --git a/synapse/replication/slave/storage/push_rule.py b/synapse/replication/slave/storage/push_rule.py
index 52ee3f7e58..5e65eaf1e0 100644
--- a/synapse/replication/slave/storage/push_rule.py
+++ b/synapse/replication/slave/storage/push_rule.py
@@ -31,6 +31,5 @@ class SlavedPushRuleStore(SlavedEventStore, PushRulesWorkerStore):
             self._push_rules_stream_id_gen.advance(instance_name, token)
             for row in rows:
                 self.get_push_rules_for_user.invalidate((row.user_id,))
-                self.get_push_rules_enabled_for_user.invalidate((row.user_id,))
                 self.push_rules_stream_cache.entity_has_changed(row.user_id, token)
         return super().process_replication_rows(stream_name, instance_name, token, rows)
diff --git a/synapse/replication/slave/storage/pushers.py b/synapse/replication/slave/storage/pushers.py
index de642bba71..44ed20e424 100644
--- a/synapse/replication/slave/storage/pushers.py
+++ b/synapse/replication/slave/storage/pushers.py
@@ -18,14 +18,13 @@ from synapse.replication.tcp.streams import PushersStream
 from synapse.storage.database import DatabasePool, LoggingDatabaseConnection
 from synapse.storage.databases.main.pusher import PusherWorkerStore
 
-from ._base import BaseSlavedStore
 from ._slaved_id_tracker import SlavedIdTracker
 
 if TYPE_CHECKING:
     from synapse.server import HomeServer
 
 
-class SlavedPusherStore(PusherWorkerStore, BaseSlavedStore):
+class SlavedPusherStore(PusherWorkerStore):
     def __init__(
         self,
         database: DatabasePool,
diff --git a/synapse/replication/slave/storage/receipts.py b/synapse/replication/slave/storage/receipts.py
deleted file mode 100644
index 3826b87dec..0000000000
--- a/synapse/replication/slave/storage/receipts.py
+++ /dev/null
@@ -1,22 +0,0 @@
-# Copyright 2016 OpenMarket Ltd
-# Copyright 2018 New Vector Ltd
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-from synapse.storage.databases.main.receipts import ReceiptsWorkerStore
-
-from ._base import BaseSlavedStore
-
-
-class SlavedReceiptsStore(ReceiptsWorkerStore, BaseSlavedStore):
-    pass
diff --git a/synapse/replication/slave/storage/registration.py b/synapse/replication/slave/storage/registration.py
deleted file mode 100644
index 5dae35a960..0000000000
--- a/synapse/replication/slave/storage/registration.py
+++ /dev/null
@@ -1,21 +0,0 @@
-# Copyright 2015, 2016 OpenMarket Ltd
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-from synapse.storage.databases.main.registration import RegistrationWorkerStore
-
-from ._base import BaseSlavedStore
-
-
-class SlavedRegistrationStore(RegistrationWorkerStore, BaseSlavedStore):
-    pass
diff --git a/synapse/replication/tcp/client.py b/synapse/replication/tcp/client.py
index e4f2201c92..1ed7230e32 100644
--- a/synapse/replication/tcp/client.py
+++ b/synapse/replication/tcp/client.py
@@ -416,7 +416,10 @@ class FederationSenderHandler:
             if not self._is_mine_id(receipt.user_id):
                 continue
             # Private read receipts never get sent over federation.
-            if receipt.receipt_type == ReceiptTypes.READ_PRIVATE:
+            if receipt.receipt_type in (
+                ReceiptTypes.READ_PRIVATE,
+                ReceiptTypes.UNSTABLE_READ_PRIVATE,
+            ):
                 continue
             receipt_info = ReadReceipt(
                 receipt.room_id,
diff --git a/synapse/res/templates/account_previously_renewed.html b/synapse/res/templates/account_previously_renewed.html
index b751359bdf..bd4f7cea97 100644
--- a/synapse/res/templates/account_previously_renewed.html
+++ b/synapse/res/templates/account_previously_renewed.html
@@ -1 +1,12 @@
-<html><body>Your account is valid until {{ expiration_ts|format_ts("%d-%m-%Y") }}.</body><html>
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Your account is valid until {{ expiration_ts|format_ts("%d-%m-%Y") }}.</title>
+</head>
+<body>
+    Your account is valid until {{ expiration_ts|format_ts("%d-%m-%Y") }}.
+</body>
+</html>
\ No newline at end of file
diff --git a/synapse/res/templates/account_renewed.html b/synapse/res/templates/account_renewed.html
index e8c0f52f05..57b319f375 100644
--- a/synapse/res/templates/account_renewed.html
+++ b/synapse/res/templates/account_renewed.html
@@ -1 +1,12 @@
-<html><body>Your account has been successfully renewed and is valid until {{ expiration_ts|format_ts("%d-%m-%Y") }}.</body><html>
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Your account has been successfully renewed and is valid until {{ expiration_ts|format_ts("%d-%m-%Y") }}.</title>
+</head>
+<body>
+    Your account has been successfully renewed and is valid until {{ expiration_ts|format_ts("%d-%m-%Y") }}.
+</body>
+</html>
\ No newline at end of file
diff --git a/synapse/res/templates/add_threepid.html b/synapse/res/templates/add_threepid.html
index cc4ab07e09..71f2215b7a 100644
--- a/synapse/res/templates/add_threepid.html
+++ b/synapse/res/templates/add_threepid.html
@@ -1,9 +1,14 @@
-<html>
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Request to add an email address to your Matrix account</title>
+</head>
 <body>
     <p>A request to add an email address to your Matrix account has been received. If this was you, please click the link below to confirm adding this email:</p>
-
     <a href="{{ link }}">{{ link }}</a>
-
     <p>If this was not you, you can safely ignore this email. Thank you.</p>
 </body>
 </html>
diff --git a/synapse/res/templates/add_threepid_failure.html b/synapse/res/templates/add_threepid_failure.html
index 441d11c846..bd627ee9ce 100644
--- a/synapse/res/templates/add_threepid_failure.html
+++ b/synapse/res/templates/add_threepid_failure.html
@@ -1,8 +1,13 @@
-<html>
-<head></head>
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Request failed</title>
+</head>
 <body>
-<p>The request failed for the following reason: {{ failure_reason }}.</p>
-
-<p>No changes have been made to your account.</p>
+    <p>The request failed for the following reason: {{ failure_reason }}.</p>
+    <p>No changes have been made to your account.</p>
 </body>
 </html>
diff --git a/synapse/res/templates/add_threepid_success.html b/synapse/res/templates/add_threepid_success.html
index fbd6e4018f..49170c138e 100644
--- a/synapse/res/templates/add_threepid_success.html
+++ b/synapse/res/templates/add_threepid_success.html
@@ -1,6 +1,12 @@
-<html>
-<head></head>
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Your email has now been validated</title>
+</head>
 <body>
-<p>Your email has now been validated, please return to your client. You may now close this window.</p>
+    <p>Your email has now been validated, please return to your client. You may now close this window.</p>
 </body>
-</html>
+</html>
\ No newline at end of file
diff --git a/synapse/res/templates/auth_success.html b/synapse/res/templates/auth_success.html
index baf4633142..2d6ac44a0e 100644
--- a/synapse/res/templates/auth_success.html
+++ b/synapse/res/templates/auth_success.html
@@ -1,8 +1,8 @@
 <html>
 <head>
 <title>Success!</title>
-<meta name='viewport' content='width=device-width, initial-scale=1,
-    user-scalable=no, minimum-scale=1.0, maximum-scale=1.0'>
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
 <link rel="stylesheet" href="/_matrix/static/client/register/style.css">
 <script>
 if (window.onAuthDone) {
diff --git a/synapse/res/templates/invalid_token.html b/synapse/res/templates/invalid_token.html
index 6bd2b98364..2c7c384fe3 100644
--- a/synapse/res/templates/invalid_token.html
+++ b/synapse/res/templates/invalid_token.html
@@ -1 +1,12 @@
-<html><body>Invalid renewal token.</body><html>
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Invalid renewal token.</title>
+</head>
+<body>
+    Invalid renewal token.
+</body>
+</html>
diff --git a/synapse/res/templates/notice_expiry.html b/synapse/res/templates/notice_expiry.html
index d87311f659..865f9f7ada 100644
--- a/synapse/res/templates/notice_expiry.html
+++ b/synapse/res/templates/notice_expiry.html
@@ -1,6 +1,8 @@
 <!doctype html>
 <html lang="en">
     <head>
+        <meta http-equiv="X-UA-Compatible" content="IE=edge">
+        <meta name="viewport" content="width=device-width, initial-scale=1.0">
         <style type="text/css">
             {% include 'mail.css' without context %}
             {% include "mail-%s.css" % app_name ignore missing without context %}
diff --git a/synapse/res/templates/notif_mail.html b/synapse/res/templates/notif_mail.html
index 27d4182790..9dba0c0253 100644
--- a/synapse/res/templates/notif_mail.html
+++ b/synapse/res/templates/notif_mail.html
@@ -1,6 +1,8 @@
 <!doctype html>
 <html lang="en">
     <head>
+        <meta http-equiv="X-UA-Compatible" content="IE=edge">
+        <meta name="viewport" content="width=device-width, initial-scale=1.0">
         <style type="text/css">
             {%- include 'mail.css' without context %}
             {%- include "mail-%s.css" % app_name ignore missing without context %}
diff --git a/synapse/res/templates/password_reset.html b/synapse/res/templates/password_reset.html
index a197bf872c..a8bdce357b 100644
--- a/synapse/res/templates/password_reset.html
+++ b/synapse/res/templates/password_reset.html
@@ -1,4 +1,9 @@
-<html>
+<html lang="en">
+    <head>
+        <title>Password reset</title>
+        <meta http-equiv="X-UA-Compatible" content="IE=edge">
+        <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    </head>
 <body>
     <p>A password reset request has been received for your Matrix account. If this was you, please click the link below to confirm resetting your password:</p>
 
diff --git a/synapse/res/templates/password_reset_confirmation.html b/synapse/res/templates/password_reset_confirmation.html
index def4b5162b..2e3fd2ec1e 100644
--- a/synapse/res/templates/password_reset_confirmation.html
+++ b/synapse/res/templates/password_reset_confirmation.html
@@ -1,5 +1,9 @@
-<html>
-<head></head>
+<html lang="en">
+<head>
+    <title>Password reset confirmation</title>
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+</head>
 <body>
 <!--Use a hidden form to resubmit the information necessary to reset the password-->
 <form method="post">
diff --git a/synapse/res/templates/password_reset_failure.html b/synapse/res/templates/password_reset_failure.html
index 9e3c4446e3..2d59c463f0 100644
--- a/synapse/res/templates/password_reset_failure.html
+++ b/synapse/res/templates/password_reset_failure.html
@@ -1,5 +1,9 @@
-<html>
-<head></head>
+<html lang="en">
+<head>
+    <title>Password reset failure</title>
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+</head>
 <body>
 <p>The request failed for the following reason: {{ failure_reason }}.</p>
 
diff --git a/synapse/res/templates/password_reset_success.html b/synapse/res/templates/password_reset_success.html
index 7324d66d1e..5165bd1fa2 100644
--- a/synapse/res/templates/password_reset_success.html
+++ b/synapse/res/templates/password_reset_success.html
@@ -1,5 +1,8 @@
-<html>
-<head></head>
+<html lang="en">
+<head>
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+</head>
 <body>
 <p>Your email has now been validated, please return to your client to reset your password. You may now close this window.</p>
 </body>
diff --git a/synapse/res/templates/recaptcha.html b/synapse/res/templates/recaptcha.html
index b3db06ef97..615d3239c6 100644
--- a/synapse/res/templates/recaptcha.html
+++ b/synapse/res/templates/recaptcha.html
@@ -1,8 +1,8 @@
 <html>
 <head>
 <title>Authentication</title>
-<meta name='viewport' content='width=device-width, initial-scale=1,
-    user-scalable=no, minimum-scale=1.0, maximum-scale=1.0'>
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
 <script src="https://www.recaptcha.net/recaptcha/api.js"
     async defer></script>
 <script src="//code.jquery.com/jquery-1.11.2.min.js"></script>
diff --git a/synapse/res/templates/registration.html b/synapse/res/templates/registration.html
index 16730a527f..20e831ff4a 100644
--- a/synapse/res/templates/registration.html
+++ b/synapse/res/templates/registration.html
@@ -1,4 +1,9 @@
-<html>
+<html lang="en">
+<head>
+    <title>Registration</title>
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+</head>
 <body>
     <p>You have asked us to register this email with a new Matrix account. If this was you, please click the link below to confirm your email address:</p>
 
diff --git a/synapse/res/templates/registration_failure.html b/synapse/res/templates/registration_failure.html
index 2833d79c37..a6ed22bc90 100644
--- a/synapse/res/templates/registration_failure.html
+++ b/synapse/res/templates/registration_failure.html
@@ -1,5 +1,8 @@
-<html>
-<head></head>
+<html lang="en">
+<head>
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+</head>
 <body>
 <p>Validation failed for the following reason: {{ failure_reason }}.</p>
 </body>
diff --git a/synapse/res/templates/registration_success.html b/synapse/res/templates/registration_success.html
index fbd6e4018f..d51d5549d8 100644
--- a/synapse/res/templates/registration_success.html
+++ b/synapse/res/templates/registration_success.html
@@ -1,5 +1,9 @@
-<html>
-<head></head>
+<html lang="en">
+<head>
+    <title>Your email has now been validated</title>
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+</head>
 <body>
 <p>Your email has now been validated, please return to your client. You may now close this window.</p>
 </body>
diff --git a/synapse/res/templates/registration_token.html b/synapse/res/templates/registration_token.html
index 4577ce1702..59a98f564c 100644
--- a/synapse/res/templates/registration_token.html
+++ b/synapse/res/templates/registration_token.html
@@ -1,8 +1,8 @@
-<html>
+<html lang="en">
 <head>
 <title>Authentication</title>
-<meta name='viewport' content='width=device-width, initial-scale=1,
-    user-scalable=no, minimum-scale=1.0, maximum-scale=1.0'>
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
 <link rel="stylesheet" href="/_matrix/static/client/register/style.css">
 </head>
 <body>
diff --git a/synapse/res/templates/sso_account_deactivated.html b/synapse/res/templates/sso_account_deactivated.html
index c3e4deed93..075f801cec 100644
--- a/synapse/res/templates/sso_account_deactivated.html
+++ b/synapse/res/templates/sso_account_deactivated.html
@@ -3,8 +3,8 @@
     <head>
         <meta charset="UTF-8">
         <title>SSO account deactivated</title>
-        <meta name="viewport" content="width=device-width, user-scalable=no">
-        <style type="text/css">
+        <meta http-equiv="X-UA-Compatible" content="IE=edge">
+        <meta name="viewport" content="width=device-width, initial-scale=1.0">        <style type="text/css">
             {% include "sso.css" without context %}
         </style>
     </head>
diff --git a/synapse/res/templates/sso_auth_account_details.html b/synapse/res/templates/sso_auth_account_details.html
index 1ba850369a..2d1db386e1 100644
--- a/synapse/res/templates/sso_auth_account_details.html
+++ b/synapse/res/templates/sso_auth_account_details.html
@@ -3,7 +3,8 @@
   <head>
     <title>Create your account</title>
     <meta charset="utf-8">
-    <meta name="viewport" content="width=device-width, user-scalable=no">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <script type="text/javascript">
       let wasKeyboard = false;
       document.addEventListener("mousedown", function() { wasKeyboard = false; });
@@ -138,7 +139,7 @@
         <div class="username_input" id="username_input">
           <label for="field-username">Username (required)</label>
           <div class="prefix">@</div>
-          <input type="text" name="username" id="field-username" value="{{ user_attributes.localpart }}" autofocus>
+          <input type="text" name="username" id="field-username" value="{{ user_attributes.localpart }}" autofocus autocorrect="off" autocapitalize="none">
           <div class="postfix">:{{ server_name }}</div>
         </div>
         <output for="username_input" id="field-username-output"></output>
diff --git a/synapse/res/templates/sso_auth_bad_user.html b/synapse/res/templates/sso_auth_bad_user.html
index da579ffe69..94403fc3ce 100644
--- a/synapse/res/templates/sso_auth_bad_user.html
+++ b/synapse/res/templates/sso_auth_bad_user.html
@@ -3,7 +3,8 @@
     <head>
         <meta charset="UTF-8">
         <title>Authentication failed</title>
-        <meta name="viewport" content="width=device-width, user-scalable=no">
+        <meta http-equiv="X-UA-Compatible" content="IE=edge">
+        <meta name="viewport" content="width=device-width, initial-scale=1.0">
         <style type="text/css">
             {% include "sso.css" without context %}
         </style>
diff --git a/synapse/res/templates/sso_auth_confirm.html b/synapse/res/templates/sso_auth_confirm.html
index f9d0456f0a..aa1c974a6b 100644
--- a/synapse/res/templates/sso_auth_confirm.html
+++ b/synapse/res/templates/sso_auth_confirm.html
@@ -3,7 +3,8 @@
     <head>
         <meta charset="UTF-8">
         <title>Confirm it's you</title>
-        <meta name="viewport" content="width=device-width, user-scalable=no">
+        <meta http-equiv="X-UA-Compatible" content="IE=edge">
+        <meta name="viewport" content="width=device-width, initial-scale=1.0">
         <style type="text/css">
             {% include "sso.css" without context %}
         </style>
diff --git a/synapse/res/templates/sso_auth_success.html b/synapse/res/templates/sso_auth_success.html
index 1ed3967e87..4898af6011 100644
--- a/synapse/res/templates/sso_auth_success.html
+++ b/synapse/res/templates/sso_auth_success.html
@@ -3,7 +3,8 @@
     <head>
         <meta charset="UTF-8">
         <title>Authentication successful</title>
-        <meta name="viewport" content="width=device-width, user-scalable=no">
+        <meta http-equiv="X-UA-Compatible" content="IE=edge">
+        <meta name="viewport" content="width=device-width, initial-scale=1.0">
         <style type="text/css">
             {% include "sso.css" without context %}
         </style>
diff --git a/synapse/res/templates/sso_error.html b/synapse/res/templates/sso_error.html
index 472309c350..19992ff2ad 100644
--- a/synapse/res/templates/sso_error.html
+++ b/synapse/res/templates/sso_error.html
@@ -3,7 +3,8 @@
     <head>
         <meta charset="UTF-8">
         <title>Authentication failed</title>
-        <meta name="viewport" content="width=device-width, user-scalable=no">
+        <meta http-equiv="X-UA-Compatible" content="IE=edge">
+        <meta name="viewport" content="width=device-width, initial-scale=1.0">
         <style type="text/css">
             {% include "sso.css" without context %}
 
diff --git a/synapse/res/templates/sso_login_idp_picker.html b/synapse/res/templates/sso_login_idp_picker.html
index 53b82db84e..56fabfa3d2 100644
--- a/synapse/res/templates/sso_login_idp_picker.html
+++ b/synapse/res/templates/sso_login_idp_picker.html
@@ -1,6 +1,8 @@
 <!DOCTYPE html>
 <html lang="en">
     <head>
+        <meta http-equiv="X-UA-Compatible" content="IE=edge">
+        <meta name="viewport" content="width=device-width, initial-scale=1.0">
         <meta charset="UTF-8">
         <title>Choose identity provider</title>
         <style type="text/css">
diff --git a/synapse/res/templates/sso_new_user_consent.html b/synapse/res/templates/sso_new_user_consent.html
index 68c8b9f33a..523f64c4fc 100644
--- a/synapse/res/templates/sso_new_user_consent.html
+++ b/synapse/res/templates/sso_new_user_consent.html
@@ -3,7 +3,8 @@
 <head>
     <meta charset="UTF-8">
     <title>Agree to terms and conditions</title>
-    <meta name="viewport" content="width=device-width, user-scalable=no">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <style type="text/css">
       {% include "sso.css" without context %}
 
diff --git a/synapse/res/templates/sso_redirect_confirm.html b/synapse/res/templates/sso_redirect_confirm.html
index 1b01471ac8..1049a9bd92 100644
--- a/synapse/res/templates/sso_redirect_confirm.html
+++ b/synapse/res/templates/sso_redirect_confirm.html
@@ -3,7 +3,8 @@
 <head>
     <meta charset="UTF-8">
     <title>Continue to your account</title>
-    <meta name="viewport" content="width=device-width, user-scalable=no">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <style type="text/css">
       {% include "sso.css" without context %}
 
diff --git a/synapse/res/templates/terms.html b/synapse/res/templates/terms.html
index 369ff446d2..2081d990ab 100644
--- a/synapse/res/templates/terms.html
+++ b/synapse/res/templates/terms.html
@@ -1,8 +1,8 @@
 <html>
 <head>
 <title>Authentication</title>
-<meta name='viewport' content='width=device-width, initial-scale=1,
-    user-scalable=no, minimum-scale=1.0, maximum-scale=1.0'>
+<meta http-equiv="X-UA-Compatible" content="IE=edge">
+<meta name="viewport" content="width=device-width, initial-scale=1.0">
 <link rel="stylesheet" href="/_matrix/static/client/register/style.css">
 </head>
 <body>
diff --git a/synapse/rest/admin/_base.py b/synapse/rest/admin/_base.py
index 399b205aaf..b467a61dfb 100644
--- a/synapse/rest/admin/_base.py
+++ b/synapse/rest/admin/_base.py
@@ -19,7 +19,7 @@ from typing import Iterable, Pattern
 from synapse.api.auth import Auth
 from synapse.api.errors import AuthError
 from synapse.http.site import SynapseRequest
-from synapse.types import UserID
+from synapse.types import Requester
 
 
 def admin_patterns(path_regex: str, version: str = "v1") -> Iterable[Pattern]:
@@ -48,19 +48,19 @@ async def assert_requester_is_admin(auth: Auth, request: SynapseRequest) -> None
         AuthError if the requester is not a server admin
     """
     requester = await auth.get_user_by_req(request)
-    await assert_user_is_admin(auth, requester.user)
+    await assert_user_is_admin(auth, requester)
 
 
-async def assert_user_is_admin(auth: Auth, user_id: UserID) -> None:
+async def assert_user_is_admin(auth: Auth, requester: Requester) -> None:
     """Verify that the given user is an admin user
 
     Args:
         auth: Auth singleton
-        user_id: user to check
+        requester: The user making the request, according to the access token.
 
     Raises:
         AuthError if the user is not a server admin
     """
-    is_admin = await auth.is_server_admin(user_id)
+    is_admin = await auth.is_server_admin(requester)
     if not is_admin:
         raise AuthError(HTTPStatus.FORBIDDEN, "You are not a server admin")
diff --git a/synapse/rest/admin/media.py b/synapse/rest/admin/media.py
index 19d4a008e8..73470f09ae 100644
--- a/synapse/rest/admin/media.py
+++ b/synapse/rest/admin/media.py
@@ -54,7 +54,7 @@ class QuarantineMediaInRoom(RestServlet):
         self, request: SynapseRequest, room_id: str
     ) -> Tuple[int, JsonDict]:
         requester = await self.auth.get_user_by_req(request)
-        await assert_user_is_admin(self.auth, requester.user)
+        await assert_user_is_admin(self.auth, requester)
 
         logging.info("Quarantining room: %s", room_id)
 
@@ -81,7 +81,7 @@ class QuarantineMediaByUser(RestServlet):
         self, request: SynapseRequest, user_id: str
     ) -> Tuple[int, JsonDict]:
         requester = await self.auth.get_user_by_req(request)
-        await assert_user_is_admin(self.auth, requester.user)
+        await assert_user_is_admin(self.auth, requester)
 
         logging.info("Quarantining media by user: %s", user_id)
 
@@ -110,7 +110,7 @@ class QuarantineMediaByID(RestServlet):
         self, request: SynapseRequest, server_name: str, media_id: str
     ) -> Tuple[int, JsonDict]:
         requester = await self.auth.get_user_by_req(request)
-        await assert_user_is_admin(self.auth, requester.user)
+        await assert_user_is_admin(self.auth, requester)
 
         logging.info("Quarantining media by ID: %s/%s", server_name, media_id)
 
diff --git a/synapse/rest/admin/rooms.py b/synapse/rest/admin/rooms.py
index 9d953d58de..3d870629c4 100644
--- a/synapse/rest/admin/rooms.py
+++ b/synapse/rest/admin/rooms.py
@@ -75,7 +75,7 @@ class RoomRestV2Servlet(RestServlet):
     ) -> Tuple[int, JsonDict]:
 
         requester = await self._auth.get_user_by_req(request)
-        await assert_user_is_admin(self._auth, requester.user)
+        await assert_user_is_admin(self._auth, requester)
 
         content = parse_json_object_from_request(request)
 
@@ -303,6 +303,7 @@ class RoomRestServlet(RestServlet):
 
         members = await self.store.get_users_in_room(room_id)
         ret["joined_local_devices"] = await self.store.count_devices_by_users(members)
+        ret["forgotten"] = await self.store.is_locally_forgotten_room(room_id)
 
         return HTTPStatus.OK, ret
 
@@ -326,7 +327,7 @@ class RoomRestServlet(RestServlet):
         pagination_handler: "PaginationHandler",
     ) -> Tuple[int, JsonDict]:
         requester = await auth.get_user_by_req(request)
-        await assert_user_is_admin(auth, requester.user)
+        await assert_user_is_admin(auth, requester)
 
         content = parse_json_object_from_request(request)
 
@@ -460,7 +461,7 @@ class JoinRoomAliasServlet(ResolveRoomIdMixin, RestServlet):
         assert request.args is not None
 
         requester = await self.auth.get_user_by_req(request)
-        await assert_user_is_admin(self.auth, requester.user)
+        await assert_user_is_admin(self.auth, requester)
 
         content = parse_json_object_from_request(request)
 
@@ -550,7 +551,7 @@ class MakeRoomAdminRestServlet(ResolveRoomIdMixin, RestServlet):
         self, request: SynapseRequest, room_identifier: str
     ) -> Tuple[int, JsonDict]:
         requester = await self.auth.get_user_by_req(request)
-        await assert_user_is_admin(self.auth, requester.user)
+        await assert_user_is_admin(self.auth, requester)
         content = parse_json_object_from_request(request, allow_empty_body=True)
 
         room_id, _ = await self.resolve_room_id(room_identifier)
@@ -741,7 +742,7 @@ class RoomEventContextServlet(RestServlet):
         self, request: SynapseRequest, room_id: str, event_id: str
     ) -> Tuple[int, JsonDict]:
         requester = await self.auth.get_user_by_req(request, allow_guest=False)
-        await assert_user_is_admin(self.auth, requester.user)
+        await assert_user_is_admin(self.auth, requester)
 
         limit = parse_integer(request, "limit", default=10)
 
@@ -833,7 +834,7 @@ class BlockRoomRestServlet(RestServlet):
         self, request: SynapseRequest, room_id: str
     ) -> Tuple[int, JsonDict]:
         requester = await self._auth.get_user_by_req(request)
-        await assert_user_is_admin(self._auth, requester.user)
+        await assert_user_is_admin(self._auth, requester)
 
         content = parse_json_object_from_request(request)
 
diff --git a/synapse/rest/admin/users.py b/synapse/rest/admin/users.py
index ba2f7fa6d8..78ee9b6532 100644
--- a/synapse/rest/admin/users.py
+++ b/synapse/rest/admin/users.py
@@ -183,7 +183,7 @@ class UserRestServletV2(RestServlet):
         self, request: SynapseRequest, user_id: str
     ) -> Tuple[int, JsonDict]:
         requester = await self.auth.get_user_by_req(request)
-        await assert_user_is_admin(self.auth, requester.user)
+        await assert_user_is_admin(self.auth, requester)
 
         target_user = UserID.from_string(user_id)
         body = parse_json_object_from_request(request)
@@ -575,10 +575,9 @@ class WhoisRestServlet(RestServlet):
     ) -> Tuple[int, JsonDict]:
         target_user = UserID.from_string(user_id)
         requester = await self.auth.get_user_by_req(request)
-        auth_user = requester.user
 
-        if target_user != auth_user:
-            await assert_user_is_admin(self.auth, auth_user)
+        if target_user != requester.user:
+            await assert_user_is_admin(self.auth, requester)
 
         if not self.is_mine(target_user):
             raise SynapseError(HTTPStatus.BAD_REQUEST, "Can only whois a local user")
@@ -601,7 +600,7 @@ class DeactivateAccountRestServlet(RestServlet):
         self, request: SynapseRequest, target_user_id: str
     ) -> Tuple[int, JsonDict]:
         requester = await self.auth.get_user_by_req(request)
-        await assert_user_is_admin(self.auth, requester.user)
+        await assert_user_is_admin(self.auth, requester)
 
         if not self.is_mine(UserID.from_string(target_user_id)):
             raise SynapseError(
@@ -693,7 +692,7 @@ class ResetPasswordRestServlet(RestServlet):
         This needs user to have administrator access in Synapse.
         """
         requester = await self.auth.get_user_by_req(request)
-        await assert_user_is_admin(self.auth, requester.user)
+        await assert_user_is_admin(self.auth, requester)
 
         UserID.from_string(target_user_id)
 
@@ -807,7 +806,7 @@ class UserAdminServlet(RestServlet):
         self, request: SynapseRequest, user_id: str
     ) -> Tuple[int, JsonDict]:
         requester = await self.auth.get_user_by_req(request)
-        await assert_user_is_admin(self.auth, requester.user)
+        await assert_user_is_admin(self.auth, requester)
         auth_user = requester.user
 
         target_user = UserID.from_string(user_id)
@@ -921,7 +920,7 @@ class UserTokenRestServlet(RestServlet):
         self, request: SynapseRequest, user_id: str
     ) -> Tuple[int, JsonDict]:
         requester = await self.auth.get_user_by_req(request)
-        await assert_user_is_admin(self.auth, requester.user)
+        await assert_user_is_admin(self.auth, requester)
         auth_user = requester.user
 
         if not self.is_mine_id(user_id):
diff --git a/synapse/rest/client/account.py b/synapse/rest/client/account.py
index 0cc87a4001..1f9a8ccc23 100644
--- a/synapse/rest/client/account.py
+++ b/synapse/rest/client/account.py
@@ -15,10 +15,11 @@
 # limitations under the License.
 import logging
 import random
-from http import HTTPStatus
 from typing import TYPE_CHECKING, Optional, Tuple
 from urllib.parse import urlparse
 
+from pydantic import StrictBool, StrictStr, constr
+
 from twisted.web.server import Request
 
 from synapse.api.constants import LoginType
@@ -33,12 +34,15 @@ from synapse.http.server import HttpServer, finish_request, respond_with_html
 from synapse.http.servlet import (
     RestServlet,
     assert_params_in_dict,
+    parse_and_validate_json_object_from_request,
     parse_json_object_from_request,
     parse_string,
 )
 from synapse.http.site import SynapseRequest
 from synapse.metrics import threepid_send_requests
 from synapse.push.mailer import Mailer
+from synapse.rest.client.models import AuthenticationData, EmailRequestTokenBody
+from synapse.rest.models import RequestBodyModel
 from synapse.types import JsonDict
 from synapse.util.msisdn import phone_number_to_msisdn
 from synapse.util.stringutils import assert_valid_client_secret, random_string
@@ -80,32 +84,16 @@ class EmailPasswordRequestTokenRestServlet(RestServlet):
                 400, "Email-based password resets have been disabled on this server"
             )
 
-        body = parse_json_object_from_request(request)
-
-        assert_params_in_dict(body, ["client_secret", "email", "send_attempt"])
-
-        # Extract params from body
-        client_secret = body["client_secret"]
-        assert_valid_client_secret(client_secret)
-
-        # Canonicalise the email address. The addresses are all stored canonicalised
-        # in the database. This allows the user to reset his password without having to
-        # know the exact spelling (eg. upper and lower case) of address in the database.
-        # Stored in the database "foo@bar.com"
-        # User requests with "FOO@bar.com" would raise a Not Found error
-        try:
-            email = validate_email(body["email"])
-        except ValueError as e:
-            raise SynapseError(400, str(e))
-        send_attempt = body["send_attempt"]
-        next_link = body.get("next_link")  # Optional param
+        body = parse_and_validate_json_object_from_request(
+            request, EmailRequestTokenBody
+        )
 
-        if next_link:
+        if body.next_link:
             # Raise if the provided next_link value isn't valid
-            assert_valid_next_link(self.hs, next_link)
+            assert_valid_next_link(self.hs, body.next_link)
 
         await self.identity_handler.ratelimit_request_token_requests(
-            request, "email", email
+            request, "email", body.email
         )
 
         # The email will be sent to the stored address.
@@ -113,7 +101,7 @@ class EmailPasswordRequestTokenRestServlet(RestServlet):
         # an email address which is controlled by the attacker but which, after
         # canonicalisation, matches the one in our database.
         existing_user_id = await self.hs.get_datastores().main.get_user_id_by_threepid(
-            "email", email
+            "email", body.email
         )
 
         if existing_user_id is None:
@@ -129,15 +117,14 @@ class EmailPasswordRequestTokenRestServlet(RestServlet):
 
         # Send password reset emails from Synapse
         sid = await self.identity_handler.send_threepid_validation(
-            email,
-            client_secret,
-            send_attempt,
+            body.email,
+            body.client_secret,
+            body.send_attempt,
             self.mailer.send_password_reset_mail,
-            next_link,
+            body.next_link,
         )
-
         threepid_send_requests.labels(type="email", reason="password_reset").observe(
-            send_attempt
+            body.send_attempt
         )
 
         # Wrap the session id in a JSON object
@@ -156,16 +143,23 @@ class PasswordRestServlet(RestServlet):
         self.password_policy_handler = hs.get_password_policy_handler()
         self._set_password_handler = hs.get_set_password_handler()
 
+    class PostBody(RequestBodyModel):
+        auth: Optional[AuthenticationData] = None
+        logout_devices: StrictBool = True
+        if TYPE_CHECKING:
+            # workaround for https://github.com/samuelcolvin/pydantic/issues/156
+            new_password: Optional[StrictStr] = None
+        else:
+            new_password: Optional[constr(max_length=512, strict=True)] = None
+
     @interactive_auth_handler
     async def on_POST(self, request: SynapseRequest) -> Tuple[int, JsonDict]:
-        body = parse_json_object_from_request(request)
+        body = parse_and_validate_json_object_from_request(request, self.PostBody)
 
         # we do basic sanity checks here because the auth layer will store these
         # in sessions. Pull out the new password provided to us.
-        new_password = body.pop("new_password", None)
+        new_password = body.new_password
         if new_password is not None:
-            if not isinstance(new_password, str) or len(new_password) > 512:
-                raise SynapseError(400, "Invalid password")
             self.password_policy_handler.validate_password(new_password)
 
         # there are two possibilities here. Either the user does not have an
@@ -185,7 +179,7 @@ class PasswordRestServlet(RestServlet):
                 params, session_id = await self.auth_handler.validate_user_via_ui_auth(
                     requester,
                     request,
-                    body,
+                    body.dict(exclude_unset=True),
                     "modify your account password",
                 )
             except InteractiveAuthIncompleteError as e:
@@ -208,7 +202,7 @@ class PasswordRestServlet(RestServlet):
                 result, params, session_id = await self.auth_handler.check_ui_auth(
                     [[LoginType.EMAIL_IDENTITY]],
                     request,
-                    body,
+                    body.dict(exclude_unset=True),
                     "modify your account password",
                 )
             except InteractiveAuthIncompleteError as e:
@@ -283,37 +277,33 @@ class DeactivateAccountRestServlet(RestServlet):
         self.auth_handler = hs.get_auth_handler()
         self._deactivate_account_handler = hs.get_deactivate_account_handler()
 
+    class PostBody(RequestBodyModel):
+        auth: Optional[AuthenticationData] = None
+        id_server: Optional[StrictStr] = None
+        # Not specced, see https://github.com/matrix-org/matrix-spec/issues/297
+        erase: StrictBool = False
+
     @interactive_auth_handler
     async def on_POST(self, request: SynapseRequest) -> Tuple[int, JsonDict]:
-        body = parse_json_object_from_request(request)
-        erase = body.get("erase", False)
-        if not isinstance(erase, bool):
-            raise SynapseError(
-                HTTPStatus.BAD_REQUEST,
-                "Param 'erase' must be a boolean, if given",
-                Codes.BAD_JSON,
-            )
+        body = parse_and_validate_json_object_from_request(request, self.PostBody)
 
         requester = await self.auth.get_user_by_req(request)
 
         # allow ASes to deactivate their own users
         if requester.app_service:
             await self._deactivate_account_handler.deactivate_account(
-                requester.user.to_string(), erase, requester
+                requester.user.to_string(), body.erase, requester
             )
             return 200, {}
 
         await self.auth_handler.validate_user_via_ui_auth(
             requester,
             request,
-            body,
+            body.dict(exclude_unset=True),
             "deactivate your account",
         )
         result = await self._deactivate_account_handler.deactivate_account(
-            requester.user.to_string(),
-            erase,
-            requester,
-            id_server=body.get("id_server"),
+            requester.user.to_string(), body.erase, requester, id_server=body.id_server
         )
         if result:
             id_server_unbind_result = "success"
@@ -347,28 +337,15 @@ class EmailThreepidRequestTokenRestServlet(RestServlet):
                 "Adding emails have been disabled due to lack of an email config"
             )
             raise SynapseError(
-                400, "Adding an email to your account is disabled on this server"
+                400,
+                "Adding an email to your account is disabled on this server",
             )
 
-        body = parse_json_object_from_request(request)
-        assert_params_in_dict(body, ["client_secret", "email", "send_attempt"])
-        client_secret = body["client_secret"]
-        assert_valid_client_secret(client_secret)
-
-        # Canonicalise the email address. The addresses are all stored canonicalised
-        # in the database.
-        # This ensures that the validation email is sent to the canonicalised address
-        # as it will later be entered into the database.
-        # Otherwise the email will be sent to "FOO@bar.com" and stored as
-        # "foo@bar.com" in database.
-        try:
-            email = validate_email(body["email"])
-        except ValueError as e:
-            raise SynapseError(400, str(e))
-        send_attempt = body["send_attempt"]
-        next_link = body.get("next_link")  # Optional param
+        body = parse_and_validate_json_object_from_request(
+            request, EmailRequestTokenBody
+        )
 
-        if not await check_3pid_allowed(self.hs, "email", email):
+        if not await check_3pid_allowed(self.hs, "email", body.email):
             raise SynapseError(
                 403,
                 "Your email domain is not authorized on this server",
@@ -376,14 +353,14 @@ class EmailThreepidRequestTokenRestServlet(RestServlet):
             )
 
         await self.identity_handler.ratelimit_request_token_requests(
-            request, "email", email
+            request, "email", body.email
         )
 
-        if next_link:
+        if body.next_link:
             # Raise if the provided next_link value isn't valid
-            assert_valid_next_link(self.hs, next_link)
+            assert_valid_next_link(self.hs, body.next_link)
 
-        existing_user_id = await self.store.get_user_id_by_threepid("email", email)
+        existing_user_id = await self.store.get_user_id_by_threepid("email", body.email)
 
         if existing_user_id is not None:
             if self.config.server.request_token_inhibit_3pid_errors:
@@ -396,16 +373,17 @@ class EmailThreepidRequestTokenRestServlet(RestServlet):
 
             raise SynapseError(400, "Email is already in use", Codes.THREEPID_IN_USE)
 
+        # Send threepid validation emails from Synapse
         sid = await self.identity_handler.send_threepid_validation(
-            email,
-            client_secret,
-            send_attempt,
+            body.email,
+            body.client_secret,
+            body.send_attempt,
             self.mailer.send_add_threepid_mail,
-            next_link,
+            body.next_link,
         )
 
         threepid_send_requests.labels(type="email", reason="add_threepid").observe(
-            send_attempt
+            body.send_attempt
         )
 
         # Wrap the session id in a JSON object
diff --git a/synapse/rest/client/devices.py b/synapse/rest/client/devices.py
index 6fab102437..ed6ce78d47 100644
--- a/synapse/rest/client/devices.py
+++ b/synapse/rest/client/devices.py
@@ -42,12 +42,26 @@ class DevicesRestServlet(RestServlet):
         self.hs = hs
         self.auth = hs.get_auth()
         self.device_handler = hs.get_device_handler()
+        self._msc3852_enabled = hs.config.experimental.msc3852_enabled
 
     async def on_GET(self, request: SynapseRequest) -> Tuple[int, JsonDict]:
         requester = await self.auth.get_user_by_req(request, allow_guest=True)
         devices = await self.device_handler.get_devices_by_user(
             requester.user.to_string()
         )
+
+        # If MSC3852 is disabled, then the "last_seen_user_agent" field will be
+        # removed from each device. If it is enabled, then the field name will
+        # be replaced by the unstable identifier.
+        #
+        # When MSC3852 is accepted, this block of code can just be removed to
+        # expose "last_seen_user_agent" to clients.
+        for device in devices:
+            last_seen_user_agent = device["last_seen_user_agent"]
+            del device["last_seen_user_agent"]
+            if self._msc3852_enabled:
+                device["org.matrix.msc3852.last_seen_user_agent"] = last_seen_user_agent
+
         return 200, {"devices": devices}
 
 
@@ -108,6 +122,7 @@ class DeviceRestServlet(RestServlet):
         self.auth = hs.get_auth()
         self.device_handler = hs.get_device_handler()
         self.auth_handler = hs.get_auth_handler()
+        self._msc3852_enabled = hs.config.experimental.msc3852_enabled
 
     async def on_GET(
         self, request: SynapseRequest, device_id: str
@@ -118,6 +133,18 @@ class DeviceRestServlet(RestServlet):
         )
         if device is None:
             raise NotFoundError("No device found")
+
+        # If MSC3852 is disabled, then the "last_seen_user_agent" field will be
+        # removed from each device. If it is enabled, then the field name will
+        # be replaced by the unstable identifier.
+        #
+        # When MSC3852 is accepted, this block of code can just be removed to
+        # expose "last_seen_user_agent" to clients.
+        last_seen_user_agent = device["last_seen_user_agent"]
+        del device["last_seen_user_agent"]
+        if self._msc3852_enabled:
+            device["org.matrix.msc3852.last_seen_user_agent"] = last_seen_user_agent
+
         return 200, device
 
     @interactive_auth_handler
diff --git a/synapse/rest/client/keys.py b/synapse/rest/client/keys.py
index eb1b85721f..a395694fa5 100644
--- a/synapse/rest/client/keys.py
+++ b/synapse/rest/client/keys.py
@@ -26,7 +26,7 @@ from synapse.http.servlet import (
     parse_string,
 )
 from synapse.http.site import SynapseRequest
-from synapse.logging.opentracing import log_kv, set_tag, trace_with_opname
+from synapse.logging.opentracing import log_kv, set_tag
 from synapse.types import JsonDict, StreamToken
 
 from ._base import client_patterns, interactive_auth_handler
@@ -71,7 +71,6 @@ class KeyUploadServlet(RestServlet):
         self.e2e_keys_handler = hs.get_e2e_keys_handler()
         self.device_handler = hs.get_device_handler()
 
-    @trace_with_opname("upload_keys")
     async def on_POST(
         self, request: SynapseRequest, device_id: Optional[str]
     ) -> Tuple[int, JsonDict]:
@@ -208,7 +207,9 @@ class KeyChangesServlet(RestServlet):
 
         # We want to enforce they do pass us one, but we ignore it and return
         # changes after the "to" as well as before.
-        set_tag("to", parse_string(request, "to"))
+        #
+        # XXX This does not enforce that "to" is passed.
+        set_tag("to", str(parse_string(request, "to")))
 
         from_token = await StreamToken.from_string(self.store, from_token_string)
 
diff --git a/synapse/rest/client/models.py b/synapse/rest/client/models.py
new file mode 100644
index 0000000000..3150602997
--- /dev/null
+++ b/synapse/rest/client/models.py
@@ -0,0 +1,69 @@
+# Copyright 2022 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from typing import TYPE_CHECKING, Dict, Optional
+
+from pydantic import Extra, StrictInt, StrictStr, constr, validator
+
+from synapse.rest.models import RequestBodyModel
+from synapse.util.threepids import validate_email
+
+
+class AuthenticationData(RequestBodyModel):
+    """
+    Data used during user-interactive authentication.
+
+    (The name "Authentication Data" is taken directly from the spec.)
+
+    Additional keys will be present, depending on the `type` field. Use `.dict()` to
+    access them.
+    """
+
+    class Config:
+        extra = Extra.allow
+
+    session: Optional[StrictStr] = None
+    type: Optional[StrictStr] = None
+
+
+class EmailRequestTokenBody(RequestBodyModel):
+    if TYPE_CHECKING:
+        client_secret: StrictStr
+    else:
+        # See also assert_valid_client_secret()
+        client_secret: constr(
+            regex="[0-9a-zA-Z.=_-]",  # noqa: F722
+            min_length=0,
+            max_length=255,
+            strict=True,
+        )
+    email: StrictStr
+    id_server: Optional[StrictStr]
+    id_access_token: Optional[StrictStr]
+    next_link: Optional[StrictStr]
+    send_attempt: StrictInt
+
+    @validator("id_access_token", always=True)
+    def token_required_for_identity_server(
+        cls, token: Optional[str], values: Dict[str, object]
+    ) -> Optional[str]:
+        if values.get("id_server") is not None and token is None:
+            raise ValueError("id_access_token is required if an id_server is supplied.")
+        return token
+
+    # Canonicalise the email address. The addresses are all stored canonicalised
+    # in the database. This allows the user to reset his password without having to
+    # know the exact spelling (eg. upper and lower case) of address in the database.
+    # Without this, an email stored in the database as "foo@bar.com" would cause
+    # user requests for "FOO@bar.com" to raise a Not Found error.
+    _email_validator = validator("email", allow_reuse=True)(validate_email)
diff --git a/synapse/rest/client/notifications.py b/synapse/rest/client/notifications.py
index 24bc7c9095..a73322a6a4 100644
--- a/synapse/rest/client/notifications.py
+++ b/synapse/rest/client/notifications.py
@@ -58,7 +58,12 @@ class NotificationsServlet(RestServlet):
         )
 
         receipts_by_room = await self.store.get_receipts_for_user_with_orderings(
-            user_id, [ReceiptTypes.READ, ReceiptTypes.READ_PRIVATE]
+            user_id,
+            [
+                ReceiptTypes.READ,
+                ReceiptTypes.READ_PRIVATE,
+                ReceiptTypes.UNSTABLE_READ_PRIVATE,
+            ],
         )
 
         notif_event_ids = [pa.event_id for pa in push_actions]
diff --git a/synapse/rest/client/profile.py b/synapse/rest/client/profile.py
index c16d707909..e69fa0829d 100644
--- a/synapse/rest/client/profile.py
+++ b/synapse/rest/client/profile.py
@@ -66,7 +66,7 @@ class ProfileDisplaynameRestServlet(RestServlet):
     ) -> Tuple[int, JsonDict]:
         requester = await self.auth.get_user_by_req(request, allow_guest=True)
         user = UserID.from_string(user_id)
-        is_admin = await self.auth.is_server_admin(requester.user)
+        is_admin = await self.auth.is_server_admin(requester)
 
         content = parse_json_object_from_request(request)
 
@@ -123,7 +123,7 @@ class ProfileAvatarURLRestServlet(RestServlet):
     ) -> Tuple[int, JsonDict]:
         requester = await self.auth.get_user_by_req(request)
         user = UserID.from_string(user_id)
-        is_admin = await self.auth.is_server_admin(requester.user)
+        is_admin = await self.auth.is_server_admin(requester)
 
         content = parse_json_object_from_request(request)
         try:
diff --git a/synapse/rest/client/read_marker.py b/synapse/rest/client/read_marker.py
index 8896f2df50..aaad8b233f 100644
--- a/synapse/rest/client/read_marker.py
+++ b/synapse/rest/client/read_marker.py
@@ -40,9 +40,13 @@ class ReadMarkerRestServlet(RestServlet):
         self.read_marker_handler = hs.get_read_marker_handler()
         self.presence_handler = hs.get_presence_handler()
 
-        self._known_receipt_types = {ReceiptTypes.READ, ReceiptTypes.FULLY_READ}
+        self._known_receipt_types = {
+            ReceiptTypes.READ,
+            ReceiptTypes.FULLY_READ,
+            ReceiptTypes.READ_PRIVATE,
+        }
         if hs.config.experimental.msc2285_enabled:
-            self._known_receipt_types.add(ReceiptTypes.READ_PRIVATE)
+            self._known_receipt_types.add(ReceiptTypes.UNSTABLE_READ_PRIVATE)
 
     async def on_POST(
         self, request: SynapseRequest, room_id: str
diff --git a/synapse/rest/client/receipts.py b/synapse/rest/client/receipts.py
index 409bfd43c1..c6108fc5eb 100644
--- a/synapse/rest/client/receipts.py
+++ b/synapse/rest/client/receipts.py
@@ -44,11 +44,13 @@ class ReceiptRestServlet(RestServlet):
         self.read_marker_handler = hs.get_read_marker_handler()
         self.presence_handler = hs.get_presence_handler()
 
-        self._known_receipt_types = {ReceiptTypes.READ}
+        self._known_receipt_types = {
+            ReceiptTypes.READ,
+            ReceiptTypes.READ_PRIVATE,
+            ReceiptTypes.FULLY_READ,
+        }
         if hs.config.experimental.msc2285_enabled:
-            self._known_receipt_types.update(
-                (ReceiptTypes.READ_PRIVATE, ReceiptTypes.FULLY_READ)
-            )
+            self._known_receipt_types.add(ReceiptTypes.UNSTABLE_READ_PRIVATE)
 
     async def on_POST(
         self, request: SynapseRequest, room_id: str, receipt_type: str, event_id: str
diff --git a/synapse/rest/client/register.py b/synapse/rest/client/register.py
index a8402cdb3a..20bab20c8f 100644
--- a/synapse/rest/client/register.py
+++ b/synapse/rest/client/register.py
@@ -32,7 +32,7 @@ from synapse.api.errors import (
 from synapse.api.ratelimiting import Ratelimiter
 from synapse.config import ConfigError
 from synapse.config.homeserver import HomeServerConfig
-from synapse.config.ratelimiting import FederationRateLimitConfig
+from synapse.config.ratelimiting import FederationRatelimitSettings
 from synapse.config.server import is_threepid_reserved
 from synapse.handlers.auth import AuthHandler
 from synapse.handlers.ui_auth import UIAuthSessionDataConstants
@@ -306,7 +306,7 @@ class UsernameAvailabilityRestServlet(RestServlet):
         self.registration_handler = hs.get_registration_handler()
         self.ratelimiter = FederationRateLimiter(
             hs.get_clock(),
-            FederationRateLimitConfig(
+            FederationRatelimitSettings(
                 # Time window of 2s
                 window_size=2000,
                 # Artificially delay requests if rate > sleep_limit/window_size
@@ -465,9 +465,6 @@ class RegisterRestServlet(RestServlet):
                     "Appservice token must be provided when using a type of m.login.application_service",
                 )
 
-            # Verify the AS
-            self.auth.get_appservice_by_req(request)
-
             # Set the desired user according to the AS API (which uses the
             # 'user' key not 'username'). Since this is a new addition, we'll
             # fallback to 'username' if they gave one.
diff --git a/synapse/rest/client/room.py b/synapse/rest/client/room.py
index 2f513164cb..3259de4802 100644
--- a/synapse/rest/client/room.py
+++ b/synapse/rest/client/room.py
@@ -16,9 +16,12 @@
 """ This module contains REST servlets to do with rooms: /rooms/<paths> """
 import logging
 import re
+from enum import Enum
 from typing import TYPE_CHECKING, Awaitable, Dict, List, Optional, Tuple
 from urllib import parse as urlparse
 
+from prometheus_client.core import Histogram
+
 from twisted.web.server import Request
 
 from synapse import event_auth
@@ -46,6 +49,7 @@ from synapse.http.servlet import (
     parse_strings_from_args,
 )
 from synapse.http.site import SynapseRequest
+from synapse.logging.context import make_deferred_yieldable, run_in_background
 from synapse.logging.opentracing import set_tag
 from synapse.rest.client._base import client_patterns
 from synapse.rest.client.transactions import HttpTransactionCache
@@ -61,6 +65,70 @@ if TYPE_CHECKING:
 logger = logging.getLogger(__name__)
 
 
+class _RoomSize(Enum):
+    """
+    Enum to differentiate sizes of rooms. This is a pretty good approximation
+    about how hard it will be to get events in the room. We could also look at
+    room "complexity".
+    """
+
+    # This doesn't necessarily mean the room is a DM, just that there is a DM
+    # amount of people there.
+    DM_SIZE = "direct_message_size"
+    SMALL = "small"
+    SUBSTANTIAL = "substantial"
+    LARGE = "large"
+
+    @staticmethod
+    def from_member_count(member_count: int) -> "_RoomSize":
+        if member_count <= 2:
+            return _RoomSize.DM_SIZE
+        elif member_count < 100:
+            return _RoomSize.SMALL
+        elif member_count < 1000:
+            return _RoomSize.SUBSTANTIAL
+        else:
+            return _RoomSize.LARGE
+
+
+# This is an extra metric on top of `synapse_http_server_response_time_seconds`
+# which times the same sort of thing but this one allows us to see values
+# greater than 10s. We use a separate dedicated histogram with its own buckets
+# so that we don't increase the cardinality of the general one because it's
+# multiplied across hundreds of servlets.
+messsages_response_timer = Histogram(
+    "synapse_room_message_list_rest_servlet_response_time_seconds",
+    "sec",
+    # We have a label for room size so we can try to see a more realistic
+    # picture of /messages response time for bigger rooms. We don't want the
+    # tiny rooms that can always respond fast skewing our results when we're trying
+    # to optimize the bigger cases.
+    ["room_size"],
+    buckets=(
+        0.005,
+        0.01,
+        0.025,
+        0.05,
+        0.1,
+        0.25,
+        0.5,
+        1.0,
+        2.5,
+        5.0,
+        10.0,
+        20.0,
+        30.0,
+        60.0,
+        80.0,
+        100.0,
+        120.0,
+        150.0,
+        180.0,
+        "+Inf",
+    ),
+)
+
+
 class TransactionRestServlet(RestServlet):
     def __init__(self, hs: "HomeServer"):
         super().__init__()
@@ -165,7 +233,7 @@ class RoomStateEventRestServlet(TransactionRestServlet):
 
         msg_handler = self.message_handler
         data = await msg_handler.get_room_data(
-            user_id=requester.user.to_string(),
+            requester=requester,
             room_id=room_id,
             event_type=event_type,
             state_key=state_key,
@@ -510,7 +578,7 @@ class RoomMemberListRestServlet(RestServlet):
 
         events = await handler.get_state_events(
             room_id=room_id,
-            user_id=requester.user.to_string(),
+            requester=requester,
             at_token=at_token,
             state_filter=StateFilter.from_types([(EventTypes.Member, None)]),
         )
@@ -556,6 +624,7 @@ class RoomMessageListRestServlet(RestServlet):
     def __init__(self, hs: "HomeServer"):
         super().__init__()
         self._hs = hs
+        self.clock = hs.get_clock()
         self.pagination_handler = hs.get_pagination_handler()
         self.auth = hs.get_auth()
         self.store = hs.get_datastores().main
@@ -563,6 +632,18 @@ class RoomMessageListRestServlet(RestServlet):
     async def on_GET(
         self, request: SynapseRequest, room_id: str
     ) -> Tuple[int, JsonDict]:
+        processing_start_time = self.clock.time_msec()
+        # Fire off and hope that we get a result by the end.
+        #
+        # We're using the mypy type ignore comment because the `@cached`
+        # decorator on `get_number_joined_users_in_room` doesn't play well with
+        # the type system. Maybe in the future, it can use some ParamSpec
+        # wizardry to fix it up.
+        room_member_count_deferred = run_in_background(  # type: ignore[call-arg]
+            self.store.get_number_joined_users_in_room,
+            room_id,  # type: ignore[arg-type]
+        )
+
         requester = await self.auth.get_user_by_req(request, allow_guest=True)
         pagination_config = await PaginationConfig.from_request(
             self.store, request, default_limit=10
@@ -593,6 +674,12 @@ class RoomMessageListRestServlet(RestServlet):
             event_filter=event_filter,
         )
 
+        processing_end_time = self.clock.time_msec()
+        room_member_count = await make_deferred_yieldable(room_member_count_deferred)
+        messsages_response_timer.labels(
+            room_size=_RoomSize.from_member_count(room_member_count)
+        ).observe((processing_end_time - processing_start_time) / 1000)
+
         return 200, msgs
 
 
@@ -613,8 +700,7 @@ class RoomStateRestServlet(RestServlet):
         # Get all the current state for this room
         events = await self.message_handler.get_state_events(
             room_id=room_id,
-            user_id=requester.user.to_string(),
-            is_guest=requester.is_guest,
+            requester=requester,
         )
         return 200, events
 
@@ -672,7 +758,7 @@ class RoomEventServlet(RestServlet):
             == "true"
         )
         if include_unredacted_content and not await self.auth.is_server_admin(
-            requester.user
+            requester
         ):
             power_level_event = (
                 await self._storage_controllers.state.get_current_state_event(
@@ -1177,9 +1263,7 @@ class TimestampLookupRestServlet(RestServlet):
         self, request: SynapseRequest, room_id: str
     ) -> Tuple[int, JsonDict]:
         requester = await self._auth.get_user_by_req(request)
-        await self._auth.check_user_in_room_or_world_readable(
-            room_id, requester.user.to_string()
-        )
+        await self._auth.check_user_in_room_or_world_readable(room_id, requester)
 
         timestamp = parse_integer(request, "ts", required=True)
         direction = parse_string(request, "dir", default="f", allowed_values=["f", "b"])
diff --git a/synapse/rest/client/sendtodevice.py b/synapse/rest/client/sendtodevice.py
index 1a8e9a96d4..46a8b03829 100644
--- a/synapse/rest/client/sendtodevice.py
+++ b/synapse/rest/client/sendtodevice.py
@@ -19,7 +19,7 @@ from synapse.http import servlet
 from synapse.http.server import HttpServer
 from synapse.http.servlet import assert_params_in_dict, parse_json_object_from_request
 from synapse.http.site import SynapseRequest
-from synapse.logging.opentracing import set_tag, trace_with_opname
+from synapse.logging.opentracing import set_tag
 from synapse.rest.client.transactions import HttpTransactionCache
 from synapse.types import JsonDict
 
@@ -43,7 +43,6 @@ class SendToDeviceRestServlet(servlet.RestServlet):
         self.txns = HttpTransactionCache(hs)
         self.device_message_handler = hs.get_device_message_handler()
 
-    @trace_with_opname("sendToDevice")
     def on_PUT(
         self, request: SynapseRequest, message_type: str, txn_id: str
     ) -> Awaitable[Tuple[int, JsonDict]]:
diff --git a/synapse/rest/client/versions.py b/synapse/rest/client/versions.py
index f4f06563dd..c9a830cbac 100644
--- a/synapse/rest/client/versions.py
+++ b/synapse/rest/client/versions.py
@@ -94,9 +94,10 @@ class VersionsRestServlet(RestServlet):
                     # Supports the busy presence state described in MSC3026.
                     "org.matrix.msc3026.busy_presence": self.config.experimental.msc3026_enabled,
                     # Supports receiving private read receipts as per MSC2285
+                    "org.matrix.msc2285.stable": True,  # TODO: Remove when MSC2285 becomes a part of the spec
                     "org.matrix.msc2285": self.config.experimental.msc2285_enabled,
-                    # Supports filtering of /publicRooms by room type MSC3827
-                    "org.matrix.msc3827": self.config.experimental.msc3827_enabled,
+                    # Supports filtering of /publicRooms by room type as per MSC3827
+                    "org.matrix.msc3827.stable": True,
                     # Adds support for importing historical messages as per MSC2716
                     "org.matrix.msc2716": self.config.experimental.msc2716_enabled,
                     # Adds support for jump to date endpoints (/timestamp_to_event) as per MSC3030
diff --git a/synapse/rest/models.py b/synapse/rest/models.py
new file mode 100644
index 0000000000..ac39cda8e5
--- /dev/null
+++ b/synapse/rest/models.py
@@ -0,0 +1,23 @@
+from pydantic import BaseModel, Extra
+
+
+class RequestBodyModel(BaseModel):
+    """A custom version of Pydantic's BaseModel which
+
+     - ignores unknown fields and
+     - does not allow fields to be overwritten after construction,
+
+    but otherwise uses Pydantic's default behaviour.
+
+    Ignoring unknown fields is a useful default. It means that clients can provide
+    unstable field not known to the server without the request being refused outright.
+
+    Subclassing in this way is recommended by
+    https://pydantic-docs.helpmanual.io/usage/model_config/#change-behaviour-globally
+    """
+
+    class Config:
+        # By default, ignore fields that we don't recognise.
+        extra = Extra.ignore
+        # By default, don't allow fields to be reassigned after parsing.
+        allow_mutation = False
diff --git a/synapse/server_notices/server_notices_manager.py b/synapse/server_notices/server_notices_manager.py
index 8ecab86ec7..70d054a8f4 100644
--- a/synapse/server_notices/server_notices_manager.py
+++ b/synapse/server_notices/server_notices_manager.py
@@ -244,7 +244,7 @@ class ServerNoticesManager:
         assert self.server_notices_mxid is not None
 
         notice_user_data_in_room = await self._message_handler.get_room_data(
-            self.server_notices_mxid,
+            create_requester(self.server_notices_mxid),
             room_id,
             EventTypes.Member,
             self.server_notices_mxid,
diff --git a/synapse/state/__init__.py b/synapse/state/__init__.py
index e3faa52cd6..3047e1b1ad 100644
--- a/synapse/state/__init__.py
+++ b/synapse/state/__init__.py
@@ -14,7 +14,7 @@
 # limitations under the License.
 import heapq
 import logging
-from collections import defaultdict
+from collections import ChainMap, defaultdict
 from typing import (
     TYPE_CHECKING,
     Any,
@@ -44,7 +44,6 @@ from synapse.logging.context import ContextResourceUsage
 from synapse.replication.http.state import ReplicationUpdateCurrentStateRestServlet
 from synapse.state import v1, v2
 from synapse.storage.databases.main.events_worker import EventRedactBehaviour
-from synapse.storage.roommember import ProfileInfo
 from synapse.storage.state import StateFilter
 from synapse.types import StateMap
 from synapse.util.async_helpers import Linearizer
@@ -92,8 +91,11 @@ class _StateCacheEntry:
         prev_group: Optional[int] = None,
         delta_ids: Optional[StateMap[str]] = None,
     ):
-        if state is None and state_group is None:
-            raise Exception("Either state or state group must be not None")
+        if state is None and state_group is None and prev_group is None:
+            raise Exception("One of state, state_group or prev_group must be not None")
+
+        if prev_group is not None and delta_ids is None:
+            raise Exception("If prev_group is set so must delta_ids")
 
         # A map from (type, state_key) to event_id.
         #
@@ -120,18 +122,48 @@ class _StateCacheEntry:
         if self._state is not None:
             return self._state
 
-        assert self.state_group is not None
+        if self.state_group is not None:
+            return await state_storage.get_state_ids_for_group(
+                self.state_group, state_filter
+            )
+
+        assert self.prev_group is not None and self.delta_ids is not None
 
-        return await state_storage.get_state_ids_for_group(
-            self.state_group, state_filter
+        prev_state = await state_storage.get_state_ids_for_group(
+            self.prev_group, state_filter
         )
 
+        # ChainMap expects MutableMapping, but since we're using it immutably
+        # its safe to give it immutable maps.
+        return ChainMap(self.delta_ids, prev_state)  # type: ignore[arg-type]
+
+    def set_state_group(self, state_group: int) -> None:
+        """Update the state group assigned to this state (e.g. after we've
+        persisted it).
+
+        Note: this will cause the cache entry to drop any stored state.
+        """
+
+        self.state_group = state_group
+
+        # We clear out the state as we know longer need to explicitly keep it in
+        # the `state_cache` (as the store state group cache will do that).
+        self._state = None
+
     def __len__(self) -> int:
-        # The len should is used to estimate how large this cache entry is, for
-        # cache eviction purposes. This is why if `self.state` is None it's fine
-        # to return 1.
+        # The len should be used to estimate how large this cache entry is, for
+        # cache eviction purposes. This is why it's fine to return 1 if we're
+        # not storing any state.
+
+        length = 0
+
+        if self._state:
+            length += len(self._state)
 
-        return len(self._state) if self._state else 1
+        if self.delta_ids:
+            length += len(self.delta_ids)
+
+        return length or 1  # Make sure its not 0.
 
 
 class StateHandler:
@@ -177,11 +209,11 @@ class StateHandler:
         ret = await self.resolve_state_groups_for_events(room_id, event_ids)
         return await ret.get_state(self._state_storage_controller, state_filter)
 
-    async def get_current_users_in_room(
+    async def get_current_user_ids_in_room(
         self, room_id: str, latest_event_ids: List[str]
-    ) -> Dict[str, ProfileInfo]:
+    ) -> Set[str]:
         """
-        Get the users who are currently in a room.
+        Get the users IDs who are currently in a room.
 
         Note: This is much slower than using the equivalent method
         `DataStore.get_users_in_room` or `DataStore.get_users_in_room_with_profiles`,
@@ -192,15 +224,15 @@ class StateHandler:
             room_id: The ID of the room.
             latest_event_ids: Precomputed list of latest event IDs. Will be computed if None.
         Returns:
-            Dictionary of user IDs to their profileinfo.
+            Set of user IDs in the room.
         """
 
         assert latest_event_ids is not None
 
-        logger.debug("calling resolve_state_groups from get_current_users_in_room")
+        logger.debug("calling resolve_state_groups from get_current_user_ids_in_room")
         entry = await self.resolve_state_groups_for_events(room_id, latest_event_ids)
         state = await entry.get_state(self._state_storage_controller, StateFilter.all())
-        return await self.store.get_joined_users_from_state(room_id, state, entry)
+        return await self.store.get_joined_user_ids_from_state(room_id, state, entry)
 
     async def get_hosts_in_room_at_events(
         self, room_id: str, event_ids: Collection[str]
@@ -222,7 +254,7 @@ class StateHandler:
         self,
         event: EventBase,
         state_ids_before_event: Optional[StateMap[str]] = None,
-        partial_state: bool = False,
+        partial_state: Optional[bool] = None,
     ) -> EventContext:
         """Build an EventContext structure for a non-outlier event.
 
@@ -237,10 +269,18 @@ class StateHandler:
                 it can't be calculated from existing events. This is normally
                 only specified when receiving an event from federation where we
                 don't have the prev events, e.g. when backfilling.
-            partial_state: True if `state_ids_before_event` is partial and omits
-                non-critical membership events
+            partial_state:
+                `True` if `state_ids_before_event` is partial and omits non-critical
+                membership events.
+                `False` if `state_ids_before_event` is the full state.
+                `None` when `state_ids_before_event` is not provided. In this case, the
+                flag will be calculated based on `event`'s prev events.
         Returns:
             The event context.
+
+        Raises:
+            RuntimeError if `state_ids_before_event` is not provided and one or more
+                prev events are missing or outliers.
         """
 
         assert not event.internal_metadata.is_outlier()
@@ -265,12 +305,14 @@ class StateHandler:
                 )
             )
 
+            # the partial_state flag must be provided
+            assert partial_state is not None
         else:
             # otherwise, we'll need to resolve the state across the prev_events.
 
             # partial_state should not be set explicitly in this case:
             # we work it out dynamically
-            assert not partial_state
+            assert partial_state is None
 
             # if any of the prev-events have partial state, so do we.
             # (This is slightly racy - the prev-events might get fixed up before we use
@@ -280,13 +322,13 @@ class StateHandler:
             incomplete_prev_events = await self.store.get_partial_state_events(
                 prev_event_ids
             )
-            if any(incomplete_prev_events.values()):
+            partial_state = any(incomplete_prev_events.values())
+            if partial_state:
                 logger.debug(
                     "New/incoming event %s refers to prev_events %s with partial state",
                     event.event_id,
                     [k for (k, v) in incomplete_prev_events.items() if v],
                 )
-                partial_state = True
 
             logger.debug("calling resolve_state_groups from compute_event_context")
             # we've already taken into account partial state, so no need to wait for
@@ -320,7 +362,7 @@ class StateHandler:
                         current_state_ids=state_ids_before_event,
                     )
                 )
-                entry.state_group = state_group_before_event
+                entry.set_state_group(state_group_before_event)
             else:
                 state_group_before_event = entry.state_group
 
@@ -393,6 +435,10 @@ class StateHandler:
 
         Returns:
             The resolved state
+
+        Raises:
+            RuntimeError if we don't have a state group for one or more of the events
+               (ie. they are outliers or unknown)
         """
         logger.debug("resolve_state_groups event_ids %s", event_ids)
 
@@ -747,7 +793,7 @@ def _make_state_cache_entry(
         old_state_event_ids = set(state.values())
         if new_state_event_ids == old_state_event_ids:
             # got an exact match.
-            return _StateCacheEntry(state=new_state, state_group=sg)
+            return _StateCacheEntry(state=None, state_group=sg)
 
     # TODO: We want to create a state group for this set of events, to
     # increase cache hits, but we need to make sure that it doesn't
@@ -769,9 +815,14 @@ def _make_state_cache_entry(
             prev_group = old_group
             delta_ids = n_delta_ids
 
-    return _StateCacheEntry(
-        state=new_state, state_group=None, prev_group=prev_group, delta_ids=delta_ids
-    )
+    if prev_group is not None:
+        # If we have a prev group and deltas then we can drop the new state from
+        # the cache (to reduce memory usage).
+        return _StateCacheEntry(
+            state=None, state_group=None, prev_group=prev_group, delta_ids=delta_ids
+        )
+    else:
+        return _StateCacheEntry(state=new_state, state_group=None)
 
 
 @attr.s(slots=True, auto_attribs=True)
diff --git a/synapse/state/v2.py b/synapse/state/v2.py
index 7db032203b..cf3045f82e 100644
--- a/synapse/state/v2.py
+++ b/synapse/state/v2.py
@@ -434,7 +434,7 @@ async def _add_event_and_auth_chain_to_graph(
     event_id: str,
     event_map: Dict[str, EventBase],
     state_res_store: StateResolutionStore,
-    auth_diff: Set[str],
+    full_conflicted_set: Set[str],
 ) -> None:
     """Helper function for _reverse_topological_power_sort that add the event
     and its auth chain (that is in the auth diff) to the graph
@@ -445,7 +445,7 @@ async def _add_event_and_auth_chain_to_graph(
         event_id: Event to add to the graph
         event_map
         state_res_store
-        auth_diff: Set of event IDs that are in the auth difference.
+        full_conflicted_set: Set of event IDs that are in the full conflicted set.
     """
 
     state = [event_id]
@@ -455,7 +455,7 @@ async def _add_event_and_auth_chain_to_graph(
 
         event = await _get_event(room_id, eid, event_map, state_res_store)
         for aid in event.auth_event_ids():
-            if aid in auth_diff:
+            if aid in full_conflicted_set:
                 if aid not in graph:
                     state.append(aid)
 
@@ -468,7 +468,7 @@ async def _reverse_topological_power_sort(
     event_ids: Iterable[str],
     event_map: Dict[str, EventBase],
     state_res_store: StateResolutionStore,
-    auth_diff: Set[str],
+    full_conflicted_set: Set[str],
 ) -> List[str]:
     """Returns a list of the event_ids sorted by reverse topological ordering,
     and then by power level and origin_server_ts
@@ -479,7 +479,7 @@ async def _reverse_topological_power_sort(
         event_ids: The events to sort
         event_map
         state_res_store
-        auth_diff: Set of event IDs that are in the auth difference.
+        full_conflicted_set: Set of event IDs that are in the full conflicted set.
 
     Returns:
         The sorted list
@@ -488,7 +488,7 @@ async def _reverse_topological_power_sort(
     graph: Dict[str, Set[str]] = {}
     for idx, event_id in enumerate(event_ids, start=1):
         await _add_event_and_auth_chain_to_graph(
-            graph, room_id, event_id, event_map, state_res_store, auth_diff
+            graph, room_id, event_id, event_map, state_res_store, full_conflicted_set
         )
 
         # We await occasionally when we're working with large data sets to
diff --git a/synapse/static/client/login/index.html b/synapse/static/client/login/index.html
index 9e6daf38ac..40510889ac 100644
--- a/synapse/static/client/login/index.html
+++ b/synapse/static/client/login/index.html
@@ -3,7 +3,8 @@
 <head>
     <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
     <title> Login </title>
-    <meta name='viewport' content='width=device-width, initial-scale=1, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0'>
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <link rel="stylesheet" href="style.css">
     <script src="js/jquery-3.4.1.min.js"></script>
     <script src="js/login.js"></script>
diff --git a/synapse/static/client/register/index.html b/synapse/static/client/register/index.html
index 140653574d..27bbd76f51 100644
--- a/synapse/static/client/register/index.html
+++ b/synapse/static/client/register/index.html
@@ -2,7 +2,8 @@
 <html>
 <head>
 <title> Registration </title>
-<meta name='viewport' content='width=device-width, initial-scale=1, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0'> 
+<meta http-equiv="X-UA-Compatible" content="IE=edge">
+<meta name="viewport" content="width=device-width, initial-scale=1.0">
 <link rel="stylesheet" href="style.css">
 <script src="js/jquery-3.4.1.min.js"></script>
 <script src="https://www.recaptcha.net/recaptcha/api/js/recaptcha_ajax.js"></script>
diff --git a/synapse/storage/_base.py b/synapse/storage/_base.py
index a2f8310388..e30f9c76d4 100644
--- a/synapse/storage/_base.py
+++ b/synapse/storage/_base.py
@@ -80,6 +80,10 @@ class SQLBaseStore(metaclass=ABCMeta):
             )
             self._attempt_to_invalidate_cache("get_local_users_in_room", (room_id,))
 
+            # There's no easy way of invalidating this cache for just the users
+            # that have changed, so we just clear the entire thing.
+            self._attempt_to_invalidate_cache("does_pair_of_users_share_a_room", None)
+
         for user_id in members_changed:
             self._attempt_to_invalidate_cache(
                 "get_user_in_room_with_profile", (room_id, user_id)
diff --git a/synapse/storage/controllers/persist_events.py b/synapse/storage/controllers/persist_events.py
index cf98b0ab48..dad3731b9b 100644
--- a/synapse/storage/controllers/persist_events.py
+++ b/synapse/storage/controllers/persist_events.py
@@ -45,8 +45,14 @@ from twisted.internet import defer
 from synapse.api.constants import EventTypes, Membership
 from synapse.events import EventBase
 from synapse.events.snapshot import EventContext
-from synapse.logging import opentracing
 from synapse.logging.context import PreserveLoggingContext, make_deferred_yieldable
+from synapse.logging.opentracing import (
+    SynapseTags,
+    active_span,
+    set_tag,
+    start_active_span_follows_from,
+    trace,
+)
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.storage.controllers.state import StateStorageController
 from synapse.storage.databases import Databases
@@ -223,7 +229,7 @@ class _EventPeristenceQueue(Generic[_PersistResult]):
             queue.append(end_item)
 
         # also add our active opentracing span to the item so that we get a link back
-        span = opentracing.active_span()
+        span = active_span()
         if span:
             end_item.parent_opentracing_span_contexts.append(span.context)
 
@@ -234,7 +240,7 @@ class _EventPeristenceQueue(Generic[_PersistResult]):
         res = await make_deferred_yieldable(end_item.deferred.observe())
 
         # add another opentracing span which links to the persist trace.
-        with opentracing.start_active_span_follows_from(
+        with start_active_span_follows_from(
             f"{task.name}_complete", (end_item.opentracing_span_context,)
         ):
             pass
@@ -266,7 +272,7 @@ class _EventPeristenceQueue(Generic[_PersistResult]):
                 queue = self._get_drainining_queue(room_id)
                 for item in queue:
                     try:
-                        with opentracing.start_active_span_follows_from(
+                        with start_active_span_follows_from(
                             item.task.name,
                             item.parent_opentracing_span_contexts,
                             inherit_force_tracing=True,
@@ -355,7 +361,7 @@ class EventsPersistenceStorageController:
                 f"Found an unexpected task type in event persistence queue: {task}"
             )
 
-    @opentracing.trace
+    @trace
     async def persist_events(
         self,
         events_and_contexts: Iterable[Tuple[EventBase, EventContext]],
@@ -380,9 +386,21 @@ class EventsPersistenceStorageController:
             PartialStateConflictError: if attempting to persist a partial state event in
                 a room that has been un-partial stated.
         """
+        event_ids: List[str] = []
         partitioned: Dict[str, List[Tuple[EventBase, EventContext]]] = {}
         for event, ctx in events_and_contexts:
             partitioned.setdefault(event.room_id, []).append((event, ctx))
+            event_ids.append(event.event_id)
+
+        set_tag(
+            SynapseTags.FUNC_ARG_PREFIX + "event_ids",
+            str(event_ids),
+        )
+        set_tag(
+            SynapseTags.FUNC_ARG_PREFIX + "event_ids.length",
+            str(len(event_ids)),
+        )
+        set_tag(SynapseTags.FUNC_ARG_PREFIX + "backfilled", str(backfilled))
 
         async def enqueue(
             item: Tuple[str, List[Tuple[EventBase, EventContext]]]
@@ -418,7 +436,7 @@ class EventsPersistenceStorageController:
             self.main_store.get_room_max_token(),
         )
 
-    @opentracing.trace
+    @trace
     async def persist_event(
         self, event: EventBase, context: EventContext, backfilled: bool = False
     ) -> Tuple[EventBase, PersistedEventPosition, RoomStreamToken]:
diff --git a/synapse/storage/controllers/state.py b/synapse/storage/controllers/state.py
index e08f956e6e..f9ffd0e29e 100644
--- a/synapse/storage/controllers/state.py
+++ b/synapse/storage/controllers/state.py
@@ -29,6 +29,8 @@ from typing import (
 
 from synapse.api.constants import EventTypes
 from synapse.events import EventBase
+from synapse.logging.opentracing import tag_args, trace
+from synapse.storage.roommember import ProfileInfo
 from synapse.storage.state import StateFilter
 from synapse.storage.util.partial_state_events_tracker import (
     PartialCurrentStateTracker,
@@ -82,13 +84,15 @@ class StateStorageController:
         return state_group_delta.prev_group, state_group_delta.delta_ids
 
     async def get_state_groups_ids(
-        self, _room_id: str, event_ids: Collection[str]
+        self, _room_id: str, event_ids: Collection[str], await_full_state: bool = True
     ) -> Dict[int, MutableStateMap[str]]:
         """Get the event IDs of all the state for the state groups for the given events
 
         Args:
             _room_id: id of the room for these events
             event_ids: ids of the events
+            await_full_state: if `True`, will block if we do not yet have complete
+               state at these events.
 
         Returns:
             dict of state_group_id -> (dict of (type, state_key) -> event id)
@@ -100,7 +104,9 @@ class StateStorageController:
         if not event_ids:
             return {}
 
-        event_to_groups = await self.get_state_group_for_events(event_ids)
+        event_to_groups = await self.get_state_group_for_events(
+            event_ids, await_full_state=await_full_state
+        )
 
         groups = set(event_to_groups.values())
         group_to_state = await self.stores.state._get_state_for_groups(groups)
@@ -175,6 +181,7 @@ class StateStorageController:
 
         return self.stores.state._get_state_groups_from_groups(groups, state_filter)
 
+    @trace
     async def get_state_for_events(
         self, event_ids: Collection[str], state_filter: Optional[StateFilter] = None
     ) -> Dict[str, StateMap[EventBase]]:
@@ -221,10 +228,13 @@ class StateStorageController:
 
         return {event: event_to_state[event] for event in event_ids}
 
+    @trace
+    @tag_args
     async def get_state_ids_for_events(
         self,
         event_ids: Collection[str],
         state_filter: Optional[StateFilter] = None,
+        await_full_state: bool = True,
     ) -> Dict[str, StateMap[str]]:
         """
         Get the state dicts corresponding to a list of events, containing the event_ids
@@ -233,6 +243,9 @@ class StateStorageController:
         Args:
             event_ids: events whose state should be returned
             state_filter: The state filter used to fetch state from the database.
+            await_full_state: if `True`, will block if we do not yet have complete state
+                at these events and `state_filter` is not satisfied by partial state.
+                Defaults to `True`.
 
         Returns:
             A dict from event_id -> (type, state_key) -> event_id
@@ -241,8 +254,12 @@ class StateStorageController:
             RuntimeError if we don't have a state group for one or more of the events
                 (ie they are outliers or unknown)
         """
-        await_full_state = True
-        if state_filter and not state_filter.must_await_full_state(self._is_mine_id):
+        if (
+            await_full_state
+            and state_filter
+            and not state_filter.must_await_full_state(self._is_mine_id)
+        ):
+            # Full state is not required if the state filter is restrictive enough.
             await_full_state = False
 
         event_to_groups = await self.get_state_group_for_events(
@@ -283,8 +300,12 @@ class StateStorageController:
         )
         return state_map[event_id]
 
+    @trace
     async def get_state_ids_for_event(
-        self, event_id: str, state_filter: Optional[StateFilter] = None
+        self,
+        event_id: str,
+        state_filter: Optional[StateFilter] = None,
+        await_full_state: bool = True,
     ) -> StateMap[str]:
         """
         Get the state dict corresponding to a particular event
@@ -292,6 +313,9 @@ class StateStorageController:
         Args:
             event_id: event whose state should be returned
             state_filter: The state filter used to fetch state from the database.
+            await_full_state: if `True`, will block if we do not yet have complete state
+                at the event and `state_filter` is not satisfied by partial state.
+                Defaults to `True`.
 
         Returns:
             A dict from (type, state_key) -> state_event_id
@@ -301,7 +325,9 @@ class StateStorageController:
                 outlier or is unknown)
         """
         state_map = await self.get_state_ids_for_events(
-            [event_id], state_filter or StateFilter.all()
+            [event_id],
+            state_filter or StateFilter.all(),
+            await_full_state=await_full_state,
         )
         return state_map[event_id]
 
@@ -323,6 +349,8 @@ class StateStorageController:
             groups, state_filter or StateFilter.all()
         )
 
+    @trace
+    @tag_args
     async def get_state_group_for_events(
         self,
         event_ids: Collection[str],
@@ -334,6 +362,10 @@ class StateStorageController:
             event_ids: events to get state groups for
             await_full_state: if true, will block if we do not yet have complete
                state at these events.
+
+        Raises:
+            RuntimeError if we don't have a state group for one or more of the events
+               (ie. they are outliers or unknown)
         """
         if await_full_state:
             await self._partial_state_events_tracker.await_full_state(event_ids)
@@ -460,6 +492,7 @@ class StateStorageController:
             prev_stream_id, max_stream_id
         )
 
+    @trace
     async def get_current_state(
         self, room_id: str, state_filter: Optional[StateFilter] = None
     ) -> StateMap[EventBase]:
@@ -493,3 +526,15 @@ class StateStorageController:
         await self._partial_state_room_tracker.await_full_state(room_id)
 
         return await self.stores.main.get_current_hosts_in_room(room_id)
+
+    async def get_users_in_room_with_profiles(
+        self, room_id: str
+    ) -> Dict[str, ProfileInfo]:
+        """
+        Get the current users in the room with their profiles.
+        If the room is currently partial-stated, this will block until the room has
+        full state.
+        """
+        await self._partial_state_room_tracker.await_full_state(room_id)
+
+        return await self.stores.main.get_users_in_room_with_profiles(room_id)
diff --git a/synapse/storage/database.py b/synapse/storage/database.py
index ea672ff89e..b394a6658b 100644
--- a/synapse/storage/database.py
+++ b/synapse/storage/database.py
@@ -39,7 +39,7 @@ from typing import (
 )
 
 import attr
-from prometheus_client import Histogram
+from prometheus_client import Counter, Histogram
 from typing_extensions import Concatenate, Literal, ParamSpec
 
 from twisted.enterprise import adbapi
@@ -76,7 +76,8 @@ perf_logger = logging.getLogger("synapse.storage.TIME")
 sql_scheduling_timer = Histogram("synapse_storage_schedule_time", "sec")
 
 sql_query_timer = Histogram("synapse_storage_query_time", "sec", ["verb"])
-sql_txn_timer = Histogram("synapse_storage_transaction_time", "sec", ["desc"])
+sql_txn_count = Counter("synapse_storage_transaction_time_count", "sec", ["desc"])
+sql_txn_duration = Counter("synapse_storage_transaction_time_sum", "sec", ["desc"])
 
 
 # Unique indexes which have been added in background updates. Maps from table name
@@ -795,7 +796,8 @@ class DatabasePool:
 
             self._current_txn_total_time += duration
             self._txn_perf_counters.update(desc, duration)
-            sql_txn_timer.labels(desc).observe(duration)
+            sql_txn_count.labels(desc).inc(1)
+            sql_txn_duration.labels(desc).inc(duration)
 
     async def runInteraction(
         self,
diff --git a/synapse/storage/databases/main/__init__.py b/synapse/storage/databases/main/__init__.py
index a3d31d3737..4dccbb732a 100644
--- a/synapse/storage/databases/main/__init__.py
+++ b/synapse/storage/databases/main/__init__.py
@@ -24,9 +24,9 @@ from synapse.storage.database import (
     LoggingTransaction,
 )
 from synapse.storage.databases.main.stats import UserSortOrder
-from synapse.storage.engines import BaseDatabaseEngine, PostgresEngine
+from synapse.storage.engines import BaseDatabaseEngine
 from synapse.storage.types import Cursor
-from synapse.storage.util.id_generators import MultiWriterIdGenerator, StreamIdGenerator
+from synapse.storage.util.id_generators import StreamIdGenerator
 from synapse.types import JsonDict, get_domain_from_id
 from synapse.util.caches.stream_change_cache import StreamChangeCache
 
@@ -149,31 +149,6 @@ class DataStore(
             ],
         )
 
-        self._cache_id_gen: Optional[MultiWriterIdGenerator]
-        if isinstance(self.database_engine, PostgresEngine):
-            # We set the `writers` to an empty list here as we don't care about
-            # missing updates over restarts, as we'll not have anything in our
-            # caches to invalidate. (This reduces the amount of writes to the DB
-            # that happen).
-            self._cache_id_gen = MultiWriterIdGenerator(
-                db_conn,
-                database,
-                stream_name="caches",
-                instance_name=hs.get_instance_name(),
-                tables=[
-                    (
-                        "cache_invalidation_stream_by_instance",
-                        "instance_name",
-                        "stream_id",
-                    )
-                ],
-                sequence_name="cache_invalidation_stream_seq",
-                writers=[],
-            )
-
-        else:
-            self._cache_id_gen = None
-
         super().__init__(database, db_conn, hs)
 
         events_max = self._stream_id_gen.get_current_token()
diff --git a/synapse/storage/databases/main/account_data.py b/synapse/storage/databases/main/account_data.py
index 9af9f4f18e..c38b8a9e5a 100644
--- a/synapse/storage/databases/main/account_data.py
+++ b/synapse/storage/databases/main/account_data.py
@@ -650,9 +650,6 @@ class AccountDataWorkerStore(PushRulesWorkerStore, CacheInvalidationWorkerStore)
             txn, self.get_account_data_for_room, (user_id,)
         )
         self._invalidate_cache_and_stream(txn, self.get_push_rules_for_user, (user_id,))
-        self._invalidate_cache_and_stream(
-            txn, self.get_push_rules_enabled_for_user, (user_id,)
-        )
         # This user might be contained in the ignored_by cache for other users,
         # so we have to invalidate it all.
         self._invalidate_all_cache_and_stream(txn, self.ignored_by)
diff --git a/synapse/storage/databases/main/cache.py b/synapse/storage/databases/main/cache.py
index 2367ddeea3..12e9a42382 100644
--- a/synapse/storage/databases/main/cache.py
+++ b/synapse/storage/databases/main/cache.py
@@ -32,6 +32,7 @@ from synapse.storage.database import (
     LoggingTransaction,
 )
 from synapse.storage.engines import PostgresEngine
+from synapse.storage.util.id_generators import MultiWriterIdGenerator
 from synapse.util.caches.descriptors import _CachedFunction
 from synapse.util.iterutils import batch_iter
 
@@ -65,6 +66,31 @@ class CacheInvalidationWorkerStore(SQLBaseStore):
             psql_only=True,  # The table is only on postgres DBs.
         )
 
+        self._cache_id_gen: Optional[MultiWriterIdGenerator]
+        if isinstance(self.database_engine, PostgresEngine):
+            # We set the `writers` to an empty list here as we don't care about
+            # missing updates over restarts, as we'll not have anything in our
+            # caches to invalidate. (This reduces the amount of writes to the DB
+            # that happen).
+            self._cache_id_gen = MultiWriterIdGenerator(
+                db_conn,
+                database,
+                stream_name="caches",
+                instance_name=hs.get_instance_name(),
+                tables=[
+                    (
+                        "cache_invalidation_stream_by_instance",
+                        "instance_name",
+                        "stream_id",
+                    )
+                ],
+                sequence_name="cache_invalidation_stream_seq",
+                writers=[],
+            )
+
+        else:
+            self._cache_id_gen = None
+
     async def get_all_updated_caches(
         self, instance_name: str, last_id: int, current_id: int, limit: int
     ) -> Tuple[List[Tuple[int, tuple]], int, bool]:
diff --git a/synapse/storage/databases/main/deviceinbox.py b/synapse/storage/databases/main/deviceinbox.py
index 422e0e65ca..73c95ffb6f 100644
--- a/synapse/storage/databases/main/deviceinbox.py
+++ b/synapse/storage/databases/main/deviceinbox.py
@@ -436,7 +436,7 @@ class DeviceInboxWorkerStore(SQLBaseStore):
             (user_id, device_id), None
         )
 
-        set_tag("last_deleted_stream_id", last_deleted_stream_id)
+        set_tag("last_deleted_stream_id", str(last_deleted_stream_id))
 
         if last_deleted_stream_id:
             has_changed = self._device_inbox_stream_cache.has_entity_changed(
diff --git a/synapse/storage/databases/main/devices.py b/synapse/storage/databases/main/devices.py
index 7a6ed332aa..ca0fe8c4be 100644
--- a/synapse/storage/databases/main/devices.py
+++ b/synapse/storage/databases/main/devices.py
@@ -706,8 +706,8 @@ class DeviceWorkerStore(EndToEndKeyWorkerStore):
             else:
                 results[user_id] = await self.get_cached_devices_for_user(user_id)
 
-        set_tag("in_cache", results)
-        set_tag("not_in_cache", user_ids_not_in_cache)
+        set_tag("in_cache", str(results))
+        set_tag("not_in_cache", str(user_ids_not_in_cache))
 
         return user_ids_not_in_cache, results
 
diff --git a/synapse/storage/databases/main/end_to_end_keys.py b/synapse/storage/databases/main/end_to_end_keys.py
index 60f622ad71..46c0d06157 100644
--- a/synapse/storage/databases/main/end_to_end_keys.py
+++ b/synapse/storage/databases/main/end_to_end_keys.py
@@ -146,7 +146,7 @@ class EndToEndKeyWorkerStore(EndToEndKeyBackgroundStore, CacheInvalidationWorker
             key data.  The key data will be a dict in the same format as the
             DeviceKeys type returned by POST /_matrix/client/r0/keys/query.
         """
-        set_tag("query_list", query_list)
+        set_tag("query_list", str(query_list))
         if not query_list:
             return {}
 
@@ -418,7 +418,7 @@ class EndToEndKeyWorkerStore(EndToEndKeyBackgroundStore, CacheInvalidationWorker
         def _add_e2e_one_time_keys(txn: LoggingTransaction) -> None:
             set_tag("user_id", user_id)
             set_tag("device_id", device_id)
-            set_tag("new_keys", new_keys)
+            set_tag("new_keys", str(new_keys))
             # We are protected from race between lookup and insertion due to
             # a unique constraint. If there is a race of two calls to
             # `add_e2e_one_time_keys` then they'll conflict and we will only
@@ -1161,7 +1161,7 @@ class EndToEndKeyStore(EndToEndKeyWorkerStore, SQLBaseStore):
             set_tag("user_id", user_id)
             set_tag("device_id", device_id)
             set_tag("time_now", time_now)
-            set_tag("device_keys", device_keys)
+            set_tag("device_keys", str(device_keys))
 
             old_key_json = self.db_pool.simple_select_one_onecol_txn(
                 txn,
diff --git a/synapse/storage/databases/main/event_federation.py b/synapse/storage/databases/main/event_federation.py
index eec55b6478..c836078da6 100644
--- a/synapse/storage/databases/main/event_federation.py
+++ b/synapse/storage/databases/main/event_federation.py
@@ -33,6 +33,7 @@ from synapse.api.constants import MAX_DEPTH, EventTypes
 from synapse.api.errors import StoreError
 from synapse.api.room_versions import EventFormatVersions, RoomVersion
 from synapse.events import EventBase, make_event_from_dict
+from synapse.logging.opentracing import tag_args, trace
 from synapse.metrics.background_process_metrics import wrap_as_background_process
 from synapse.storage._base import SQLBaseStore, db_to_json, make_in_list_sql_clause
 from synapse.storage.database import (
@@ -126,6 +127,8 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas
         )
         return await self.get_events_as_list(event_ids)
 
+    @trace
+    @tag_args
     async def get_auth_chain_ids(
         self,
         room_id: str,
@@ -709,6 +712,8 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas
         # Return all events where not all sets can reach them.
         return {eid for eid, n in event_to_missing_sets.items() if n}
 
+    @trace
+    @tag_args
     async def get_oldest_event_ids_with_depth_in_room(
         self, room_id: str
     ) -> List[Tuple[str, int]]:
@@ -767,6 +772,7 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas
             room_id,
         )
 
+    @trace
     async def get_insertion_event_backward_extremities_in_room(
         self, room_id: str
     ) -> List[Tuple[str, int]]:
@@ -1339,6 +1345,8 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas
         event_results.reverse()
         return event_results
 
+    @trace
+    @tag_args
     async def get_successor_events(self, event_id: str) -> List[str]:
         """Fetch all events that have the given event as a prev event
 
@@ -1375,6 +1383,7 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas
             _delete_old_forward_extrem_cache_txn,
         )
 
+    @trace
     async def insert_insertion_extremity(self, event_id: str, room_id: str) -> None:
         await self.db_pool.simple_upsert(
             table="insertion_event_extremities",
diff --git a/synapse/storage/databases/main/event_push_actions.py b/synapse/storage/databases/main/event_push_actions.py
index dd2627037c..eabf9c9739 100644
--- a/synapse/storage/databases/main/event_push_actions.py
+++ b/synapse/storage/databases/main/event_push_actions.py
@@ -12,14 +12,85 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+
+"""Responsible for storing and fetching push actions / notifications.
+
+There are two main uses for push actions:
+  1. Sending out push to a user's device; and
+  2. Tracking per-room per-user notification counts (used in sync requests).
+
+For the former we simply use the `event_push_actions` table, which contains all
+the calculated actions for a given user (which were calculated by the
+`BulkPushRuleEvaluator`).
+
+For the latter we could simply count the number of rows in `event_push_actions`
+table for a given room/user, but in practice this is *very* heavyweight when
+there were a large number of notifications (due to e.g. the user never reading a
+room). Plus, keeping all push actions indefinitely uses a lot of disk space.
+
+To fix these issues, we add a new table `event_push_summary` that tracks
+per-user per-room counts of all notifications that happened before a stream
+ordering S. Thus, to get the notification count for a user / room we can simply
+query a single row in `event_push_summary` and count the number of rows in
+`event_push_actions` with a stream ordering larger than S (and as long as S is
+"recent", the number of rows needing to be scanned will be small).
+
+The `event_push_summary` table is updated via a background job that periodically
+chooses a new stream ordering S' (usually the latest stream ordering), counts
+all notifications in `event_push_actions` between the existing S and S', and
+adds them to the existing counts in `event_push_summary`.
+
+This allows us to delete old rows from `event_push_actions` once those rows have
+been counted and added to `event_push_summary` (we call this process
+"rotation").
+
+
+We need to handle when a user sends a read receipt to the room. Again this is
+done as a background process. For each receipt we clear the row in
+`event_push_summary` and count the number of notifications in
+`event_push_actions` that happened after the receipt but before S, and insert
+that count into `event_push_summary` (If the receipt happened *after* S then we
+simply clear the `event_push_summary`.)
+
+Note that its possible that if the read receipt is for an old event the relevant
+`event_push_actions` rows will have been rotated and we get the wrong count
+(it'll be too low). We accept this as a rare edge case that is unlikely to
+impact the user much (since the vast majority of read receipts will be for the
+latest event).
+
+The last complication is to handle the race where we request the notifications
+counts after a user sends a read receipt into the room, but *before* the
+background update handles the receipt (without any special handling the counts
+would be outdated). We fix this by including in `event_push_summary` the read
+receipt we used when updating `event_push_summary`, and every time we query the
+table we check if that matches the most recent read receipt in the room. If yes,
+continue as above, if not we simply query the `event_push_actions` table
+directly.
+
+Since read receipts are almost always for recent events, scanning the
+`event_push_actions` table in this case is unlikely to be a problem. Even if it
+is a problem, it is temporary until the background job handles the new read
+receipt.
+"""
+
 import logging
-from typing import TYPE_CHECKING, Dict, List, Optional, Tuple, Union, cast
+from typing import (
+    TYPE_CHECKING,
+    Collection,
+    Dict,
+    List,
+    Mapping,
+    Optional,
+    Tuple,
+    Union,
+    cast,
+)
 
 import attr
 
 from synapse.api.constants import ReceiptTypes
 from synapse.metrics.background_process_metrics import wrap_as_background_process
-from synapse.storage._base import SQLBaseStore, db_to_json
+from synapse.storage._base import SQLBaseStore, db_to_json, make_in_list_sql_clause
 from synapse.storage.database import (
     DatabasePool,
     LoggingDatabaseConnection,
@@ -93,7 +164,9 @@ class NotifCounts:
     highlight_count: int = 0
 
 
-def _serialize_action(actions: List[Union[dict, str]], is_highlight: bool) -> str:
+def _serialize_action(
+    actions: Collection[Union[Mapping, str]], is_highlight: bool
+) -> str:
     """Custom serializer for actions. This allows us to "compress" common actions.
 
     We use the fact that most users have the same actions for notifs (and for
@@ -166,7 +239,7 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
         user_id: str,
     ) -> NotifCounts:
         """Get the notification count, the highlight count and the unread message count
-        for a given user in a given room after the given read receipt.
+        for a given user in a given room after their latest read receipt.
 
         Note that this function assumes the user to be a current member of the room,
         since it's either called by the sync handler to handle joined room entries, or by
@@ -177,9 +250,8 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
             user_id: The user to retrieve the counts for.
 
         Returns
-            A dict containing the counts mentioned earlier in this docstring,
-            respectively under the keys "notify_count", "highlight_count" and
-            "unread_count".
+            A NotifCounts object containing the notification count, the highlight count
+            and the unread message count.
         """
         return await self.db_pool.runInteraction(
             "get_unread_event_push_actions_by_room",
@@ -194,20 +266,23 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
         room_id: str,
         user_id: str,
     ) -> NotifCounts:
+        # Get the stream ordering of the user's latest receipt in the room.
         result = self.get_last_receipt_for_user_txn(
             txn,
             user_id,
             room_id,
-            receipt_types=(ReceiptTypes.READ, ReceiptTypes.READ_PRIVATE),
+            receipt_types=(
+                ReceiptTypes.READ,
+                ReceiptTypes.READ_PRIVATE,
+                ReceiptTypes.UNSTABLE_READ_PRIVATE,
+            ),
         )
 
-        stream_ordering = None
         if result:
             _, stream_ordering = result
 
-        if stream_ordering is None:
-            # Either last_read_event_id is None, or it's an event we don't have (e.g.
-            # because it's been purged), in which case retrieve the stream ordering for
+        else:
+            # If the user has no receipts in the room, retrieve the stream ordering for
             # the latest membership event from this user in this room (which we assume is
             # a join).
             event_id = self.db_pool.simple_select_one_onecol_txn(
@@ -224,10 +299,26 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
         )
 
     def _get_unread_counts_by_pos_txn(
-        self, txn: LoggingTransaction, room_id: str, user_id: str, stream_ordering: int
+        self,
+        txn: LoggingTransaction,
+        room_id: str,
+        user_id: str,
+        receipt_stream_ordering: int,
     ) -> NotifCounts:
         """Get the number of unread messages for a user/room that have happened
         since the given stream ordering.
+
+        Args:
+            txn: The database transaction.
+            room_id: The room ID to get unread counts for.
+            user_id: The user ID to get unread counts for.
+            receipt_stream_ordering: The stream ordering of the user's latest
+                receipt in the room. If there are no receipts, the stream ordering
+                of the user's join event.
+
+        Returns
+            A NotifCounts object containing the notification count, the highlight count
+            and the unread message count.
         """
 
         counts = NotifCounts()
@@ -255,7 +346,7 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
                     OR last_receipt_stream_ordering = ?
                 )
             """,
-            (room_id, user_id, stream_ordering, stream_ordering),
+            (room_id, user_id, receipt_stream_ordering, receipt_stream_ordering),
         )
         row = txn.fetchone()
 
@@ -265,7 +356,7 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
             counts.notify_count += row[1]
             counts.unread_count += row[2]
 
-        # Next we need to count highlights, which aren't summarized
+        # Next we need to count highlights, which aren't summarised
         sql = """
             SELECT COUNT(*) FROM event_push_actions
             WHERE user_id = ?
@@ -273,17 +364,20 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
                 AND stream_ordering > ?
                 AND highlight = 1
         """
-        txn.execute(sql, (user_id, room_id, stream_ordering))
+        txn.execute(sql, (user_id, room_id, receipt_stream_ordering))
         row = txn.fetchone()
         if row:
             counts.highlight_count += row[0]
 
         # Finally we need to count push actions that aren't included in the
-        # summary returned above, e.g. recent events that haven't been
-        # summarized yet, or the summary is empty due to a recent read receipt.
-        stream_ordering = max(stream_ordering, summary_stream_ordering)
+        # summary returned above. This might be due to recent events that haven't
+        # been summarised yet or the summary is out of date due to a recent read
+        # receipt.
+        start_unread_stream_ordering = max(
+            receipt_stream_ordering, summary_stream_ordering
+        )
         notify_count, unread_count = self._get_notif_unread_count_for_user_room(
-            txn, room_id, user_id, stream_ordering
+            txn, room_id, user_id, start_unread_stream_ordering
         )
 
         counts.notify_count += notify_count
@@ -304,6 +398,17 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
 
         Does not consult `event_push_summary` table, which may include push
         actions that have been deleted from `event_push_actions` table.
+
+        Args:
+            txn: The database transaction.
+            room_id: The room ID to get unread counts for.
+            user_id: The user ID to get unread counts for.
+            stream_ordering: The (exclusive) minimum stream ordering to consider.
+            max_stream_ordering: The (inclusive) maximum stream ordering to consider.
+                If this is not given, then no maximum is applied.
+
+        Return:
+            A tuple of the notif count and unread count in the given range.
         """
 
         # If there have been no events in the room since the stream ordering,
@@ -376,6 +481,7 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
             The list will be ordered by ascending stream_ordering.
             The list will have between 0~limit entries.
         """
+
         # find rooms that have a read receipt in them and return the next
         # push actions
         def get_after_receipt(
@@ -383,28 +489,41 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
         ) -> List[Tuple[str, str, int, str, bool]]:
             # find rooms that have a read receipt in them and return the next
             # push actions
-            sql = (
-                "SELECT ep.event_id, ep.room_id, ep.stream_ordering, ep.actions,"
-                "   ep.highlight "
-                " FROM ("
-                "   SELECT room_id,"
-                "       MAX(stream_ordering) as stream_ordering"
-                "   FROM events"
-                "   INNER JOIN receipts_linearized USING (room_id, event_id)"
-                "   WHERE receipt_type = 'm.read' AND user_id = ?"
-                "   GROUP BY room_id"
-                ") AS rl,"
-                " event_push_actions AS ep"
-                " WHERE"
-                "   ep.room_id = rl.room_id"
-                "   AND ep.stream_ordering > rl.stream_ordering"
-                "   AND ep.user_id = ?"
-                "   AND ep.stream_ordering > ?"
-                "   AND ep.stream_ordering <= ?"
-                "   AND ep.notif = 1"
-                " ORDER BY ep.stream_ordering ASC LIMIT ?"
+
+            receipt_types_clause, args = make_in_list_sql_clause(
+                self.database_engine,
+                "receipt_type",
+                (
+                    ReceiptTypes.READ,
+                    ReceiptTypes.READ_PRIVATE,
+                    ReceiptTypes.UNSTABLE_READ_PRIVATE,
+                ),
+            )
+
+            sql = f"""
+                SELECT ep.event_id, ep.room_id, ep.stream_ordering, ep.actions,
+                    ep.highlight
+                FROM (
+                    SELECT room_id,
+                        MAX(stream_ordering) as stream_ordering
+                    FROM events
+                    INNER JOIN receipts_linearized USING (room_id, event_id)
+                    WHERE {receipt_types_clause} AND user_id = ?
+                    GROUP BY room_id
+                ) AS rl,
+                event_push_actions AS ep
+                WHERE
+                    ep.room_id = rl.room_id
+                    AND ep.stream_ordering > rl.stream_ordering
+                    AND ep.user_id = ?
+                    AND ep.stream_ordering > ?
+                    AND ep.stream_ordering <= ?
+                    AND ep.notif = 1
+                ORDER BY ep.stream_ordering ASC LIMIT ?
+            """
+            args.extend(
+                (user_id, user_id, min_stream_ordering, max_stream_ordering, limit)
             )
-            args = [user_id, user_id, min_stream_ordering, max_stream_ordering, limit]
             txn.execute(sql, args)
             return cast(List[Tuple[str, str, int, str, bool]], txn.fetchall())
 
@@ -418,24 +537,36 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
         def get_no_receipt(
             txn: LoggingTransaction,
         ) -> List[Tuple[str, str, int, str, bool]]:
-            sql = (
-                "SELECT ep.event_id, ep.room_id, ep.stream_ordering, ep.actions,"
-                "   ep.highlight "
-                " FROM event_push_actions AS ep"
-                " INNER JOIN events AS e USING (room_id, event_id)"
-                " WHERE"
-                "   ep.room_id NOT IN ("
-                "     SELECT room_id FROM receipts_linearized"
-                "       WHERE receipt_type = 'm.read' AND user_id = ?"
-                "       GROUP BY room_id"
-                "   )"
-                "   AND ep.user_id = ?"
-                "   AND ep.stream_ordering > ?"
-                "   AND ep.stream_ordering <= ?"
-                "   AND ep.notif = 1"
-                " ORDER BY ep.stream_ordering ASC LIMIT ?"
+            receipt_types_clause, args = make_in_list_sql_clause(
+                self.database_engine,
+                "receipt_type",
+                (
+                    ReceiptTypes.READ,
+                    ReceiptTypes.READ_PRIVATE,
+                    ReceiptTypes.UNSTABLE_READ_PRIVATE,
+                ),
+            )
+
+            sql = f"""
+                SELECT ep.event_id, ep.room_id, ep.stream_ordering, ep.actions,
+                    ep.highlight
+                FROM event_push_actions AS ep
+                INNER JOIN events AS e USING (room_id, event_id)
+                WHERE
+                    ep.room_id NOT IN (
+                        SELECT room_id FROM receipts_linearized
+                        WHERE {receipt_types_clause} AND user_id = ?
+                        GROUP BY room_id
+                    )
+                    AND ep.user_id = ?
+                    AND ep.stream_ordering > ?
+                    AND ep.stream_ordering <= ?
+                    AND ep.notif = 1
+                ORDER BY ep.stream_ordering ASC LIMIT ?
+            """
+            args.extend(
+                (user_id, user_id, min_stream_ordering, max_stream_ordering, limit)
             )
-            args = [user_id, user_id, min_stream_ordering, max_stream_ordering, limit]
             txn.execute(sql, args)
             return cast(List[Tuple[str, str, int, str, bool]], txn.fetchall())
 
@@ -485,34 +616,47 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
             The list will be ordered by descending received_ts.
             The list will have between 0~limit entries.
         """
+
         # find rooms that have a read receipt in them and return the most recent
         # push actions
         def get_after_receipt(
             txn: LoggingTransaction,
         ) -> List[Tuple[str, str, int, str, bool, int]]:
-            sql = (
-                "SELECT ep.event_id, ep.room_id, ep.stream_ordering, ep.actions,"
-                "  ep.highlight, e.received_ts"
-                " FROM ("
-                "   SELECT room_id,"
-                "       MAX(stream_ordering) as stream_ordering"
-                "   FROM events"
-                "   INNER JOIN receipts_linearized USING (room_id, event_id)"
-                "   WHERE receipt_type = 'm.read' AND user_id = ?"
-                "   GROUP BY room_id"
-                ") AS rl,"
-                " event_push_actions AS ep"
-                " INNER JOIN events AS e USING (room_id, event_id)"
-                " WHERE"
-                "   ep.room_id = rl.room_id"
-                "   AND ep.stream_ordering > rl.stream_ordering"
-                "   AND ep.user_id = ?"
-                "   AND ep.stream_ordering > ?"
-                "   AND ep.stream_ordering <= ?"
-                "   AND ep.notif = 1"
-                " ORDER BY ep.stream_ordering DESC LIMIT ?"
+            receipt_types_clause, args = make_in_list_sql_clause(
+                self.database_engine,
+                "receipt_type",
+                (
+                    ReceiptTypes.READ,
+                    ReceiptTypes.READ_PRIVATE,
+                    ReceiptTypes.UNSTABLE_READ_PRIVATE,
+                ),
+            )
+
+            sql = f"""
+                SELECT ep.event_id, ep.room_id, ep.stream_ordering, ep.actions,
+                    ep.highlight, e.received_ts
+                FROM (
+                    SELECT room_id,
+                        MAX(stream_ordering) as stream_ordering
+                    FROM events
+                    INNER JOIN receipts_linearized USING (room_id, event_id)
+                    WHERE {receipt_types_clause} AND user_id = ?
+                    GROUP BY room_id
+                ) AS rl,
+                event_push_actions AS ep
+                INNER JOIN events AS e USING (room_id, event_id)
+                WHERE
+                    ep.room_id = rl.room_id
+                    AND ep.stream_ordering > rl.stream_ordering
+                    AND ep.user_id = ?
+                    AND ep.stream_ordering > ?
+                    AND ep.stream_ordering <= ?
+                    AND ep.notif = 1
+                ORDER BY ep.stream_ordering DESC LIMIT ?
+            """
+            args.extend(
+                (user_id, user_id, min_stream_ordering, max_stream_ordering, limit)
             )
-            args = [user_id, user_id, min_stream_ordering, max_stream_ordering, limit]
             txn.execute(sql, args)
             return cast(List[Tuple[str, str, int, str, bool, int]], txn.fetchall())
 
@@ -526,24 +670,36 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
         def get_no_receipt(
             txn: LoggingTransaction,
         ) -> List[Tuple[str, str, int, str, bool, int]]:
-            sql = (
-                "SELECT ep.event_id, ep.room_id, ep.stream_ordering, ep.actions,"
-                "   ep.highlight, e.received_ts"
-                " FROM event_push_actions AS ep"
-                " INNER JOIN events AS e USING (room_id, event_id)"
-                " WHERE"
-                "   ep.room_id NOT IN ("
-                "     SELECT room_id FROM receipts_linearized"
-                "       WHERE receipt_type = 'm.read' AND user_id = ?"
-                "       GROUP BY room_id"
-                "   )"
-                "   AND ep.user_id = ?"
-                "   AND ep.stream_ordering > ?"
-                "   AND ep.stream_ordering <= ?"
-                "   AND ep.notif = 1"
-                " ORDER BY ep.stream_ordering DESC LIMIT ?"
+            receipt_types_clause, args = make_in_list_sql_clause(
+                self.database_engine,
+                "receipt_type",
+                (
+                    ReceiptTypes.READ,
+                    ReceiptTypes.READ_PRIVATE,
+                    ReceiptTypes.UNSTABLE_READ_PRIVATE,
+                ),
+            )
+
+            sql = f"""
+                SELECT ep.event_id, ep.room_id, ep.stream_ordering, ep.actions,
+                    ep.highlight, e.received_ts
+                FROM event_push_actions AS ep
+                INNER JOIN events AS e USING (room_id, event_id)
+                WHERE
+                    ep.room_id NOT IN (
+                        SELECT room_id FROM receipts_linearized
+                        WHERE {receipt_types_clause} AND user_id = ?
+                        GROUP BY room_id
+                    )
+                    AND ep.user_id = ?
+                    AND ep.stream_ordering > ?
+                    AND ep.stream_ordering <= ?
+                    AND ep.notif = 1
+                ORDER BY ep.stream_ordering DESC LIMIT ?
+            """
+            args.extend(
+                (user_id, user_id, min_stream_ordering, max_stream_ordering, limit)
             )
-            args = [user_id, user_id, min_stream_ordering, max_stream_ordering, limit]
             txn.execute(sql, args)
             return cast(List[Tuple[str, str, int, str, bool, int]], txn.fetchall())
 
@@ -606,7 +762,7 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
     async def add_push_actions_to_staging(
         self,
         event_id: str,
-        user_id_actions: Dict[str, List[Union[dict, str]]],
+        user_id_actions: Dict[str, Collection[Union[Mapping, str]]],
         count_as_unread: bool,
     ) -> None:
         """Add the push actions for the event to the push action staging area.
@@ -623,7 +779,7 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
         # This is a helper function for generating the necessary tuple that
         # can be used to insert into the `event_push_actions_staging` table.
         def _gen_entry(
-            user_id: str, actions: List[Union[dict, str]]
+            user_id: str, actions: Collection[Union[Mapping, str]]
         ) -> Tuple[str, str, str, int, int, int]:
             is_highlight = 1 if _action_has_highlight(actions) else 0
             notif = 1 if "notify" in actions else 0
@@ -769,12 +925,12 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
         # [10, <none>, 20], we should treat this as being equivalent to
         # [10, 10, 20].
         #
-        sql = (
-            "SELECT received_ts FROM events"
-            " WHERE stream_ordering <= ?"
-            " ORDER BY stream_ordering DESC"
-            " LIMIT 1"
-        )
+        sql = """
+            SELECT received_ts FROM events
+            WHERE stream_ordering <= ?
+            ORDER BY stream_ordering DESC
+            LIMIT 1
+        """
 
         while range_end - range_start > 0:
             middle = (range_end + range_start) // 2
@@ -802,14 +958,14 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
         self, stream_ordering: int
     ) -> Optional[int]:
         def f(txn: LoggingTransaction) -> Optional[Tuple[int]]:
-            sql = (
-                "SELECT e.received_ts"
-                " FROM event_push_actions AS ep"
-                " JOIN events e ON ep.room_id = e.room_id AND ep.event_id = e.event_id"
-                " WHERE ep.stream_ordering > ? AND notif = 1"
-                " ORDER BY ep.stream_ordering ASC"
-                " LIMIT 1"
-            )
+            sql = """
+                SELECT e.received_ts
+                FROM event_push_actions AS ep
+                JOIN events e ON ep.room_id = e.room_id AND ep.event_id = e.event_id
+                WHERE ep.stream_ordering > ? AND notif = 1
+                ORDER BY ep.stream_ordering ASC
+                LIMIT 1
+            """
             txn.execute(sql, (stream_ordering,))
             return cast(Optional[Tuple[int]], txn.fetchone())
 
@@ -858,10 +1014,13 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
         Any push actions which predate the user's most recent read receipt are
         now redundant, so we can remove them from `event_push_actions` and
         update `event_push_summary`.
+
+        Returns true if all new receipts have been processed.
         """
 
         limit = 100
 
+        # The (inclusive) receipt stream ID that was previously processed..
         min_receipts_stream_id = self.db_pool.simple_select_one_onecol_txn(
             txn,
             table="event_push_summary_last_receipt_stream_id",
@@ -871,6 +1030,14 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
 
         max_receipts_stream_id = self._receipts_id_gen.get_current_token()
 
+        # The (inclusive) event stream ordering that was previously summarised.
+        old_rotate_stream_ordering = self.db_pool.simple_select_one_onecol_txn(
+            txn,
+            table="event_push_summary_stream_ordering",
+            keyvalues={},
+            retcol="stream_ordering",
+        )
+
         sql = """
             SELECT r.stream_id, r.room_id, r.user_id, e.stream_ordering
             FROM receipts_linearized AS r
@@ -895,13 +1062,6 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
         )
         rows = txn.fetchall()
 
-        old_rotate_stream_ordering = self.db_pool.simple_select_one_onecol_txn(
-            txn,
-            table="event_push_summary_stream_ordering",
-            keyvalues={},
-            retcol="stream_ordering",
-        )
-
         # For each new read receipt we delete push actions from before it and
         # recalculate the summary.
         for _, room_id, user_id, stream_ordering in rows:
@@ -920,10 +1080,13 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
                 (room_id, user_id, stream_ordering),
             )
 
+            # Fetch the notification counts between the stream ordering of the
+            # latest receipt and what was previously summarised.
             notif_count, unread_count = self._get_notif_unread_count_for_user_room(
                 txn, room_id, user_id, stream_ordering, old_rotate_stream_ordering
             )
 
+            # Replace the previous summary with the new counts.
             self.db_pool.simple_upsert_txn(
                 txn,
                 table="event_push_summary",
@@ -956,10 +1119,12 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
         return len(rows) < limit
 
     def _rotate_notifs_txn(self, txn: LoggingTransaction) -> bool:
-        """Archives older notifications into event_push_summary. Returns whether
-        the archiving process has caught up or not.
+        """Archives older notifications (from event_push_actions) into event_push_summary.
+
+        Returns whether the archiving process has caught up or not.
         """
 
+        # The (inclusive) event stream ordering that was previously summarised.
         old_rotate_stream_ordering = self.db_pool.simple_select_one_onecol_txn(
             txn,
             table="event_push_summary_stream_ordering",
@@ -974,7 +1139,7 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
             SELECT stream_ordering FROM event_push_actions
             WHERE stream_ordering > ?
             ORDER BY stream_ordering ASC LIMIT 1 OFFSET ?
-        """,
+            """,
             (old_rotate_stream_ordering, self._rotate_count),
         )
         stream_row = txn.fetchone()
@@ -993,19 +1158,29 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
 
         logger.info("Rotating notifications up to: %s", rotate_to_stream_ordering)
 
-        self._rotate_notifs_before_txn(txn, rotate_to_stream_ordering)
+        self._rotate_notifs_before_txn(
+            txn, old_rotate_stream_ordering, rotate_to_stream_ordering
+        )
 
         return caught_up
 
     def _rotate_notifs_before_txn(
-        self, txn: LoggingTransaction, rotate_to_stream_ordering: int
+        self,
+        txn: LoggingTransaction,
+        old_rotate_stream_ordering: int,
+        rotate_to_stream_ordering: int,
     ) -> None:
-        old_rotate_stream_ordering = self.db_pool.simple_select_one_onecol_txn(
-            txn,
-            table="event_push_summary_stream_ordering",
-            keyvalues={},
-            retcol="stream_ordering",
-        )
+        """Archives older notifications (from event_push_actions) into event_push_summary.
+
+        Any event_push_actions between old_rotate_stream_ordering (exclusive) and
+        rotate_to_stream_ordering (inclusive) will be added to the event_push_summary
+        table.
+
+        Args:
+            txn: The database transaction.
+            old_rotate_stream_ordering: The previous maximum event stream ordering.
+            rotate_to_stream_ordering: The new maximum event stream ordering to summarise.
+        """
 
         # Calculate the new counts that should be upserted into event_push_summary
         sql = """
@@ -1090,12 +1265,10 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
             (rotate_to_stream_ordering,),
         )
 
-    async def _remove_old_push_actions_that_have_rotated(
-        self,
-    ) -> None:
-        """Clear out old push actions that have been summarized."""
+    async def _remove_old_push_actions_that_have_rotated(self) -> None:
+        """Clear out old push actions that have been summarised."""
 
-        # We want to clear out anything that older than a day that *has* already
+        # We want to clear out anything that is older than a day that *has* already
         # been rotated.
         rotated_upto_stream_ordering = await self.db_pool.simple_select_one_onecol(
             table="event_push_summary_stream_ordering",
@@ -1119,7 +1292,7 @@ class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBas
                 SELECT stream_ordering FROM event_push_actions
                 WHERE stream_ordering <= ? AND highlight = 0
                 ORDER BY stream_ordering ASC LIMIT 1 OFFSET ?
-            """,
+                """,
                 (
                     max_stream_ordering_to_delete,
                     batch_size,
@@ -1215,16 +1388,18 @@ class EventPushActionsStore(EventPushActionsWorkerStore):
 
             # NB. This assumes event_ids are globally unique since
             # it makes the query easier to index
-            sql = (
-                "SELECT epa.event_id, epa.room_id,"
-                " epa.stream_ordering, epa.topological_ordering,"
-                " epa.actions, epa.highlight, epa.profile_tag, e.received_ts"
-                " FROM event_push_actions epa, events e"
-                " WHERE epa.event_id = e.event_id"
-                " AND epa.user_id = ? %s"
-                " AND epa.notif = 1"
-                " ORDER BY epa.stream_ordering DESC"
-                " LIMIT ?" % (before_clause,)
+            sql = """
+                SELECT epa.event_id, epa.room_id,
+                    epa.stream_ordering, epa.topological_ordering,
+                    epa.actions, epa.highlight, epa.profile_tag, e.received_ts
+                FROM event_push_actions epa, events e
+                WHERE epa.event_id = e.event_id
+                    AND epa.user_id = ? %s
+                    AND epa.notif = 1
+                ORDER BY epa.stream_ordering DESC
+                LIMIT ?
+            """ % (
+                before_clause,
             )
             txn.execute(sql, args)
             return cast(
@@ -1247,7 +1422,7 @@ class EventPushActionsStore(EventPushActionsWorkerStore):
         ]
 
 
-def _action_has_highlight(actions: List[Union[dict, str]]) -> bool:
+def _action_has_highlight(actions: Collection[Union[Mapping, str]]) -> bool:
     for action in actions:
         if not isinstance(action, dict):
             continue
diff --git a/synapse/storage/databases/main/events.py b/synapse/storage/databases/main/events.py
index 1f600f1190..a4010ee28d 100644
--- a/synapse/storage/databases/main/events.py
+++ b/synapse/storage/databases/main/events.py
@@ -40,6 +40,7 @@ from synapse.api.errors import Codes, SynapseError
 from synapse.api.room_versions import RoomVersions
 from synapse.events import EventBase, relation_from_event
 from synapse.events.snapshot import EventContext
+from synapse.logging.opentracing import trace
 from synapse.storage._base import db_to_json, make_in_list_sql_clause
 from synapse.storage.database import (
     DatabasePool,
@@ -145,6 +146,7 @@ class PersistEventsStore:
         self._backfill_id_gen: AbstractStreamIdGenerator = self.store._backfill_id_gen
         self._stream_id_gen: AbstractStreamIdGenerator = self.store._stream_id_gen
 
+    @trace
     async def _persist_events_and_state_updates(
         self,
         events_and_contexts: List[Tuple[EventBase, EventContext]],
@@ -1490,7 +1492,7 @@ class PersistEventsStore:
                     event.sender,
                     "url" in event.content and isinstance(event.content["url"], str),
                     event.get_state_key(),
-                    context.rejected or None,
+                    context.rejected,
                 )
                 for event, context in events_and_contexts
             ),
diff --git a/synapse/storage/databases/main/events_worker.py b/synapse/storage/databases/main/events_worker.py
index 5914a35420..8a7cdb024d 100644
--- a/synapse/storage/databases/main/events_worker.py
+++ b/synapse/storage/databases/main/events_worker.py
@@ -54,6 +54,7 @@ from synapse.logging.context import (
     current_context,
     make_deferred_yieldable,
 )
+from synapse.logging.opentracing import start_active_span, tag_args, trace
 from synapse.metrics.background_process_metrics import (
     run_as_background_process,
     wrap_as_background_process,
@@ -430,6 +431,8 @@ class EventsWorkerStore(SQLBaseStore):
 
         return {e.event_id: e for e in events}
 
+    @trace
+    @tag_args
     async def get_events_as_list(
         self,
         event_ids: Collection[str],
@@ -600,7 +603,11 @@ class EventsWorkerStore(SQLBaseStore):
         Returns:
             map from event id to result
         """
-        event_entry_map = await self._get_events_from_cache(
+        # Shortcut: check if we have any events in the *in memory* cache - this function
+        # may be called repeatedly for the same event so at this point we cannot reach
+        # out to any external cache for performance reasons. The external cache is
+        # checked later on in the `get_missing_events_from_cache_or_db` function below.
+        event_entry_map = self._get_events_from_local_cache(
             event_ids,
         )
 
@@ -632,7 +639,9 @@ class EventsWorkerStore(SQLBaseStore):
 
         if missing_events_ids:
 
-            async def get_missing_events_from_db() -> Dict[str, EventCacheEntry]:
+            async def get_missing_events_from_cache_or_db() -> Dict[
+                str, EventCacheEntry
+            ]:
                 """Fetches the events in `missing_event_ids` from the database.
 
                 Also creates entries in `self._current_event_fetches` to allow
@@ -657,10 +666,18 @@ class EventsWorkerStore(SQLBaseStore):
                 # the events have been redacted, and if so pulling the redaction event
                 # out of the database to check it.
                 #
+                missing_events = {}
                 try:
-                    missing_events = await self._get_events_from_db(
+                    # Try to fetch from any external cache. We already checked the
+                    # in-memory cache above.
+                    missing_events = await self._get_events_from_external_cache(
                         missing_events_ids,
                     )
+                    # Now actually fetch any remaining events from the DB
+                    db_missing_events = await self._get_events_from_db(
+                        missing_events_ids - missing_events.keys(),
+                    )
+                    missing_events.update(db_missing_events)
                 except Exception as e:
                     with PreserveLoggingContext():
                         fetching_deferred.errback(e)
@@ -679,7 +696,7 @@ class EventsWorkerStore(SQLBaseStore):
             # cancellations, since multiple `_get_events_from_cache_or_db` calls can
             # reuse the same fetch.
             missing_events: Dict[str, EventCacheEntry] = await delay_cancellation(
-                get_missing_events_from_db()
+                get_missing_events_from_cache_or_db()
             )
             event_entry_map.update(missing_events)
 
@@ -754,7 +771,54 @@ class EventsWorkerStore(SQLBaseStore):
     async def _get_events_from_cache(
         self, events: Iterable[str], update_metrics: bool = True
     ) -> Dict[str, EventCacheEntry]:
-        """Fetch events from the caches.
+        """Fetch events from the caches, both in memory and any external.
+
+        May return rejected events.
+
+        Args:
+            events: list of event_ids to fetch
+            update_metrics: Whether to update the cache hit ratio metrics
+        """
+        event_map = self._get_events_from_local_cache(
+            events, update_metrics=update_metrics
+        )
+
+        missing_event_ids = (e for e in events if e not in event_map)
+        event_map.update(
+            await self._get_events_from_external_cache(
+                events=missing_event_ids,
+                update_metrics=update_metrics,
+            )
+        )
+
+        return event_map
+
+    async def _get_events_from_external_cache(
+        self, events: Iterable[str], update_metrics: bool = True
+    ) -> Dict[str, EventCacheEntry]:
+        """Fetch events from any configured external cache.
+
+        May return rejected events.
+
+        Args:
+            events: list of event_ids to fetch
+            update_metrics: Whether to update the cache hit ratio metrics
+        """
+        event_map = {}
+
+        for event_id in events:
+            ret = await self._get_event_cache.get_external(
+                (event_id,), None, update_metrics=update_metrics
+            )
+            if ret:
+                event_map[event_id] = ret
+
+        return event_map
+
+    def _get_events_from_local_cache(
+        self, events: Iterable[str], update_metrics: bool = True
+    ) -> Dict[str, EventCacheEntry]:
+        """Fetch events from the local, in memory, caches.
 
         May return rejected events.
 
@@ -766,7 +830,7 @@ class EventsWorkerStore(SQLBaseStore):
 
         for event_id in events:
             # First check if it's in the event cache
-            ret = await self._get_event_cache.get(
+            ret = self._get_event_cache.get_local(
                 (event_id,), None, update_metrics=update_metrics
             )
             if ret:
@@ -788,7 +852,7 @@ class EventsWorkerStore(SQLBaseStore):
 
                 # We add the entry back into the cache as we want to keep
                 # recently queried events in the cache.
-                await self._get_event_cache.set((event_id,), cache_entry)
+                self._get_event_cache.set_local((event_id,), cache_entry)
 
         return event_map
 
@@ -1029,23 +1093,42 @@ class EventsWorkerStore(SQLBaseStore):
         """
         fetched_event_ids: Set[str] = set()
         fetched_events: Dict[str, _EventRow] = {}
-        events_to_fetch = event_ids
 
-        while events_to_fetch:
-            row_map = await self._enqueue_events(events_to_fetch)
+        async def _fetch_event_ids_and_get_outstanding_redactions(
+            event_ids_to_fetch: Collection[str],
+        ) -> Collection[str]:
+            """
+            Fetch all of the given event_ids and return any associated redaction event_ids
+            that we still need to fetch in the next iteration.
+            """
+            row_map = await self._enqueue_events(event_ids_to_fetch)
 
             # we need to recursively fetch any redactions of those events
             redaction_ids: Set[str] = set()
-            for event_id in events_to_fetch:
+            for event_id in event_ids_to_fetch:
                 row = row_map.get(event_id)
                 fetched_event_ids.add(event_id)
                 if row:
                     fetched_events[event_id] = row
                     redaction_ids.update(row.redactions)
 
-            events_to_fetch = redaction_ids.difference(fetched_event_ids)
-            if events_to_fetch:
-                logger.debug("Also fetching redaction events %s", events_to_fetch)
+            event_ids_to_fetch = redaction_ids.difference(fetched_event_ids)
+            return event_ids_to_fetch
+
+        # Grab the initial list of events requested
+        event_ids_to_fetch = await _fetch_event_ids_and_get_outstanding_redactions(
+            event_ids
+        )
+        # Then go and recursively find all of the associated redactions
+        with start_active_span("recursively fetching redactions"):
+            while event_ids_to_fetch:
+                logger.debug("Also fetching redaction events %s", event_ids_to_fetch)
+
+                event_ids_to_fetch = (
+                    await _fetch_event_ids_and_get_outstanding_redactions(
+                        event_ids_to_fetch
+                    )
+                )
 
         # build a map from event_id to EventBase
         event_map: Dict[str, EventBase] = {}
@@ -1363,6 +1446,8 @@ class EventsWorkerStore(SQLBaseStore):
 
         return {r["event_id"] for r in rows}
 
+    @trace
+    @tag_args
     async def have_seen_events(
         self, room_id: str, event_ids: Iterable[str]
     ) -> Set[str]:
@@ -2110,14 +2195,92 @@ class EventsWorkerStore(SQLBaseStore):
     def _get_partial_state_events_batch_txn(
         txn: LoggingTransaction, room_id: str
     ) -> List[str]:
+        # we want to work through the events from oldest to newest, so
+        # we only want events whose prev_events do *not* have partial state - hence
+        # the 'NOT EXISTS' clause in the below.
+        #
+        # This is necessary because ordering by stream ordering isn't quite enough
+        # to ensure that we work from oldest to newest event (in particular,
+        # if an event is initially persisted as an outlier and later de-outliered,
+        # it can end up with a lower stream_ordering than its prev_events).
+        #
+        # Typically this means we'll only return one event per batch, but that's
+        # hard to do much about.
+        #
+        # See also: https://github.com/matrix-org/synapse/issues/13001
         txn.execute(
             """
             SELECT event_id FROM partial_state_events AS pse
                 JOIN events USING (event_id)
-            WHERE pse.room_id = ?
+            WHERE pse.room_id = ? AND
+               NOT EXISTS(
+                  SELECT 1 FROM event_edges AS ee
+                     JOIN partial_state_events AS prev_pse ON (prev_pse.event_id=ee.prev_event_id)
+                     WHERE ee.event_id=pse.event_id
+               )
             ORDER BY events.stream_ordering
             LIMIT 100
             """,
             (room_id,),
         )
         return [row[0] for row in txn]
+
+    def mark_event_rejected_txn(
+        self,
+        txn: LoggingTransaction,
+        event_id: str,
+        rejection_reason: Optional[str],
+    ) -> None:
+        """Mark an event that was previously accepted as rejected, or vice versa
+
+        This can happen, for example, when resyncing state during a faster join.
+
+        Args:
+            txn:
+            event_id: ID of event to update
+            rejection_reason: reason it has been rejected, or None if it is now accepted
+        """
+        if rejection_reason is None:
+            logger.info(
+                "Marking previously-processed event %s as accepted",
+                event_id,
+            )
+            self.db_pool.simple_delete_txn(
+                txn,
+                "rejections",
+                keyvalues={"event_id": event_id},
+            )
+        else:
+            logger.info(
+                "Marking previously-processed event %s as rejected(%s)",
+                event_id,
+                rejection_reason,
+            )
+            self.db_pool.simple_upsert_txn(
+                txn,
+                table="rejections",
+                keyvalues={"event_id": event_id},
+                values={
+                    "reason": rejection_reason,
+                    "last_check": self._clock.time_msec(),
+                },
+            )
+        self.db_pool.simple_update_txn(
+            txn,
+            table="events",
+            keyvalues={"event_id": event_id},
+            updatevalues={"rejection_reason": rejection_reason},
+        )
+
+        self.invalidate_get_event_cache_after_txn(txn, event_id)
+
+        # TODO(faster_joins): invalidate the cache on workers. Ideally we'd just
+        #   call '_send_invalidation_to_replication', but we actually need the other
+        #   end to call _invalidate_local_get_event_cache() rather than (just)
+        #   _get_event_cache.invalidate().
+        #
+        #   One solution might be to (somehow) get the workers to call
+        #   _invalidate_caches_for_event() (though that will invalidate more than
+        #   strictly necessary).
+        #
+        #   https://github.com/matrix-org/synapse/issues/12994
diff --git a/synapse/storage/databases/main/push_rule.py b/synapse/storage/databases/main/push_rule.py
index 768f95d16c..5079edd1e0 100644
--- a/synapse/storage/databases/main/push_rule.py
+++ b/synapse/storage/databases/main/push_rule.py
@@ -14,11 +14,23 @@
 # limitations under the License.
 import abc
 import logging
-from typing import TYPE_CHECKING, Collection, Dict, List, Optional, Tuple, Union, cast
+from typing import (
+    TYPE_CHECKING,
+    Any,
+    Collection,
+    Dict,
+    List,
+    Mapping,
+    Optional,
+    Sequence,
+    Tuple,
+    Union,
+    cast,
+)
 
 from synapse.api.errors import StoreError
 from synapse.config.homeserver import ExperimentalConfig
-from synapse.push.baserules import list_with_base_rules
+from synapse.push.baserules import FilteredPushRules, PushRule, compile_push_rules
 from synapse.replication.slave.storage._slaved_id_tracker import SlavedIdTracker
 from synapse.storage._base import SQLBaseStore, db_to_json
 from synapse.storage.database import (
@@ -50,60 +62,30 @@ if TYPE_CHECKING:
 logger = logging.getLogger(__name__)
 
 
-def _is_experimental_rule_enabled(
-    rule_id: str, experimental_config: ExperimentalConfig
-) -> bool:
-    """Used by `_load_rules` to filter out experimental rules when they
-    have not been enabled.
-    """
-    if (
-        rule_id == "global/override/.org.matrix.msc3786.rule.room.server_acl"
-        and not experimental_config.msc3786_enabled
-    ):
-        return False
-    if (
-        rule_id == "global/underride/.org.matrix.msc3772.thread_reply"
-        and not experimental_config.msc3772_enabled
-    ):
-        return False
-    return True
-
-
 def _load_rules(
     rawrules: List[JsonDict],
     enabled_map: Dict[str, bool],
     experimental_config: ExperimentalConfig,
-) -> List[JsonDict]:
-    ruleslist = []
-    for rawrule in rawrules:
-        rule = dict(rawrule)
-        rule["conditions"] = db_to_json(rawrule["conditions"])
-        rule["actions"] = db_to_json(rawrule["actions"])
-        rule["default"] = False
-        ruleslist.append(rule)
-
-    # We're going to be mutating this a lot, so copy it. We also filter out
-    # any experimental default push rules that aren't enabled.
-    rules = [
-        rule
-        for rule in list_with_base_rules(ruleslist)
-        if _is_experimental_rule_enabled(rule["rule_id"], experimental_config)
-    ]
+) -> FilteredPushRules:
+    """Take the DB rows returned from the DB and convert them into a full
+    `FilteredPushRules` object.
+    """
 
-    for i, rule in enumerate(rules):
-        rule_id = rule["rule_id"]
+    ruleslist = [
+        PushRule(
+            rule_id=rawrule["rule_id"],
+            priority_class=rawrule["priority_class"],
+            conditions=db_to_json(rawrule["conditions"]),
+            actions=db_to_json(rawrule["actions"]),
+        )
+        for rawrule in rawrules
+    ]
 
-        if rule_id not in enabled_map:
-            continue
-        if rule.get("enabled", True) == bool(enabled_map[rule_id]):
-            continue
+    push_rules = compile_push_rules(ruleslist)
 
-        # Rules are cached across users.
-        rule = dict(rule)
-        rule["enabled"] = bool(enabled_map[rule_id])
-        rules[i] = rule
+    filtered_rules = FilteredPushRules(push_rules, enabled_map, experimental_config)
 
-    return rules
+    return filtered_rules
 
 
 # The ABCMeta metaclass ensures that it cannot be instantiated without
@@ -162,7 +144,7 @@ class PushRulesWorkerStore(
         raise NotImplementedError()
 
     @cached(max_entries=5000)
-    async def get_push_rules_for_user(self, user_id: str) -> List[JsonDict]:
+    async def get_push_rules_for_user(self, user_id: str) -> FilteredPushRules:
         rows = await self.db_pool.simple_select_list(
             table="push_rules",
             keyvalues={"user_name": user_id},
@@ -183,7 +165,6 @@ class PushRulesWorkerStore(
 
         return _load_rules(rows, enabled_map, self.hs.config.experimental)
 
-    @cached(max_entries=5000)
     async def get_push_rules_enabled_for_user(self, user_id: str) -> Dict[str, bool]:
         results = await self.db_pool.simple_select_list(
             table="push_rules_enable",
@@ -216,11 +197,11 @@ class PushRulesWorkerStore(
     @cachedList(cached_method_name="get_push_rules_for_user", list_name="user_ids")
     async def bulk_get_push_rules(
         self, user_ids: Collection[str]
-    ) -> Dict[str, List[JsonDict]]:
+    ) -> Dict[str, FilteredPushRules]:
         if not user_ids:
             return {}
 
-        results: Dict[str, List[JsonDict]] = {user_id: [] for user_id in user_ids}
+        raw_rules: Dict[str, List[JsonDict]] = {user_id: [] for user_id in user_ids}
 
         rows = await self.db_pool.simple_select_many_batch(
             table="push_rules",
@@ -234,20 +215,19 @@ class PushRulesWorkerStore(
         rows.sort(key=lambda row: (-int(row["priority_class"]), -int(row["priority"])))
 
         for row in rows:
-            results.setdefault(row["user_name"], []).append(row)
+            raw_rules.setdefault(row["user_name"], []).append(row)
 
         enabled_map_by_user = await self.bulk_get_push_rules_enabled(user_ids)
 
-        for user_id, rules in results.items():
+        results: Dict[str, FilteredPushRules] = {}
+
+        for user_id, rules in raw_rules.items():
             results[user_id] = _load_rules(
                 rules, enabled_map_by_user.get(user_id, {}), self.hs.config.experimental
             )
 
         return results
 
-    @cachedList(
-        cached_method_name="get_push_rules_enabled_for_user", list_name="user_ids"
-    )
     async def bulk_get_push_rules_enabled(
         self, user_ids: Collection[str]
     ) -> Dict[str, Dict[str, bool]]:
@@ -262,6 +242,7 @@ class PushRulesWorkerStore(
             iterable=user_ids,
             retcols=("user_name", "rule_id", "enabled"),
             desc="bulk_get_push_rules_enabled",
+            batch_size=1000,
         )
         for row in rows:
             enabled = bool(row["enabled"])
@@ -345,8 +326,8 @@ class PushRuleStore(PushRulesWorkerStore):
         user_id: str,
         rule_id: str,
         priority_class: int,
-        conditions: List[Dict[str, str]],
-        actions: List[Union[JsonDict, str]],
+        conditions: Sequence[Mapping[str, str]],
+        actions: Sequence[Union[Mapping[str, Any], str]],
         before: Optional[str] = None,
         after: Optional[str] = None,
     ) -> None:
@@ -808,7 +789,6 @@ class PushRuleStore(PushRulesWorkerStore):
         self.db_pool.simple_insert_txn(txn, "push_rules_stream", values=values)
 
         txn.call_after(self.get_push_rules_for_user.invalidate, (user_id,))
-        txn.call_after(self.get_push_rules_enabled_for_user.invalidate, (user_id,))
         txn.call_after(
             self.push_rules_stream_cache.entity_has_changed, user_id, stream_id
         )
@@ -817,7 +797,7 @@ class PushRuleStore(PushRulesWorkerStore):
         return self._push_rules_stream_id_gen.get_current_token()
 
     async def copy_push_rule_from_room_to_room(
-        self, new_room_id: str, user_id: str, rule: dict
+        self, new_room_id: str, user_id: str, rule: PushRule
     ) -> None:
         """Copy a single push rule from one room to another for a specific user.
 
@@ -827,21 +807,27 @@ class PushRuleStore(PushRulesWorkerStore):
             rule: A push rule.
         """
         # Create new rule id
-        rule_id_scope = "/".join(rule["rule_id"].split("/")[:-1])
+        rule_id_scope = "/".join(rule.rule_id.split("/")[:-1])
         new_rule_id = rule_id_scope + "/" + new_room_id
 
+        new_conditions = []
+
         # Change room id in each condition
-        for condition in rule.get("conditions", []):
+        for condition in rule.conditions:
+            new_condition = condition
             if condition.get("key") == "room_id":
-                condition["pattern"] = new_room_id
+                new_condition = dict(condition)
+                new_condition["pattern"] = new_room_id
+
+            new_conditions.append(new_condition)
 
         # Add the rule for the new room
         await self.add_push_rule(
             user_id=user_id,
             rule_id=new_rule_id,
-            priority_class=rule["priority_class"],
-            conditions=rule["conditions"],
-            actions=rule["actions"],
+            priority_class=rule.priority_class,
+            conditions=new_conditions,
+            actions=rule.actions,
         )
 
     async def copy_push_rules_from_room_to_room_for_user(
@@ -859,8 +845,11 @@ class PushRuleStore(PushRulesWorkerStore):
         user_push_rules = await self.get_push_rules_for_user(user_id)
 
         # Get rules relating to the old room and copy them to the new room
-        for rule in user_push_rules:
-            conditions = rule.get("conditions", [])
+        for rule, enabled in user_push_rules:
+            if not enabled:
+                continue
+
+            conditions = rule.conditions
             if any(
                 (c.get("key") == "room_id" and c.get("pattern") == old_room_id)
                 for c in conditions
diff --git a/synapse/storage/databases/main/receipts.py b/synapse/storage/databases/main/receipts.py
index 0090c9f225..124c70ad37 100644
--- a/synapse/storage/databases/main/receipts.py
+++ b/synapse/storage/databases/main/receipts.py
@@ -161,7 +161,7 @@ class ReceiptsWorkerStore(SQLBaseStore):
             receipt_type: The receipt types to fetch.
 
         Returns:
-            The latest receipt, if one exists.
+            The event ID and stream ordering of the latest receipt, if one exists.
         """
 
         clause, args = make_in_list_sql_clause(
diff --git a/synapse/storage/databases/main/registration.py b/synapse/storage/databases/main/registration.py
index cb63cd9b7d..7fb9c801da 100644
--- a/synapse/storage/databases/main/registration.py
+++ b/synapse/storage/databases/main/registration.py
@@ -69,9 +69,9 @@ class TokenLookupResult:
     """
 
     user_id: str
+    token_id: int
     is_guest: bool = False
     shadow_banned: bool = False
-    token_id: Optional[int] = None
     device_id: Optional[str] = None
     valid_until_ms: Optional[int] = None
     token_owner: str = attr.ib()
diff --git a/synapse/storage/databases/main/relations.py b/synapse/storage/databases/main/relations.py
index b457bc189e..7bd27790eb 100644
--- a/synapse/storage/databases/main/relations.py
+++ b/synapse/storage/databases/main/relations.py
@@ -62,7 +62,6 @@ class RelationsWorkerStore(SQLBaseStore):
         room_id: str,
         relation_type: Optional[str] = None,
         event_type: Optional[str] = None,
-        aggregation_key: Optional[str] = None,
         limit: int = 5,
         direction: str = "b",
         from_token: Optional[StreamToken] = None,
@@ -76,7 +75,6 @@ class RelationsWorkerStore(SQLBaseStore):
             room_id: The room the event belongs to.
             relation_type: Only fetch events with this relation type, if given.
             event_type: Only fetch events with this event type, if given.
-            aggregation_key: Only fetch events with this aggregation key, if given.
             limit: Only fetch the most recent `limit` events.
             direction: Whether to fetch the most recent first (`"b"`) or the
                 oldest first (`"f"`).
@@ -105,10 +103,6 @@ class RelationsWorkerStore(SQLBaseStore):
             where_clause.append("type = ?")
             where_args.append(event_type)
 
-        if aggregation_key:
-            where_clause.append("aggregation_key = ?")
-            where_args.append(aggregation_key)
-
         pagination_clause = generate_pagination_where_clause(
             direction=direction,
             column_names=("topological_ordering", "stream_ordering"),
diff --git a/synapse/storage/databases/main/room.py b/synapse/storage/databases/main/room.py
index d6d485507b..b7d4baa6bb 100644
--- a/synapse/storage/databases/main/room.py
+++ b/synapse/storage/databases/main/room.py
@@ -207,7 +207,7 @@ class RoomWorkerStore(CacheInvalidationWorkerStore):
     def _construct_room_type_where_clause(
         self, room_types: Union[List[Union[str, None]], None]
     ) -> Tuple[Union[str, None], List[str]]:
-        if not room_types or not self.config.experimental.msc3827_enabled:
+        if not room_types:
             return None, []
         else:
             # We use None when we want get rooms without a type
@@ -2001,9 +2001,15 @@ class RoomStore(RoomBackgroundUpdateStore, RoomWorkerStore):
 
             where_clause = "WHERE " + " AND ".join(filters) if len(filters) > 0 else ""
 
+            # We join on room_stats_state despite not using any columns from it
+            # because the join can influence the number of rows returned;
+            # e.g. a room that doesn't have state, maybe because it was deleted.
+            # The query returning the total count should be consistent with
+            # the query returning the results.
             sql = """
                 SELECT COUNT(*) as total_event_reports
                 FROM event_reports AS er
+                JOIN room_stats_state ON room_stats_state.room_id = er.room_id
                 {}
                 """.format(
                 where_clause
diff --git a/synapse/storage/databases/main/roommember.py b/synapse/storage/databases/main/roommember.py
index df6b82660e..046ad3a11c 100644
--- a/synapse/storage/databases/main/roommember.py
+++ b/synapse/storage/databases/main/roommember.py
@@ -21,6 +21,7 @@ from typing import (
     FrozenSet,
     Iterable,
     List,
+    Mapping,
     Optional,
     Set,
     Tuple,
@@ -55,6 +56,7 @@ from synapse.types import JsonDict, PersistedEventPosition, StateMap, get_domain
 from synapse.util.async_helpers import Linearizer
 from synapse.util.caches import intern_string
 from synapse.util.caches.descriptors import _CacheContext, cached, cachedList
+from synapse.util.iterutils import batch_iter
 from synapse.util.metrics import Measure
 
 if TYPE_CHECKING:
@@ -183,7 +185,7 @@ class RoomMemberWorkerStore(EventsWorkerStore):
                 self._check_safe_current_state_events_membership_updated_txn,
             )
 
-    @cached(max_entries=100000, iterable=True, prune_unread_entries=False)
+    @cached(max_entries=100000, iterable=True)
     async def get_users_in_room(self, room_id: str) -> List[str]:
         return await self.db_pool.runInteraction(
             "get_users_in_room", self.get_users_in_room_txn, room_id
@@ -281,6 +283,9 @@ class RoomMemberWorkerStore(EventsWorkerStore):
 
         Returns:
             A mapping from user ID to ProfileInfo.
+
+        Preconditions:
+          - There is full state available for the room (it is not partial-stated).
         """
 
         def _get_users_in_room_with_profiles(
@@ -561,7 +566,7 @@ class RoomMemberWorkerStore(EventsWorkerStore):
 
         return results_dict.get("membership"), results_dict.get("event_id")
 
-    @cached(max_entries=500000, iterable=True, prune_unread_entries=False)
+    @cached(max_entries=500000, iterable=True)
     async def get_rooms_for_user_with_stream_ordering(
         self, user_id: str
     ) -> FrozenSet[GetRoomsForUserWithStreamOrdering]:
@@ -732,25 +737,76 @@ class RoomMemberWorkerStore(EventsWorkerStore):
         )
         return frozenset(r.room_id for r in rooms)
 
-    @cached(
-        max_entries=500000,
-        cache_context=True,
-        iterable=True,
-        prune_unread_entries=False,
+    @cached(max_entries=10000)
+    async def does_pair_of_users_share_a_room(
+        self, user_id: str, other_user_id: str
+    ) -> bool:
+        raise NotImplementedError()
+
+    @cachedList(
+        cached_method_name="does_pair_of_users_share_a_room", list_name="other_user_ids"
     )
-    async def get_users_who_share_room_with_user(
-        self, user_id: str, cache_context: _CacheContext
+    async def _do_users_share_a_room(
+        self, user_id: str, other_user_ids: Collection[str]
+    ) -> Mapping[str, Optional[bool]]:
+        """Return mapping from user ID to whether they share a room with the
+        given user.
+
+        Note: `None` and `False` are equivalent and mean they don't share a
+        room.
+        """
+
+        def do_users_share_a_room_txn(
+            txn: LoggingTransaction, user_ids: Collection[str]
+        ) -> Dict[str, bool]:
+            clause, args = make_in_list_sql_clause(
+                self.database_engine, "state_key", user_ids
+            )
+
+            # This query works by fetching both the list of rooms for the target
+            # user and the set of other users, and then checking if there is any
+            # overlap.
+            sql = f"""
+                SELECT b.state_key
+                FROM (
+                    SELECT room_id FROM current_state_events
+                    WHERE type = 'm.room.member' AND membership = 'join' AND state_key = ?
+                ) AS a
+                INNER JOIN (
+                    SELECT room_id, state_key FROM current_state_events
+                    WHERE type = 'm.room.member' AND membership = 'join' AND {clause}
+                ) AS b using (room_id)
+                LIMIT 1
+            """
+
+            txn.execute(sql, (user_id, *args))
+            return {u: True for u, in txn}
+
+        to_return = {}
+        for batch_user_ids in batch_iter(other_user_ids, 1000):
+            res = await self.db_pool.runInteraction(
+                "do_users_share_a_room", do_users_share_a_room_txn, batch_user_ids
+            )
+            to_return.update(res)
+
+        return to_return
+
+    async def do_users_share_a_room(
+        self, user_id: str, other_user_ids: Collection[str]
     ) -> Set[str]:
+        """Return the set of users who share a room with the first users"""
+
+        user_dict = await self._do_users_share_a_room(user_id, other_user_ids)
+
+        return {u for u, share_room in user_dict.items() if share_room}
+
+    async def get_users_who_share_room_with_user(self, user_id: str) -> Set[str]:
         """Returns the set of users who share a room with `user_id`"""
-        room_ids = await self.get_rooms_for_user(
-            user_id, on_invalidate=cache_context.invalidate
-        )
+        room_ids = await self.get_rooms_for_user(user_id)
 
         user_who_share_room = set()
         for room_id in room_ids:
-            user_ids = await self.get_users_in_room(
-                room_id, on_invalidate=cache_context.invalidate
-            )
+            user_ids = await self.get_users_in_room(room_id)
             user_who_share_room.update(user_ids)
 
         return user_who_share_room
@@ -779,9 +835,9 @@ class RoomMemberWorkerStore(EventsWorkerStore):
 
         return shared_room_ids or frozenset()
 
-    async def get_joined_users_from_state(
+    async def get_joined_user_ids_from_state(
         self, room_id: str, state: StateMap[str], state_entry: "_StateCacheEntry"
-    ) -> Dict[str, ProfileInfo]:
+    ) -> Set[str]:
         state_group: Union[object, int] = state_entry.state_group
         if not state_group:
             # If state_group is None it means it has yet to be assigned a
@@ -792,25 +848,25 @@ class RoomMemberWorkerStore(EventsWorkerStore):
 
         assert state_group is not None
         with Measure(self._clock, "get_joined_users_from_state"):
-            return await self._get_joined_users_from_context(
+            return await self._get_joined_user_ids_from_context(
                 room_id, state_group, state, context=state_entry
             )
 
     @cached(num_args=2, iterable=True, max_entries=100000)
-    async def _get_joined_users_from_context(
+    async def _get_joined_user_ids_from_context(
         self,
         room_id: str,
         state_group: Union[object, int],
         current_state_ids: StateMap[str],
         event: Optional[EventBase] = None,
         context: Optional["_StateCacheEntry"] = None,
-    ) -> Dict[str, ProfileInfo]:
+    ) -> Set[str]:
         # We don't use `state_group`, it's there so that we can cache based
         # on it. However, it's important that it's never None, since two current_states
         # with a state_group of None are likely to be different.
         assert state_group is not None
 
-        users_in_room = {}
+        users_in_room = set()
         member_event_ids = [
             e_id
             for key, e_id in current_state_ids.items()
@@ -823,11 +879,11 @@ class RoomMemberWorkerStore(EventsWorkerStore):
             # If we do then we can reuse that result and simply update it with
             # any membership changes in `delta_ids`
             if context.prev_group and context.delta_ids:
-                prev_res = self._get_joined_users_from_context.cache.get_immediate(
+                prev_res = self._get_joined_user_ids_from_context.cache.get_immediate(
                     (room_id, context.prev_group), None
                 )
-                if prev_res and isinstance(prev_res, dict):
-                    users_in_room = dict(prev_res)
+                if prev_res and isinstance(prev_res, set):
+                    users_in_room = prev_res
                     member_event_ids = [
                         e_id
                         for key, e_id in context.delta_ids.items()
@@ -835,7 +891,7 @@ class RoomMemberWorkerStore(EventsWorkerStore):
                     ]
                     for etype, state_key in context.delta_ids:
                         if etype == EventTypes.Member:
-                            users_in_room.pop(state_key, None)
+                            users_in_room.discard(state_key)
 
         # We check if we have any of the member event ids in the event cache
         # before we ask the DB
@@ -843,7 +899,7 @@ class RoomMemberWorkerStore(EventsWorkerStore):
         # We don't update the event cache hit ratio as it completely throws off
         # the hit ratio counts. After all, we don't populate the cache if we
         # miss it here
-        event_map = await self._get_events_from_cache(
+        event_map = self._get_events_from_local_cache(
             member_event_ids, update_metrics=False
         )
 
@@ -852,71 +908,64 @@ class RoomMemberWorkerStore(EventsWorkerStore):
             ev_entry = event_map.get(event_id)
             if ev_entry and not ev_entry.event.rejected_reason:
                 if ev_entry.event.membership == Membership.JOIN:
-                    users_in_room[ev_entry.event.state_key] = ProfileInfo(
-                        display_name=ev_entry.event.content.get("displayname", None),
-                        avatar_url=ev_entry.event.content.get("avatar_url", None),
-                    )
+                    users_in_room.add(ev_entry.event.state_key)
             else:
                 missing_member_event_ids.append(event_id)
 
         if missing_member_event_ids:
-            event_to_memberships = await self._get_joined_profiles_from_event_ids(
+            event_to_memberships = await self._get_user_ids_from_membership_event_ids(
                 missing_member_event_ids
             )
-            users_in_room.update(row for row in event_to_memberships.values() if row)
+            users_in_room.update(
+                user_id for user_id in event_to_memberships.values() if user_id
+            )
 
         if event is not None and event.type == EventTypes.Member:
             if event.membership == Membership.JOIN:
                 if event.event_id in member_event_ids:
-                    users_in_room[event.state_key] = ProfileInfo(
-                        display_name=event.content.get("displayname", None),
-                        avatar_url=event.content.get("avatar_url", None),
-                    )
+                    users_in_room.add(event.state_key)
 
         return users_in_room
 
-    @cached(max_entries=10000)
-    def _get_joined_profile_from_event_id(
+    @cached(
+        max_entries=10000,
+        # This name matches the old function that has been replaced - the cache name
+        # is kept here to maintain backwards compatibility.
+        name="_get_joined_profile_from_event_id",
+    )
+    def _get_user_id_from_membership_event_id(
         self, event_id: str
     ) -> Optional[Tuple[str, ProfileInfo]]:
         raise NotImplementedError()
 
     @cachedList(
-        cached_method_name="_get_joined_profile_from_event_id",
+        cached_method_name="_get_user_id_from_membership_event_id",
         list_name="event_ids",
     )
-    async def _get_joined_profiles_from_event_ids(
+    async def _get_user_ids_from_membership_event_ids(
         self, event_ids: Iterable[str]
-    ) -> Dict[str, Optional[Tuple[str, ProfileInfo]]]:
+    ) -> Dict[str, Optional[str]]:
         """For given set of member event_ids check if they point to a join
-        event and if so return the associated user and profile info.
+        event.
 
         Args:
             event_ids: The member event IDs to lookup
 
         Returns:
-            Map from event ID to `user_id` and ProfileInfo (or None if not join event).
+            Map from event ID to `user_id`, or None if event is not a join.
         """
 
         rows = await self.db_pool.simple_select_many_batch(
             table="room_memberships",
             column="event_id",
             iterable=event_ids,
-            retcols=("user_id", "display_name", "avatar_url", "event_id"),
+            retcols=("user_id", "event_id"),
             keyvalues={"membership": Membership.JOIN},
             batch_size=1000,
-            desc="_get_joined_profiles_from_event_ids",
+            desc="_get_user_ids_from_membership_event_ids",
         )
 
-        return {
-            row["event_id"]: (
-                row["user_id"],
-                ProfileInfo(
-                    avatar_url=row["avatar_url"], display_name=row["display_name"]
-                ),
-            )
-            for row in rows
-        }
+        return {row["event_id"]: row["user_id"] for row in rows}
 
     @cached(max_entries=10000)
     async def is_host_joined(self, room_id: str, host: str) -> bool:
@@ -1075,12 +1124,12 @@ class RoomMemberWorkerStore(EventsWorkerStore):
             else:
                 # The cache doesn't match the state group or prev state group,
                 # so we calculate the result from first principles.
-                joined_users = await self.get_joined_users_from_state(
+                joined_user_ids = await self.get_joined_user_ids_from_state(
                     room_id, state, state_entry
                 )
 
                 cache.hosts_to_joined_users = {}
-                for user_id in joined_users:
+                for user_id in joined_user_ids:
                     host = intern_string(get_domain_from_id(user_id))
                     cache.hosts_to_joined_users.setdefault(host, set()).add(user_id)
 
@@ -1159,6 +1208,30 @@ class RoomMemberWorkerStore(EventsWorkerStore):
             "get_forgotten_rooms_for_user", _get_forgotten_rooms_for_user_txn
         )
 
+    async def is_locally_forgotten_room(self, room_id: str) -> bool:
+        """Returns whether all local users have forgotten this room_id.
+
+        Args:
+            room_id: The room ID to query.
+
+        Returns:
+            Whether the room is forgotten.
+        """
+
+        sql = """
+            SELECT count(*) > 0 FROM local_current_membership
+            INNER JOIN room_memberships USING (room_id, event_id)
+            WHERE
+                room_id = ?
+                AND forgotten = 0;
+        """
+
+        rows = await self.db_pool.execute("is_forgotten_room", None, sql, room_id)
+
+        # `count(*)` returns always an integer
+        # If any rows still exist it means someone has not forgotten this room yet
+        return not rows[0][0]
+
     async def get_rooms_user_has_been_in(self, user_id: str) -> Set[str]:
         """Get all rooms that the user has ever been in.
 
diff --git a/synapse/storage/databases/main/state.py b/synapse/storage/databases/main/state.py
index 9674c4a757..0b10af0e58 100644
--- a/synapse/storage/databases/main/state.py
+++ b/synapse/storage/databases/main/state.py
@@ -419,15 +419,22 @@ class StateGroupWorkerStore(EventsWorkerStore, SQLBaseStore):
         # anything that was rejected should have the same state as its
         # predecessor.
         if context.rejected:
-            assert context.state_group == context.state_group_before_event
+            state_group = context.state_group_before_event
+        else:
+            state_group = context.state_group
 
         self.db_pool.simple_update_txn(
             txn,
             table="event_to_state_groups",
             keyvalues={"event_id": event.event_id},
-            updatevalues={"state_group": context.state_group},
+            updatevalues={"state_group": state_group},
         )
 
+        # the event may now be rejected where it was not before, or vice versa,
+        # in which case we need to update the rejected flags.
+        if bool(context.rejected) != (event.rejected_reason is not None):
+            self.mark_event_rejected_txn(txn, event.event_id, context.rejected)
+
         self.db_pool.simple_delete_one_txn(
             txn,
             table="partial_state_events",
@@ -440,7 +447,7 @@ class StateGroupWorkerStore(EventsWorkerStore, SQLBaseStore):
         txn.call_after(
             self._get_state_group_for_event.prefill,
             (event.event_id,),
-            context.state_group,
+            state_group,
         )
 
 
diff --git a/synapse/storage/databases/main/stream.py b/synapse/storage/databases/main/stream.py
index 2590b52f73..a347430aa7 100644
--- a/synapse/storage/databases/main/stream.py
+++ b/synapse/storage/databases/main/stream.py
@@ -58,6 +58,7 @@ from twisted.internet import defer
 from synapse.api.filtering import Filter
 from synapse.events import EventBase
 from synapse.logging.context import make_deferred_yieldable, run_in_background
+from synapse.logging.opentracing import trace
 from synapse.storage._base import SQLBaseStore
 from synapse.storage.database import (
     DatabasePool,
@@ -1346,6 +1347,7 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
 
         return rows, next_token
 
+    @trace
     async def paginate_room_events(
         self,
         room_id: str,
diff --git a/synapse/storage/databases/state/store.py b/synapse/storage/databases/state/store.py
index afbc85ad0c..bb64543c1f 100644
--- a/synapse/storage/databases/state/store.py
+++ b/synapse/storage/databases/state/store.py
@@ -202,7 +202,14 @@ class StateGroupDataStore(StateBackgroundUpdateStore, SQLBaseStore):
                 requests state from the cache, if False we need to query the DB for the
                 missing state.
         """
-        cache_entry = cache.get(group)
+        # If we are asked explicitly for a subset of keys, we only ask for those
+        # from the cache. This ensures that the `DictionaryCache` can make
+        # better decisions about what to cache and what to expire.
+        dict_keys = None
+        if not state_filter.has_wildcards():
+            dict_keys = state_filter.concrete_types()
+
+        cache_entry = cache.get(group, dict_keys=dict_keys)
         state_dict_ids = cache_entry.value
 
         if cache_entry.full or state_filter.is_full():
diff --git a/synapse/storage/state.py b/synapse/storage/state.py
index af3bab2c15..0004d955b4 100644
--- a/synapse/storage/state.py
+++ b/synapse/storage/state.py
@@ -539,15 +539,6 @@ class StateFilter:
             is_mine_id: a callable which confirms if a given state_key matches a mxid
                of a local user
         """
-
-        # TODO(faster_joins): it's not entirely clear that this is safe. In particular,
-        #  there may be circumstances in which we return a piece of state that, once we
-        #  resync the state, we discover is invalid. For example: if it turns out that
-        #  the sender of a piece of state wasn't actually in the room, then clearly that
-        #  state shouldn't have been returned.
-        #  We should at least add some tests around this to see what happens.
-        #  https://github.com/matrix-org/synapse/issues/13006
-
         # if we haven't requested membership events, then it depends on the value of
         # 'include_others'
         if EventTypes.Member not in self.types:
diff --git a/synapse/storage/util/partial_state_events_tracker.py b/synapse/storage/util/partial_state_events_tracker.py
index 466e5137f2..b4bf49dace 100644
--- a/synapse/storage/util/partial_state_events_tracker.py
+++ b/synapse/storage/util/partial_state_events_tracker.py
@@ -20,6 +20,7 @@ from twisted.internet import defer
 from twisted.internet.defer import Deferred
 
 from synapse.logging.context import PreserveLoggingContext, make_deferred_yieldable
+from synapse.logging.opentracing import trace_with_opname
 from synapse.storage.databases.main.events_worker import EventsWorkerStore
 from synapse.storage.databases.main.room import RoomWorkerStore
 from synapse.util import unwrapFirstError
@@ -58,6 +59,7 @@ class PartialStateEventsTracker:
             for o in observers:
                 o.callback(None)
 
+    @trace_with_opname("PartialStateEventsTracker.await_full_state")
     async def await_full_state(self, event_ids: Collection[str]) -> None:
         """Wait for all the given events to have full state.
 
@@ -151,6 +153,7 @@ class PartialCurrentStateTracker:
             for o in observers:
                 o.callback(None)
 
+    @trace_with_opname("PartialCurrentStateTracker.await_full_state")
     async def await_full_state(self, room_id: str) -> None:
         # We add the deferred immediately so that the DB call to check for
         # partial state doesn't race when we unpartial the room.
diff --git a/synapse/streams/events.py b/synapse/streams/events.py
index 54e0b1a23b..bcd840bd88 100644
--- a/synapse/streams/events.py
+++ b/synapse/streams/events.py
@@ -21,6 +21,7 @@ from synapse.handlers.presence import PresenceEventSource
 from synapse.handlers.receipts import ReceiptEventSource
 from synapse.handlers.room import RoomEventSource
 from synapse.handlers.typing import TypingNotificationEventSource
+from synapse.logging.opentracing import trace
 from synapse.streams import EventSource
 from synapse.types import StreamToken
 
@@ -69,6 +70,7 @@ class EventSources:
         )
         return token
 
+    @trace
     async def get_current_token_for_pagination(self, room_id: str) -> StreamToken:
         """Get the current token for a given room to be used to paginate
         events.
diff --git a/synapse/util/caches/deferred_cache.py b/synapse/util/caches/deferred_cache.py
index 1d6ec22191..6425f851ea 100644
--- a/synapse/util/caches/deferred_cache.py
+++ b/synapse/util/caches/deferred_cache.py
@@ -14,15 +14,19 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import abc
 import enum
 import threading
 from typing import (
     Callable,
+    Collection,
+    Dict,
     Generic,
-    Iterable,
     MutableMapping,
     Optional,
+    Set,
     Sized,
+    Tuple,
     TypeVar,
     Union,
     cast,
@@ -31,7 +35,6 @@ from typing import (
 from prometheus_client import Gauge
 
 from twisted.internet import defer
-from twisted.python import failure
 from twisted.python.failure import Failure
 
 from synapse.util.async_helpers import ObservableDeferred
@@ -94,7 +97,7 @@ class DeferredCache(Generic[KT, VT]):
 
         # _pending_deferred_cache maps from the key value to a `CacheEntry` object.
         self._pending_deferred_cache: Union[
-            TreeCache, "MutableMapping[KT, CacheEntry]"
+            TreeCache, "MutableMapping[KT, CacheEntry[KT, VT]]"
         ] = cache_type()
 
         def metrics_cb() -> None:
@@ -159,15 +162,16 @@ class DeferredCache(Generic[KT, VT]):
         Raises:
             KeyError if the key is not found in the cache
         """
-        callbacks = [callback] if callback else []
         val = self._pending_deferred_cache.get(key, _Sentinel.sentinel)
         if val is not _Sentinel.sentinel:
-            val.callbacks.update(callbacks)
+            val.add_invalidation_callback(key, callback)
             if update_metrics:
                 m = self.cache.metrics
                 assert m  # we always have a name, so should always have metrics
                 m.inc_hits()
-            return val.deferred.observe()
+            return val.deferred(key)
+
+        callbacks = (callback,) if callback else ()
 
         val2 = self.cache.get(
             key, _Sentinel.sentinel, callbacks=callbacks, update_metrics=update_metrics
@@ -177,6 +181,73 @@ class DeferredCache(Generic[KT, VT]):
         else:
             return defer.succeed(val2)
 
+    def get_bulk(
+        self,
+        keys: Collection[KT],
+        callback: Optional[Callable[[], None]] = None,
+    ) -> Tuple[Dict[KT, VT], Optional["defer.Deferred[Dict[KT, VT]]"], Collection[KT]]:
+        """Bulk lookup of items in the cache.
+
+        Returns:
+            A 3-tuple of:
+                1. a dict of key/value of items already cached;
+                2. a deferred that resolves to a dict of key/value of items
+                   we're already fetching; and
+                3. a collection of keys that don't appear in the previous two.
+        """
+
+        # The cached results
+        cached = {}
+
+        # List of pending deferreds
+        pending = []
+
+        # Dict that gets filled out when the pending deferreds complete
+        pending_results = {}
+
+        # List of keys that aren't in either cache
+        missing = []
+
+        callbacks = (callback,) if callback else ()
+
+        for key in keys:
+            # Check if its in the main cache.
+            immediate_value = self.cache.get(
+                key,
+                _Sentinel.sentinel,
+                callbacks=callbacks,
+            )
+            if immediate_value is not _Sentinel.sentinel:
+                cached[key] = immediate_value
+                continue
+
+            # Check if its in the pending cache
+            pending_value = self._pending_deferred_cache.get(key, _Sentinel.sentinel)
+            if pending_value is not _Sentinel.sentinel:
+                pending_value.add_invalidation_callback(key, callback)
+
+                def completed_cb(value: VT, key: KT) -> VT:
+                    pending_results[key] = value
+                    return value
+
+                # Add a callback to fill out `pending_results` when that completes
+                d = pending_value.deferred(key).addCallback(completed_cb, key)
+                pending.append(d)
+                continue
+
+            # Not in either cache
+            missing.append(key)
+
+        # If we've got pending deferreds, squash them into a single one that
+        # returns `pending_results`.
+        pending_deferred = None
+        if pending:
+            pending_deferred = defer.gatherResults(
+                pending, consumeErrors=True
+            ).addCallback(lambda _: pending_results)
+
+        return (cached, pending_deferred, missing)
+
     def get_immediate(
         self, key: KT, default: T, update_metrics: bool = True
     ) -> Union[VT, T]:
@@ -218,84 +289,89 @@ class DeferredCache(Generic[KT, VT]):
             value: a deferred which will complete with a result to add to the cache
             callback: An optional callback to be called when the entry is invalidated
         """
-        if not isinstance(value, defer.Deferred):
-            raise TypeError("not a Deferred")
-
-        callbacks = [callback] if callback else []
         self.check_thread()
 
-        existing_entry = self._pending_deferred_cache.pop(key, None)
-        if existing_entry:
-            existing_entry.invalidate()
+        self._pending_deferred_cache.pop(key, None)
 
         # XXX: why don't we invalidate the entry in `self.cache` yet?
 
-        # we can save a whole load of effort if the deferred is ready.
-        if value.called:
-            result = value.result
-            if not isinstance(result, failure.Failure):
-                self.cache.set(key, cast(VT, result), callbacks)
-            return value
-
         # otherwise, we'll add an entry to the _pending_deferred_cache for now,
         # and add callbacks to add it to the cache properly later.
+        entry = CacheEntrySingle[KT, VT](value)
+        entry.add_invalidation_callback(key, callback)
+        self._pending_deferred_cache[key] = entry
+        deferred = entry.deferred(key).addCallbacks(
+            self._completed_callback,
+            self._error_callback,
+            callbackArgs=(entry, key),
+            errbackArgs=(entry, key),
+        )
 
-        observable = ObservableDeferred(value, consumeErrors=True)
-        observer = observable.observe()
-        entry = CacheEntry(deferred=observable, callbacks=callbacks)
+        # we return a new Deferred which will be called before any subsequent observers.
+        return deferred
 
-        self._pending_deferred_cache[key] = entry
+    def start_bulk_input(
+        self,
+        keys: Collection[KT],
+        callback: Optional[Callable[[], None]] = None,
+    ) -> "CacheMultipleEntries[KT, VT]":
+        """Bulk set API for use when fetching multiple keys at once from the DB.
 
-        def compare_and_pop() -> bool:
-            """Check if our entry is still the one in _pending_deferred_cache, and
-            if so, pop it.
-
-            Returns true if the entries matched.
-            """
-            existing_entry = self._pending_deferred_cache.pop(key, None)
-            if existing_entry is entry:
-                return True
-
-            # oops, the _pending_deferred_cache has been updated since
-            # we started our query, so we are out of date.
-            #
-            # Better put back whatever we took out. (We do it this way
-            # round, rather than peeking into the _pending_deferred_cache
-            # and then removing on a match, to make the common case faster)
-            if existing_entry is not None:
-                self._pending_deferred_cache[key] = existing_entry
-
-            return False
-
-        def cb(result: VT) -> None:
-            if compare_and_pop():
-                self.cache.set(key, result, entry.callbacks)
-            else:
-                # we're not going to put this entry into the cache, so need
-                # to make sure that the invalidation callbacks are called.
-                # That was probably done when _pending_deferred_cache was
-                # updated, but it's possible that `set` was called without
-                # `invalidate` being previously called, in which case it may
-                # not have been. Either way, let's double-check now.
-                entry.invalidate()
-
-        def eb(_fail: Failure) -> None:
-            compare_and_pop()
-            entry.invalidate()
-
-        # once the deferred completes, we can move the entry from the
-        # _pending_deferred_cache to the real cache.
-        #
-        observer.addCallbacks(cb, eb)
+        Called *before* starting the fetch from the DB, and the caller *must*
+        call either `complete_bulk(..)` or `error_bulk(..)` on the return value.
+        """
 
-        # we return a new Deferred which will be called before any subsequent observers.
-        return observable.observe()
+        entry = CacheMultipleEntries[KT, VT]()
+        entry.add_global_invalidation_callback(callback)
+
+        for key in keys:
+            self._pending_deferred_cache[key] = entry
+
+        return entry
+
+    def _completed_callback(
+        self, value: VT, entry: "CacheEntry[KT, VT]", key: KT
+    ) -> VT:
+        """Called when a deferred is completed."""
+        # We check if the current entry matches the entry associated with the
+        # deferred. If they don't match then it got invalidated.
+        current_entry = self._pending_deferred_cache.pop(key, None)
+        if current_entry is not entry:
+            if current_entry:
+                self._pending_deferred_cache[key] = current_entry
+            return value
+
+        self.cache.set(key, value, entry.get_invalidation_callbacks(key))
+
+        return value
+
+    def _error_callback(
+        self,
+        failure: Failure,
+        entry: "CacheEntry[KT, VT]",
+        key: KT,
+    ) -> Failure:
+        """Called when a deferred errors."""
+
+        # We check if the current entry matches the entry associated with the
+        # deferred. If they don't match then it got invalidated.
+        current_entry = self._pending_deferred_cache.pop(key, None)
+        if current_entry is not entry:
+            if current_entry:
+                self._pending_deferred_cache[key] = current_entry
+            return failure
+
+        for cb in entry.get_invalidation_callbacks(key):
+            cb()
+
+        return failure
 
     def prefill(
         self, key: KT, value: VT, callback: Optional[Callable[[], None]] = None
     ) -> None:
-        callbacks = [callback] if callback else []
+        callbacks = (callback,) if callback else ()
         self.cache.set(key, value, callbacks=callbacks)
+        self._pending_deferred_cache.pop(key, None)
 
     def invalidate(self, key: KT) -> None:
         """Delete a key, or tree of entries
@@ -311,41 +387,129 @@ class DeferredCache(Generic[KT, VT]):
         self.cache.del_multi(key)
 
         # if we have a pending lookup for this key, remove it from the
-        # _pending_deferred_cache, which will (a) stop it being returned
-        # for future queries and (b) stop it being persisted as a proper entry
+        # _pending_deferred_cache, which will (a) stop it being returned for
+        # future queries and (b) stop it being persisted as a proper entry
         # in self.cache.
         entry = self._pending_deferred_cache.pop(key, None)
-
-        # run the invalidation callbacks now, rather than waiting for the
-        # deferred to resolve.
         if entry:
             # _pending_deferred_cache.pop should either return a CacheEntry, or, in the
             # case of a TreeCache, a dict of keys to cache entries. Either way calling
             # iterate_tree_cache_entry on it will do the right thing.
             for entry in iterate_tree_cache_entry(entry):
-                entry.invalidate()
+                for cb in entry.get_invalidation_callbacks(key):
+                    cb()
 
     def invalidate_all(self) -> None:
         self.check_thread()
         self.cache.clear()
-        for entry in self._pending_deferred_cache.values():
-            entry.invalidate()
+        for key, entry in self._pending_deferred_cache.items():
+            for cb in entry.get_invalidation_callbacks(key):
+                cb()
+
         self._pending_deferred_cache.clear()
 
 
-class CacheEntry:
-    __slots__ = ["deferred", "callbacks", "invalidated"]
+class CacheEntry(Generic[KT, VT], metaclass=abc.ABCMeta):
+    """Abstract class for entries in `DeferredCache[KT, VT]`"""
 
-    def __init__(
-        self, deferred: ObservableDeferred, callbacks: Iterable[Callable[[], None]]
-    ):
-        self.deferred = deferred
-        self.callbacks = set(callbacks)
-        self.invalidated = False
-
-    def invalidate(self) -> None:
-        if not self.invalidated:
-            self.invalidated = True
-            for callback in self.callbacks:
-                callback()
-            self.callbacks.clear()
+    @abc.abstractmethod
+    def deferred(self, key: KT) -> "defer.Deferred[VT]":
+        """Get a deferred that a caller can wait on to get the value at the
+        given key"""
+        ...
+
+    @abc.abstractmethod
+    def add_invalidation_callback(
+        self, key: KT, callback: Optional[Callable[[], None]]
+    ) -> None:
+        """Add an invalidation callback"""
+        ...
+
+    @abc.abstractmethod
+    def get_invalidation_callbacks(self, key: KT) -> Collection[Callable[[], None]]:
+        """Get all invalidation callbacks"""
+        ...
+
+
+class CacheEntrySingle(CacheEntry[KT, VT]):
+    """An implementation of `CacheEntry` wrapping a deferred that results in a
+    single cache entry.
+    """
+
+    __slots__ = ["_deferred", "_callbacks"]
+
+    def __init__(self, deferred: "defer.Deferred[VT]") -> None:
+        self._deferred = ObservableDeferred(deferred, consumeErrors=True)
+        self._callbacks: Set[Callable[[], None]] = set()
+
+    def deferred(self, key: KT) -> "defer.Deferred[VT]":
+        return self._deferred.observe()
+
+    def add_invalidation_callback(
+        self, key: KT, callback: Optional[Callable[[], None]]
+    ) -> None:
+        if callback is None:
+            return
+
+        self._callbacks.add(callback)
+
+    def get_invalidation_callbacks(self, key: KT) -> Collection[Callable[[], None]]:
+        return self._callbacks
+
+
+class CacheMultipleEntries(CacheEntry[KT, VT]):
+    """Cache entry that is used for bulk lookups and insertions."""
+
+    __slots__ = ["_deferred", "_callbacks", "_global_callbacks"]
+
+    def __init__(self) -> None:
+        self._deferred: Optional[ObservableDeferred[Dict[KT, VT]]] = None
+        self._callbacks: Dict[KT, Set[Callable[[], None]]] = {}
+        self._global_callbacks: Set[Callable[[], None]] = set()
+
+    def deferred(self, key: KT) -> "defer.Deferred[VT]":
+        if not self._deferred:
+            self._deferred = ObservableDeferred(defer.Deferred(), consumeErrors=True)
+        return self._deferred.observe().addCallback(lambda res: res.get(key))
+
+    def add_invalidation_callback(
+        self, key: KT, callback: Optional[Callable[[], None]]
+    ) -> None:
+        if callback is None:
+            return
+
+        self._callbacks.setdefault(key, set()).add(callback)
+
+    def get_invalidation_callbacks(self, key: KT) -> Collection[Callable[[], None]]:
+        return self._callbacks.get(key, set()) | self._global_callbacks
+
+    def add_global_invalidation_callback(
+        self, callback: Optional[Callable[[], None]]
+    ) -> None:
+        """Add a callback for when any keys get invalidated."""
+        if callback is None:
+            return
+
+        self._global_callbacks.add(callback)
+
+    def complete_bulk(
+        self,
+        cache: DeferredCache[KT, VT],
+        result: Dict[KT, VT],
+    ) -> None:
+        """Called when there is a result"""
+        for key, value in result.items():
+            cache._completed_callback(value, self, key)
+
+        if self._deferred:
+            self._deferred.callback(result)
+
+    def error_bulk(
+        self, cache: DeferredCache[KT, VT], keys: Collection[KT], failure: Failure
+    ) -> None:
+        """Called when bulk lookup failed."""
+        for key in keys:
+            cache._error_callback(failure, self, key)
+
+        if self._deferred:
+            self._deferred.errback(failure)
diff --git a/synapse/util/caches/descriptors.py b/synapse/util/caches/descriptors.py
index 867f315b2a..10aff4d04a 100644
--- a/synapse/util/caches/descriptors.py
+++ b/synapse/util/caches/descriptors.py
@@ -25,6 +25,7 @@ from typing import (
     Generic,
     Hashable,
     Iterable,
+    List,
     Mapping,
     Optional,
     Sequence,
@@ -73,8 +74,10 @@ class _CacheDescriptorBase:
         num_args: Optional[int],
         uncached_args: Optional[Collection[str]] = None,
         cache_context: bool = False,
+        name: Optional[str] = None,
     ):
         self.orig = orig
+        self.name = name or orig.__name__
 
         arg_spec = inspect.getfullargspec(orig)
         all_args = arg_spec.args
@@ -211,7 +214,7 @@ class LruCacheDescriptor(_CacheDescriptorBase):
 
     def __get__(self, obj: Optional[Any], owner: Optional[Type]) -> Callable[..., Any]:
         cache: LruCache[CacheKey, Any] = LruCache(
-            cache_name=self.orig.__name__,
+            cache_name=self.name,
             max_size=self.max_entries,
         )
 
@@ -241,7 +244,7 @@ class LruCacheDescriptor(_CacheDescriptorBase):
 
         wrapped = cast(_CachedFunction, _wrapped)
         wrapped.cache = cache
-        obj.__dict__[self.orig.__name__] = wrapped
+        obj.__dict__[self.name] = wrapped
 
         return wrapped
 
@@ -301,12 +304,14 @@ class DeferredCacheDescriptor(_CacheDescriptorBase):
         cache_context: bool = False,
         iterable: bool = False,
         prune_unread_entries: bool = True,
+        name: Optional[str] = None,
     ):
         super().__init__(
             orig,
             num_args=num_args,
             uncached_args=uncached_args,
             cache_context=cache_context,
+            name=name,
         )
 
         if tree and self.num_args < 2:
@@ -321,7 +326,7 @@ class DeferredCacheDescriptor(_CacheDescriptorBase):
 
     def __get__(self, obj: Optional[Any], owner: Optional[Type]) -> Callable[..., Any]:
         cache: DeferredCache[CacheKey, Any] = DeferredCache(
-            name=self.orig.__name__,
+            name=self.name,
             max_entries=self.max_entries,
             tree=self.tree,
             iterable=self.iterable,
@@ -372,7 +377,7 @@ class DeferredCacheDescriptor(_CacheDescriptorBase):
         wrapped.cache = cache
         wrapped.num_args = self.num_args
 
-        obj.__dict__[self.orig.__name__] = wrapped
+        obj.__dict__[self.name] = wrapped
 
         return wrapped
 
@@ -393,6 +398,7 @@ class DeferredCacheListDescriptor(_CacheDescriptorBase):
         cached_method_name: str,
         list_name: str,
         num_args: Optional[int] = None,
+        name: Optional[str] = None,
     ):
         """
         Args:
@@ -403,7 +409,7 @@ class DeferredCacheListDescriptor(_CacheDescriptorBase):
                 but including list_name) to use as cache keys. Defaults to all
                 named args of the function.
         """
-        super().__init__(orig, num_args=num_args, uncached_args=None)
+        super().__init__(orig, num_args=num_args, uncached_args=None, name=name)
 
         self.list_name = list_name
 
@@ -435,16 +441,6 @@ class DeferredCacheListDescriptor(_CacheDescriptorBase):
             keyargs = [arg_dict[arg_nm] for arg_nm in self.arg_names]
             list_args = arg_dict[self.list_name]
 
-            results = {}
-
-            def update_results_dict(res: Any, arg: Hashable) -> None:
-                results[arg] = res
-
-            # list of deferreds to wait for
-            cached_defers = []
-
-            missing = set()
-
             # If the cache takes a single arg then that is used as the key,
             # otherwise a tuple is used.
             if num_args == 1:
@@ -452,6 +448,9 @@ class DeferredCacheListDescriptor(_CacheDescriptorBase):
                 def arg_to_cache_key(arg: Hashable) -> Hashable:
                     return arg
 
+                def cache_key_to_arg(key: tuple) -> Hashable:
+                    return key
+
             else:
                 keylist = list(keyargs)
 
@@ -459,58 +458,53 @@ class DeferredCacheListDescriptor(_CacheDescriptorBase):
                     keylist[self.list_pos] = arg
                     return tuple(keylist)
 
-            for arg in list_args:
-                try:
-                    res = cache.get(arg_to_cache_key(arg), callback=invalidate_callback)
-                    if not res.called:
-                        res.addCallback(update_results_dict, arg)
-                        cached_defers.append(res)
-                    else:
-                        results[arg] = res.result
-                except KeyError:
-                    missing.add(arg)
+                def cache_key_to_arg(key: tuple) -> Hashable:
+                    return key[self.list_pos]
+
+            cache_keys = [arg_to_cache_key(arg) for arg in list_args]
+            immediate_results, pending_deferred, missing = cache.get_bulk(
+                cache_keys, callback=invalidate_callback
+            )
+
+            results = {cache_key_to_arg(key): v for key, v in immediate_results.items()}
+
+            cached_defers: List["defer.Deferred[Any]"] = []
+            if pending_deferred:
+
+                def update_results(r: Dict) -> None:
+                    for k, v in r.items():
+                        results[cache_key_to_arg(k)] = v
+
+                pending_deferred.addCallback(update_results)
+                cached_defers.append(pending_deferred)
 
             if missing:
-                # we need a deferred for each entry in the list,
-                # which we put in the cache. Each deferred resolves with the
-                # relevant result for that key.
-                deferreds_map = {}
-                for arg in missing:
-                    deferred: "defer.Deferred[Any]" = defer.Deferred()
-                    deferreds_map[arg] = deferred
-                    key = arg_to_cache_key(arg)
-                    cached_defers.append(
-                        cache.set(key, deferred, callback=invalidate_callback)
-                    )
+                cache_entry = cache.start_bulk_input(missing, invalidate_callback)
 
                 def complete_all(res: Dict[Hashable, Any]) -> None:
-                    # the wrapped function has completed. It returns a dict.
-                    # We can now update our own result map, and then resolve the
-                    # observable deferreds in the cache.
-                    for e, d1 in deferreds_map.items():
-                        val = res.get(e, None)
-                        # make sure we update the results map before running the
-                        # deferreds, because as soon as we run the last deferred, the
-                        # gatherResults() below will complete and return the result
-                        # dict to our caller.
-                        results[e] = val
-                        d1.callback(val)
+                    missing_results = {}
+                    for key in missing:
+                        arg = cache_key_to_arg(key)
+                        val = res.get(arg, None)
+
+                        results[arg] = val
+                        missing_results[key] = val
+
+                    cache_entry.complete_bulk(cache, missing_results)
 
                 def errback_all(f: Failure) -> None:
-                    # the wrapped function has failed. Propagate the failure into
-                    # the cache, which will invalidate the entry, and cause the
-                    # relevant cached_deferreds to fail, which will propagate the
-                    # failure to our caller.
-                    for d1 in deferreds_map.values():
-                        d1.errback(f)
+                    cache_entry.error_bulk(cache, missing, f)
 
                 args_to_call = dict(arg_dict)
-                args_to_call[self.list_name] = missing
+                args_to_call[self.list_name] = {
+                    cache_key_to_arg(key) for key in missing
+                }
 
                 # dispatch the call, and attach the two handlers
-                defer.maybeDeferred(
+                missing_d = defer.maybeDeferred(
                     preserve_fn(self.orig), **args_to_call
                 ).addCallbacks(complete_all, errback_all)
+                cached_defers.append(missing_d)
 
             if cached_defers:
                 d = defer.gatherResults(cached_defers, consumeErrors=True).addCallbacks(
@@ -525,7 +519,7 @@ class DeferredCacheListDescriptor(_CacheDescriptorBase):
             else:
                 return defer.succeed(results)
 
-        obj.__dict__[self.orig.__name__] = wrapped
+        obj.__dict__[self.name] = wrapped
 
         return wrapped
 
@@ -577,6 +571,7 @@ def cached(
     cache_context: bool = False,
     iterable: bool = False,
     prune_unread_entries: bool = True,
+    name: Optional[str] = None,
 ) -> Callable[[F], _CachedFunction[F]]:
     func = lambda orig: DeferredCacheDescriptor(
         orig,
@@ -587,13 +582,18 @@ def cached(
         cache_context=cache_context,
         iterable=iterable,
         prune_unread_entries=prune_unread_entries,
+        name=name,
     )
 
     return cast(Callable[[F], _CachedFunction[F]], func)
 
 
 def cachedList(
-    *, cached_method_name: str, list_name: str, num_args: Optional[int] = None
+    *,
+    cached_method_name: str,
+    list_name: str,
+    num_args: Optional[int] = None,
+    name: Optional[str] = None,
 ) -> Callable[[F], _CachedFunction[F]]:
     """Creates a descriptor that wraps a function in a `DeferredCacheListDescriptor`.
 
@@ -628,6 +628,7 @@ def cachedList(
         cached_method_name=cached_method_name,
         list_name=list_name,
         num_args=num_args,
+        name=name,
     )
 
     return cast(Callable[[F], _CachedFunction[F]], func)
diff --git a/synapse/util/caches/dictionary_cache.py b/synapse/util/caches/dictionary_cache.py
index d267703df0..fa91479c97 100644
--- a/synapse/util/caches/dictionary_cache.py
+++ b/synapse/util/caches/dictionary_cache.py
@@ -14,11 +14,13 @@
 import enum
 import logging
 import threading
-from typing import Any, Dict, Generic, Iterable, Optional, Set, TypeVar
+from typing import Any, Dict, Generic, Iterable, Optional, Set, Tuple, TypeVar, Union
 
 import attr
+from typing_extensions import Literal
 
 from synapse.util.caches.lrucache import LruCache
+from synapse.util.caches.treecache import TreeCache
 
 logger = logging.getLogger(__name__)
 
@@ -33,10 +35,12 @@ DV = TypeVar("DV")
 
 # This class can't be generic because it uses slots with attrs.
 # See: https://github.com/python-attrs/attrs/issues/313
-@attr.s(slots=True, auto_attribs=True)
+@attr.s(slots=True, frozen=True, auto_attribs=True)
 class DictionaryEntry:  # should be: Generic[DKT, DV].
     """Returned when getting an entry from the cache
 
+    If `full` is true then `known_absent` will be the empty set.
+
     Attributes:
         full: Whether the cache has the full or dict or just some keys.
             If not full then not all requested keys will necessarily be present
@@ -53,20 +57,90 @@ class DictionaryEntry:  # should be: Generic[DKT, DV].
         return len(self.value)
 
 
+class _FullCacheKey(enum.Enum):
+    """The key we use to cache the full dict."""
+
+    KEY = object()
+
+
 class _Sentinel(enum.Enum):
     # defining a sentinel in this way allows mypy to correctly handle the
     # type of a dictionary lookup.
     sentinel = object()
 
 
+class _PerKeyValue(Generic[DV]):
+    """The cached value of a dictionary key. If `value` is the sentinel,
+    indicates that the requested key is known to *not* be in the full dict.
+    """
+
+    __slots__ = ["value"]
+
+    def __init__(self, value: Union[DV, Literal[_Sentinel.sentinel]]) -> None:
+        self.value = value
+
+    def __len__(self) -> int:
+        # We add a `__len__` implementation as we use this class in a cache
+        # where the values are variable length.
+        return 1
+
+
 class DictionaryCache(Generic[KT, DKT, DV]):
     """Caches key -> dictionary lookups, supporting caching partial dicts, i.e.
     fetching a subset of dictionary keys for a particular key.
+
+    This cache has two levels of key. First there is the "cache key" (of type
+    `KT`), which maps to a dict. The keys to that dict are the "dict key" (of
+    type `DKT`). The overall structure is therefore `KT->DKT->DV`. For
+    example, it might look like:
+
+       {
+           1: { 1: "a", 2: "b" },
+           2: { 1: "c" },
+       }
+
+    It is possible to look up either individual dict keys, or the *complete*
+    dict for a given cache key.
+
+    Each dict item, and the complete dict is treated as a separate LRU
+    entry for the purpose of cache expiry. For example, given:
+        dict_cache.get(1, None)  -> DictionaryEntry({1: "a", 2: "b"})
+        dict_cache.get(1, [1])  -> DictionaryEntry({1: "a"})
+        dict_cache.get(1, [2])  -> DictionaryEntry({2: "b"})
+
+    ... then the cache entry for the complete dict will expire first,
+    followed by the cache entry for the '1' dict key, and finally that
+    for the '2' dict key.
     """
 
     def __init__(self, name: str, max_entries: int = 1000):
-        self.cache: LruCache[KT, DictionaryEntry] = LruCache(
-            max_size=max_entries, cache_name=name, size_callback=len
+        # We use a single LruCache to store two different types of entries:
+        #   1. Map from (key, dict_key) -> dict value (or sentinel, indicating
+        #      the key doesn't exist in the dict); and
+        #   2. Map from (key, _FullCacheKey.KEY) -> full dict.
+        #
+        # The former is used when explicit keys of the dictionary are looked up,
+        # and the latter when the full dictionary is requested.
+        #
+        # If when explicit keys are requested and not in the cache, we then look
+        # to see if we have the full dict and use that if we do. If found in the
+        # full dict each key is added into the cache.
+        #
+        # This set up allows the `LruCache` to prune the full dict entries if
+        # they haven't been used in a while, even when there have been recent
+        # queries for subsets of the dict.
+        #
+        # Typing:
+        #     * A key of `(KT, DKT)` has a value of `_PerKeyValue`
+        #     * A key of `(KT, _FullCacheKey.KEY)` has a value of `Dict[DKT, DV]`
+        self.cache: LruCache[
+            Tuple[KT, Union[DKT, Literal[_FullCacheKey.KEY]]],
+            Union[_PerKeyValue, Dict[DKT, DV]],
+        ] = LruCache(
+            max_size=max_entries,
+            cache_name=name,
+            cache_type=TreeCache,
+            size_callback=len,
         )
 
         self.name = name
@@ -91,23 +165,83 @@ class DictionaryCache(Generic[KT, DKT, DV]):
         Args:
             key
             dict_keys: If given a set of keys then return only those keys
-                that exist in the cache.
+                that exist in the cache. If None then returns the full dict
+                if it is in the cache.
 
         Returns:
-            DictionaryEntry
+            DictionaryEntry: If `dict_keys` is not None then `DictionaryEntry`
+            will contain include the keys that are in the cache. If None then
+            will either return the full dict if in the cache, or the empty
+            dict (with `full` set to False) if it isn't.
         """
-        entry = self.cache.get(key, _Sentinel.sentinel)
-        if entry is not _Sentinel.sentinel:
-            if dict_keys is None:
-                return DictionaryEntry(
-                    entry.full, entry.known_absent, dict(entry.value)
-                )
+        if dict_keys is None:
+            # The caller wants the full set of dictionary keys for this cache key
+            return self._get_full_dict(key)
+
+        # We are being asked for a subset of keys.
+
+        # First go and check for each requested dict key in the cache, tracking
+        # which we couldn't find.
+        values = {}
+        known_absent = set()
+        missing = []
+        for dict_key in dict_keys:
+            entry = self.cache.get((key, dict_key), _Sentinel.sentinel)
+            if entry is _Sentinel.sentinel:
+                missing.append(dict_key)
+                continue
+
+            assert isinstance(entry, _PerKeyValue)
+
+            if entry.value is _Sentinel.sentinel:
+                known_absent.add(dict_key)
             else:
-                return DictionaryEntry(
-                    entry.full,
-                    entry.known_absent,
-                    {k: entry.value[k] for k in dict_keys if k in entry.value},
-                )
+                values[dict_key] = entry.value
+
+        # If we found everything we can return immediately.
+        if not missing:
+            return DictionaryEntry(False, known_absent, values)
+
+        # We are missing some keys, so check if we happen to have the full dict in
+        # the cache.
+        #
+        # We don't update the last access time for this cache fetch, as we
+        # aren't explicitly interested in the full dict and so we don't want
+        # requests for explicit dict keys to keep the full dict in the cache.
+        entry = self.cache.get(
+            (key, _FullCacheKey.KEY),
+            _Sentinel.sentinel,
+            update_last_access=False,
+        )
+        if entry is _Sentinel.sentinel:
+            # Not in the cache, return the subset of keys we found.
+            return DictionaryEntry(False, known_absent, values)
+
+        # We have the full dict!
+        assert isinstance(entry, dict)
+
+        for dict_key in missing:
+            # We explicitly add each dict key to the cache, so that cache hit
+            # rates and LRU times for each key can be tracked separately.
+            value = entry.get(dict_key, _Sentinel.sentinel)  # type: ignore[arg-type]
+            self.cache[(key, dict_key)] = _PerKeyValue(value)
+
+            if value is not _Sentinel.sentinel:
+                values[dict_key] = value
+
+        return DictionaryEntry(True, set(), values)
+
+    def _get_full_dict(
+        self,
+        key: KT,
+    ) -> DictionaryEntry:
+        """Fetch the full dict for the given key."""
+
+        # First we check if we have cached the full dict.
+        entry = self.cache.get((key, _FullCacheKey.KEY), _Sentinel.sentinel)
+        if entry is not _Sentinel.sentinel:
+            assert isinstance(entry, dict)
+            return DictionaryEntry(True, set(), entry)
 
         return DictionaryEntry(False, set(), {})
 
@@ -117,7 +251,13 @@ class DictionaryCache(Generic[KT, DKT, DV]):
         # Increment the sequence number so that any SELECT statements that
         # raced with the INSERT don't update the cache (SYN-369)
         self.sequence += 1
-        self.cache.pop(key, None)
+
+        # We want to drop all information about the dict for the given key, so
+        # we use `del_multi` to delete it all in one go.
+        #
+        # We ignore the type error here: `del_multi` accepts a truncated key
+        # (when the key type is a tuple).
+        self.cache.del_multi((key,))  # type: ignore[arg-type]
 
     def invalidate_all(self) -> None:
         self.check_thread()
@@ -131,7 +271,16 @@ class DictionaryCache(Generic[KT, DKT, DV]):
         value: Dict[DKT, DV],
         fetched_keys: Optional[Iterable[DKT]] = None,
     ) -> None:
-        """Updates the entry in the cache
+        """Updates the entry in the cache.
+
+        Note: This does *not* invalidate any existing entries for the `key`.
+        In particular, if we add an entry for the cached "full dict" with
+        `fetched_keys=None`, existing entries for individual dict keys are
+        not invalidated. Likewise, adding entries for individual keys does
+        not invalidate any cached value for the full dict.
+
+        In other words: if the underlying data is *changed*, the cache must
+        be explicitly invalidated via `.invalidate()`.
 
         Args:
             sequence
@@ -149,20 +298,27 @@ class DictionaryCache(Generic[KT, DKT, DV]):
             # Only update the cache if the caches sequence number matches the
             # number that the cache had before the SELECT was started (SYN-369)
             if fetched_keys is None:
-                self._insert(key, value, set())
+                self.cache[(key, _FullCacheKey.KEY)] = value
             else:
-                self._update_or_insert(key, value, fetched_keys)
+                self._update_subset(key, value, fetched_keys)
 
-    def _update_or_insert(
-        self, key: KT, value: Dict[DKT, DV], known_absent: Iterable[DKT]
+    def _update_subset(
+        self, key: KT, value: Dict[DKT, DV], fetched_keys: Iterable[DKT]
     ) -> None:
-        # We pop and reinsert as we need to tell the cache the size may have
-        # changed
+        """Add the given dictionary values as explicit keys in the cache.
+
+        Args:
+            key: top-level cache key
+            value: The dictionary with all the values that we should cache
+            fetched_keys: The full set of dict keys that were looked up. Any keys
+                here not in `value` should be marked as "known absent".
+        """
+
+        for dict_key, dict_value in value.items():
+            self.cache[(key, dict_key)] = _PerKeyValue(dict_value)
 
-        entry: DictionaryEntry = self.cache.pop(key, DictionaryEntry(False, set(), {}))
-        entry.value.update(value)
-        entry.known_absent.update(known_absent)
-        self.cache[key] = entry
+        for dict_key in fetched_keys:
+            if dict_key in value:
+                continue
 
-    def _insert(self, key: KT, value: Dict[DKT, DV], known_absent: Set[DKT]) -> None:
-        self.cache[key] = DictionaryEntry(True, known_absent, value)
+            self.cache[(key, dict_key)] = _PerKeyValue(_Sentinel.sentinel)
diff --git a/synapse/util/caches/lrucache.py b/synapse/util/caches/lrucache.py
index 31f41fec82..aa93109d13 100644
--- a/synapse/util/caches/lrucache.py
+++ b/synapse/util/caches/lrucache.py
@@ -25,8 +25,10 @@ from typing import (
     Collection,
     Dict,
     Generic,
+    Iterable,
     List,
     Optional,
+    Tuple,
     Type,
     TypeVar,
     Union,
@@ -44,7 +46,11 @@ from synapse.metrics.background_process_metrics import wrap_as_background_proces
 from synapse.metrics.jemalloc import get_jemalloc_stats
 from synapse.util import Clock, caches
 from synapse.util.caches import CacheMetric, EvictionReason, register_cache
-from synapse.util.caches.treecache import TreeCache, iterate_tree_cache_entry
+from synapse.util.caches.treecache import (
+    TreeCache,
+    iterate_tree_cache_entry,
+    iterate_tree_cache_items,
+)
 from synapse.util.linked_list import ListNode
 
 if TYPE_CHECKING:
@@ -537,6 +543,7 @@ class LruCache(Generic[KT, VT]):
             default: Literal[None] = None,
             callbacks: Collection[Callable[[], None]] = ...,
             update_metrics: bool = ...,
+            update_last_access: bool = ...,
         ) -> Optional[VT]:
             ...
 
@@ -546,6 +553,7 @@ class LruCache(Generic[KT, VT]):
             default: T,
             callbacks: Collection[Callable[[], None]] = ...,
             update_metrics: bool = ...,
+            update_last_access: bool = ...,
         ) -> Union[T, VT]:
             ...
 
@@ -555,10 +563,27 @@ class LruCache(Generic[KT, VT]):
             default: Optional[T] = None,
             callbacks: Collection[Callable[[], None]] = (),
             update_metrics: bool = True,
+            update_last_access: bool = True,
         ) -> Union[None, T, VT]:
+            """Look up a key in the cache
+
+            Args:
+                key
+                default
+                callbacks: A collection of callbacks that will fire when the
+                    node is removed from the cache (either due to invalidation
+                    or expiry).
+                update_metrics: Whether to update the hit rate metrics
+                update_last_access: Whether to update the last access metrics
+                    on a node if successfully fetched. These metrics are used
+                    to determine when to remove the node from the cache. Set
+                    to False if this fetch should *not* prevent a node from
+                    being expired.
+            """
             node = cache.get(key, None)
             if node is not None:
-                move_node_to_front(node)
+                if update_last_access:
+                    move_node_to_front(node)
                 node.add_callbacks(callbacks)
                 if update_metrics and metrics:
                     metrics.inc_hits()
@@ -568,6 +593,65 @@ class LruCache(Generic[KT, VT]):
                     metrics.inc_misses()
                 return default
 
+        @overload
+        def cache_get_multi(
+            key: tuple,
+            default: Literal[None] = None,
+            update_metrics: bool = True,
+        ) -> Union[None, Iterable[Tuple[KT, VT]]]:
+            ...
+
+        @overload
+        def cache_get_multi(
+            key: tuple,
+            default: T,
+            update_metrics: bool = True,
+        ) -> Union[T, Iterable[Tuple[KT, VT]]]:
+            ...
+
+        @synchronized
+        def cache_get_multi(
+            key: tuple,
+            default: Optional[T] = None,
+            update_metrics: bool = True,
+        ) -> Union[None, T, Iterable[Tuple[KT, VT]]]:
+            """Returns a generator yielding all entries under the given key.
+
+            Can only be used if backed by a tree cache.
+
+            Example:
+
+                cache = LruCache(10, cache_type=TreeCache)
+                cache[(1, 1)] = "a"
+                cache[(1, 2)] = "b"
+                cache[(2, 1)] = "c"
+
+                items = cache.get_multi((1,))
+                assert list(items) == [((1, 1), "a"), ((1, 2), "b")]
+
+            Returns:
+                Either default if the key doesn't exist, or a generator of the
+                key/value pairs.
+            """
+
+            assert isinstance(cache, TreeCache)
+
+            node = cache.get(key, None)
+            if node is not None:
+                if update_metrics and metrics:
+                    metrics.inc_hits()
+
+                # We store entries in the `TreeCache` with values of type `_Node`,
+                # which we need to unwrap.
+                return (
+                    (full_key, lru_node.value)
+                    for full_key, lru_node in iterate_tree_cache_items(key, node)
+                )
+            else:
+                if update_metrics and metrics:
+                    metrics.inc_misses()
+                return default
+
         @synchronized
         def cache_set(
             key: KT, value: VT, callbacks: Collection[Callable[[], None]] = ()
@@ -674,6 +758,8 @@ class LruCache(Generic[KT, VT]):
         self.setdefault = cache_set_default
         self.pop = cache_pop
         self.del_multi = cache_del_multi
+        if cache_type is TreeCache:
+            self.get_multi = cache_get_multi
         # `invalidate` is exposed for consistency with DeferredCache, so that it can be
         # invalidated by the cache invalidation replication stream.
         self.invalidate = cache_del_multi
@@ -748,9 +834,26 @@ class AsyncLruCache(Generic[KT, VT]):
     ) -> Optional[VT]:
         return self._lru_cache.get(key, update_metrics=update_metrics)
 
+    async def get_external(
+        self,
+        key: KT,
+        default: Optional[T] = None,
+        update_metrics: bool = True,
+    ) -> Optional[VT]:
+        # This method should fetch from any configured external cache, in this case noop.
+        return None
+
+    def get_local(
+        self, key: KT, default: Optional[T] = None, update_metrics: bool = True
+    ) -> Optional[VT]:
+        return self._lru_cache.get(key, update_metrics=update_metrics)
+
     async def set(self, key: KT, value: VT) -> None:
         self._lru_cache.set(key, value)
 
+    def set_local(self, key: KT, value: VT) -> None:
+        self._lru_cache.set(key, value)
+
     async def invalidate(self, key: KT) -> None:
         # This method should invalidate any external cache and then invalidate the LruCache.
         return self._lru_cache.invalidate(key)
diff --git a/synapse/util/caches/treecache.py b/synapse/util/caches/treecache.py
index e78305f787..fec31da2b6 100644
--- a/synapse/util/caches/treecache.py
+++ b/synapse/util/caches/treecache.py
@@ -64,6 +64,15 @@ class TreeCache:
         self.size += 1
 
     def get(self, key, default=None):
+        """When `key` is a full key, fetches the value for the given key (if
+        any).
+
+        If `key` is only a partial key (i.e. a truncated tuple) then returns a
+        `TreeCacheNode`, which can be passed to the `iterate_tree_cache_*`
+        functions to iterate over all entries in the cache with keys that start
+        with the given partial key.
+        """
+
         node = self.root
         for k in key[:-1]:
             node = node.get(k, None)
@@ -126,6 +135,9 @@ class TreeCache:
     def values(self):
         return iterate_tree_cache_entry(self.root)
 
+    def items(self):
+        return iterate_tree_cache_items((), self.root)
+
     def __len__(self) -> int:
         return self.size
 
@@ -139,3 +151,32 @@ def iterate_tree_cache_entry(d):
             yield from iterate_tree_cache_entry(value_d)
     else:
         yield d
+
+
+def iterate_tree_cache_items(key, value):
+    """Helper function to iterate over the leaves of a tree, i.e. a dict of that
+    can contain dicts.
+
+    The provided key is a tuple that will get prepended to the returned keys.
+
+    Example:
+
+        cache = TreeCache()
+        cache[(1, 1)] = "a"
+        cache[(1, 2)] = "b"
+        cache[(2, 1)] = "c"
+
+        tree_node = cache.get((1,))
+
+        items = iterate_tree_cache_items((1,), tree_node)
+        assert list(items) == [((1, 1), "a"), ((1, 2), "b")]
+
+    Returns:
+        A generator yielding key/value pairs.
+    """
+    if isinstance(value, TreeCacheNode):
+        for sub_key, sub_value in value.items():
+            yield from iterate_tree_cache_items((*key, sub_key), sub_value)
+    else:
+        # we've reached a leaf of the tree.
+        yield key, value
diff --git a/synapse/util/ratelimitutils.py b/synapse/util/ratelimitutils.py
index dfe628c97e..f678b52cb4 100644
--- a/synapse/util/ratelimitutils.py
+++ b/synapse/util/ratelimitutils.py
@@ -18,15 +18,19 @@ import logging
 import typing
 from typing import Any, DefaultDict, Iterator, List, Set
 
+from prometheus_client.core import Counter
+
 from twisted.internet import defer
 
 from synapse.api.errors import LimitExceededError
-from synapse.config.ratelimiting import FederationRateLimitConfig
+from synapse.config.ratelimiting import FederationRatelimitSettings
 from synapse.logging.context import (
     PreserveLoggingContext,
     make_deferred_yieldable,
     run_in_background,
 )
+from synapse.logging.opentracing import start_active_span
+from synapse.metrics import Histogram, LaterGauge
 from synapse.util import Clock
 
 if typing.TYPE_CHECKING:
@@ -35,8 +39,34 @@ if typing.TYPE_CHECKING:
 logger = logging.getLogger(__name__)
 
 
+# Track how much the ratelimiter is affecting requests
+rate_limit_sleep_counter = Counter("synapse_rate_limit_sleep", "")
+rate_limit_reject_counter = Counter("synapse_rate_limit_reject", "")
+queue_wait_timer = Histogram(
+    "synapse_rate_limit_queue_wait_time_seconds",
+    "sec",
+    [],
+    buckets=(
+        0.005,
+        0.01,
+        0.025,
+        0.05,
+        0.1,
+        0.25,
+        0.5,
+        0.75,
+        1.0,
+        2.5,
+        5.0,
+        10.0,
+        20.0,
+        "+Inf",
+    ),
+)
+
+
 class FederationRateLimiter:
-    def __init__(self, clock: Clock, config: FederationRateLimitConfig):
+    def __init__(self, clock: Clock, config: FederationRatelimitSettings):
         def new_limiter() -> "_PerHostRatelimiter":
             return _PerHostRatelimiter(clock=clock, config=config)
 
@@ -44,6 +74,27 @@ class FederationRateLimiter:
             str, "_PerHostRatelimiter"
         ] = collections.defaultdict(new_limiter)
 
+        # We track the number of affected hosts per time-period so we can
+        # differentiate one really noisy homeserver from a general
+        # ratelimit tuning problem across the federation.
+        LaterGauge(
+            "synapse_rate_limit_sleep_affected_hosts",
+            "Number of hosts that had requests put to sleep",
+            [],
+            lambda: sum(
+                ratelimiter.should_sleep() for ratelimiter in self.ratelimiters.values()
+            ),
+        )
+        LaterGauge(
+            "synapse_rate_limit_reject_affected_hosts",
+            "Number of hosts that had requests rejected",
+            [],
+            lambda: sum(
+                ratelimiter.should_reject()
+                for ratelimiter in self.ratelimiters.values()
+            ),
+        )
+
     def ratelimit(self, host: str) -> "_GeneratorContextManager[defer.Deferred[None]]":
         """Used to ratelimit an incoming request from a given host
 
@@ -59,11 +110,11 @@ class FederationRateLimiter:
         Returns:
             context manager which returns a deferred.
         """
-        return self.ratelimiters[host].ratelimit()
+        return self.ratelimiters[host].ratelimit(host)
 
 
 class _PerHostRatelimiter:
-    def __init__(self, clock: Clock, config: FederationRateLimitConfig):
+    def __init__(self, clock: Clock, config: FederationRatelimitSettings):
         """
         Args:
             clock
@@ -94,19 +145,42 @@ class _PerHostRatelimiter:
         self.request_times: List[int] = []
 
     @contextlib.contextmanager
-    def ratelimit(self) -> "Iterator[defer.Deferred[None]]":
+    def ratelimit(self, host: str) -> "Iterator[defer.Deferred[None]]":
         # `contextlib.contextmanager` takes a generator and turns it into a
         # context manager. The generator should only yield once with a value
         # to be returned by manager.
         # Exceptions will be reraised at the yield.
 
+        self.host = host
+
         request_id = object()
-        ret = self._on_enter(request_id)
+        # Ideally we'd use `Deferred.fromCoroutine()` here, to save on redundant
+        # type-checking, but we'd need Twisted >= 21.2.
+        ret = defer.ensureDeferred(self._on_enter_with_tracing(request_id))
         try:
             yield ret
         finally:
             self._on_exit(request_id)
 
+    def should_reject(self) -> bool:
+        """
+        Whether to reject the request if we already have too many queued up
+        (either sleeping or in the ready queue).
+        """
+        queue_size = len(self.ready_request_queue) + len(self.sleeping_requests)
+        return queue_size > self.reject_limit
+
+    def should_sleep(self) -> bool:
+        """
+        Whether to sleep the request if we already have too many requests coming
+        through within the window.
+        """
+        return len(self.request_times) > self.sleep_limit
+
+    async def _on_enter_with_tracing(self, request_id: object) -> None:
+        with start_active_span("ratelimit wait"), queue_wait_timer.time():
+            await self._on_enter(request_id)
+
     def _on_enter(self, request_id: object) -> "defer.Deferred[None]":
         time_now = self.clock.time_msec()
 
@@ -117,8 +191,9 @@ class _PerHostRatelimiter:
 
         # reject the request if we already have too many queued up (either
         # sleeping or in the ready queue).
-        queue_size = len(self.ready_request_queue) + len(self.sleeping_requests)
-        if queue_size > self.reject_limit:
+        if self.should_reject():
+            logger.debug("Ratelimiter(%s): rejecting request", self.host)
+            rate_limit_reject_counter.inc()
             raise LimitExceededError(
                 retry_after_ms=int(self.window_size / self.sleep_limit)
             )
@@ -130,7 +205,8 @@ class _PerHostRatelimiter:
                 queue_defer: defer.Deferred[None] = defer.Deferred()
                 self.ready_request_queue[request_id] = queue_defer
                 logger.info(
-                    "Ratelimiter: queueing request (queue now %i items)",
+                    "Ratelimiter(%s): queueing request (queue now %i items)",
+                    self.host,
                     len(self.ready_request_queue),
                 )
 
@@ -139,19 +215,28 @@ class _PerHostRatelimiter:
                 return defer.succeed(None)
 
         logger.debug(
-            "Ratelimit [%s]: len(self.request_times)=%d",
+            "Ratelimit(%s) [%s]: len(self.request_times)=%d",
+            self.host,
             id(request_id),
             len(self.request_times),
         )
 
-        if len(self.request_times) > self.sleep_limit:
-            logger.debug("Ratelimiter: sleeping request for %f sec", self.sleep_sec)
+        if self.should_sleep():
+            logger.debug(
+                "Ratelimiter(%s) [%s]: sleeping request for %f sec",
+                self.host,
+                id(request_id),
+                self.sleep_sec,
+            )
+            rate_limit_sleep_counter.inc()
             ret_defer = run_in_background(self.clock.sleep, self.sleep_sec)
 
             self.sleeping_requests.add(request_id)
 
             def on_wait_finished(_: Any) -> "defer.Deferred[None]":
-                logger.debug("Ratelimit [%s]: Finished sleeping", id(request_id))
+                logger.debug(
+                    "Ratelimit(%s) [%s]: Finished sleeping", self.host, id(request_id)
+                )
                 self.sleeping_requests.discard(request_id)
                 queue_defer = queue_request()
                 return queue_defer
@@ -161,7 +246,9 @@ class _PerHostRatelimiter:
             ret_defer = queue_request()
 
         def on_start(r: object) -> object:
-            logger.debug("Ratelimit [%s]: Processing req", id(request_id))
+            logger.debug(
+                "Ratelimit(%s) [%s]: Processing req", self.host, id(request_id)
+            )
             self.current_processing.add(request_id)
             return r
 
@@ -183,7 +270,7 @@ class _PerHostRatelimiter:
         return make_deferred_yieldable(ret_defer)
 
     def _on_exit(self, request_id: object) -> None:
-        logger.debug("Ratelimit [%s]: Processed req", id(request_id))
+        logger.debug("Ratelimit(%s) [%s]: Processed req", self.host, id(request_id))
         self.current_processing.discard(request_id)
         try:
             # start processing the next item on the queue.
diff --git a/synapse/visibility.py b/synapse/visibility.py
index 9abbaa5a64..c810a05907 100644
--- a/synapse/visibility.py
+++ b/synapse/visibility.py
@@ -23,6 +23,7 @@ from synapse.api.constants import EventTypes, HistoryVisibility, Membership
 from synapse.events import EventBase
 from synapse.events.snapshot import EventContext
 from synapse.events.utils import prune_event
+from synapse.logging.opentracing import trace
 from synapse.storage.controllers import StorageControllers
 from synapse.storage.databases.main import DataStore
 from synapse.storage.state import StateFilter
@@ -51,6 +52,7 @@ MEMBERSHIP_PRIORITY = (
 _HISTORY_VIS_KEY: Final[Tuple[str, str]] = (EventTypes.RoomHistoryVisibility, "")
 
 
+@trace
 async def filter_events_for_client(
     storage: StorageControllers,
     user_id: str,
@@ -71,8 +73,8 @@ async def filter_events_for_client(
           * the user is not currently a member of the room, and:
           * the user has not been a member of the room since the given
             events
-        always_include_ids: set of event ids to specifically
-            include (unless sender is ignored)
+        always_include_ids: set of event ids to specifically include, if present
+            in events (unless sender is ignored)
         filter_send_to_client: Whether we're checking an event that's going to be
             sent to a client. This might not always be the case since this function can
             also be called to check whether a user can see the state at a given point.
diff --git a/tests/api/test_auth.py b/tests/api/test_auth.py
index dfcfaf79b6..e0f363555b 100644
--- a/tests/api/test_auth.py
+++ b/tests/api/test_auth.py
@@ -284,10 +284,13 @@ class AuthTestCase(unittest.HomeserverTestCase):
             TokenLookupResult(
                 user_id="@baldrick:matrix.org",
                 device_id="device",
+                token_id=5,
                 token_owner="@admin:matrix.org",
+                token_used=True,
             )
         )
         self.store.insert_client_ip = simple_async_mock(None)
+        self.store.mark_access_token_as_used = simple_async_mock(None)
         request = Mock(args={})
         request.getClientAddress.return_value.host = "127.0.0.1"
         request.args[b"access_token"] = [self.test_token]
@@ -301,10 +304,13 @@ class AuthTestCase(unittest.HomeserverTestCase):
             TokenLookupResult(
                 user_id="@baldrick:matrix.org",
                 device_id="device",
+                token_id=5,
                 token_owner="@admin:matrix.org",
+                token_used=True,
             )
         )
         self.store.insert_client_ip = simple_async_mock(None)
+        self.store.mark_access_token_as_used = simple_async_mock(None)
         request = Mock(args={})
         request.getClientAddress.return_value.host = "127.0.0.1"
         request.args[b"access_token"] = [self.test_token]
@@ -347,7 +353,7 @@ class AuthTestCase(unittest.HomeserverTestCase):
         serialized = macaroon.serialize()
 
         user_info = self.get_success(self.auth.get_user_by_access_token(serialized))
-        self.assertEqual(user_id, user_info.user_id)
+        self.assertEqual(user_id, user_info.user.to_string())
         self.assertTrue(user_info.is_guest)
         self.store.get_user_by_id.assert_called_with(user_id)
 
diff --git a/tests/events/test_presence_router.py b/tests/events/test_presence_router.py
index ffc3012a86..685a9a6d52 100644
--- a/tests/events/test_presence_router.py
+++ b/tests/events/test_presence_router.py
@@ -141,10 +141,6 @@ class PresenceRouterTestCase(FederatingHomeserverTestCase):
         hs = self.setup_test_homeserver(
             federation_transport_client=fed_transport_client,
         )
-        # Load the modules into the homeserver
-        module_api = hs.get_module_api()
-        for module, config in hs.config.modules.loaded_modules:
-            module(config=config, api=module_api)
 
         load_legacy_presence_router(hs)
 
diff --git a/tests/federation/test_complexity.py b/tests/federation/test_complexity.py
index c6dd99316a..9f1115dd23 100644
--- a/tests/federation/test_complexity.py
+++ b/tests/federation/test_complexity.py
@@ -12,7 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from http import HTTPStatus
 from unittest.mock import Mock
 
 from synapse.api.errors import Codes, SynapseError
@@ -51,7 +50,7 @@ class RoomComplexityTests(unittest.FederatingHomeserverTestCase):
         channel = self.make_signed_federation_request(
             "GET", "/_matrix/federation/unstable/rooms/%s/complexity" % (room_1,)
         )
-        self.assertEqual(HTTPStatus.OK, channel.code)
+        self.assertEqual(200, channel.code)
         complexity = channel.json_body["v1"]
         self.assertTrue(complexity > 0, complexity)
 
@@ -63,7 +62,7 @@ class RoomComplexityTests(unittest.FederatingHomeserverTestCase):
         channel = self.make_signed_federation_request(
             "GET", "/_matrix/federation/unstable/rooms/%s/complexity" % (room_1,)
         )
-        self.assertEqual(HTTPStatus.OK, channel.code)
+        self.assertEqual(200, channel.code)
         complexity = channel.json_body["v1"]
         self.assertEqual(complexity, 1.23)
 
diff --git a/tests/federation/transport/test_knocking.py b/tests/federation/transport/test_knocking.py
index 0d048207b7..d21c11b716 100644
--- a/tests/federation/transport/test_knocking.py
+++ b/tests/federation/transport/test_knocking.py
@@ -12,7 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 from collections import OrderedDict
-from http import HTTPStatus
 from typing import Dict, List
 
 from synapse.api.constants import EventTypes, JoinRules, Membership
@@ -256,7 +255,7 @@ class FederationKnockingTestCase(
                 RoomVersions.V7.identifier,
             ),
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, channel.result)
+        self.assertEqual(200, channel.code, channel.result)
 
         # Note: We don't expect the knock membership event to be sent over federation as
         # part of the stripped room state, as the knocking homeserver already has that
@@ -294,7 +293,7 @@ class FederationKnockingTestCase(
             % (room_id, signed_knock_event.event_id),
             signed_knock_event_json,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, channel.result)
+        self.assertEqual(200, channel.code, channel.result)
 
         # Check that we got the stripped room state in return
         room_state_events = channel.json_body["knock_state_events"]
diff --git a/tests/handlers/test_deactivate_account.py b/tests/handlers/test_deactivate_account.py
index 7586e472b5..7b9b711521 100644
--- a/tests/handlers/test_deactivate_account.py
+++ b/tests/handlers/test_deactivate_account.py
@@ -11,12 +11,11 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from http import HTTPStatus
-from typing import Any, Dict
 
 from twisted.test.proto_helpers import MemoryReactor
 
 from synapse.api.constants import AccountDataTypes
+from synapse.push.baserules import PushRule
 from synapse.push.rulekinds import PRIORITY_CLASS_MAP
 from synapse.rest import admin
 from synapse.rest.client import account, login
@@ -58,7 +57,7 @@ class DeactivateAccountTestCase(HomeserverTestCase):
             access_token=self.token,
         )
 
-        self.assertEqual(req.code, HTTPStatus.OK, req)
+        self.assertEqual(req.code, 200, req)
 
     def test_global_account_data_deleted_upon_deactivation(self) -> None:
         """
@@ -131,12 +130,12 @@ class DeactivateAccountTestCase(HomeserverTestCase):
             ),
         )
 
-    def _is_custom_rule(self, push_rule: Dict[str, Any]) -> bool:
+    def _is_custom_rule(self, push_rule: PushRule) -> bool:
         """
         Default rules start with a dot: such as .m.rule and .im.vector.
         This function returns true iff a rule is custom (not default).
         """
-        return "/." not in push_rule["rule_id"]
+        return "/." not in push_rule.rule_id
 
     def test_push_rules_deleted_upon_account_deactivation(self) -> None:
         """
@@ -158,22 +157,21 @@ class DeactivateAccountTestCase(HomeserverTestCase):
         )
 
         # Test the rule exists
-        push_rules = self.get_success(self._store.get_push_rules_for_user(self.user))
+        filtered_push_rules = self.get_success(
+            self._store.get_push_rules_for_user(self.user)
+        )
         # Filter out default rules; we don't care
-        push_rules = list(filter(self._is_custom_rule, push_rules))
+        push_rules = [r for r, _ in filtered_push_rules if self._is_custom_rule(r)]
         # Check our rule made it
         self.assertEqual(
             push_rules,
             [
-                {
-                    "user_name": "@user:test",
-                    "rule_id": "personal.override.rule1",
-                    "priority_class": 5,
-                    "priority": 0,
-                    "conditions": [],
-                    "actions": [],
-                    "default": False,
-                }
+                PushRule(
+                    rule_id="personal.override.rule1",
+                    priority_class=5,
+                    conditions=[],
+                    actions=[],
+                )
             ],
             push_rules,
         )
@@ -181,9 +179,11 @@ class DeactivateAccountTestCase(HomeserverTestCase):
         # Request the deactivation of our account
         self._deactivate_my_account()
 
-        push_rules = self.get_success(self._store.get_push_rules_for_user(self.user))
+        filtered_push_rules = self.get_success(
+            self._store.get_push_rules_for_user(self.user)
+        )
         # Filter out default rules; we don't care
-        push_rules = list(filter(self._is_custom_rule, push_rules))
+        push_rules = [r for r, _ in filtered_push_rules if self._is_custom_rule(r)]
         # Check our rule no longer exists
         self.assertEqual(push_rules, [], push_rules)
 
@@ -322,3 +322,18 @@ class DeactivateAccountTestCase(HomeserverTestCase):
                 )
             ),
         )
+
+    def test_deactivate_account_needs_auth(self) -> None:
+        """
+        Tests that making a request to /deactivate with an empty body
+        succeeds in starting the user-interactive auth flow.
+        """
+        req = self.make_request(
+            "POST",
+            "account/deactivate",
+            {},
+            access_token=self.token,
+        )
+
+        self.assertEqual(req.code, 401, req)
+        self.assertEqual(req.json_body["flows"], [{"stages": ["m.login.password"]}])
diff --git a/tests/handlers/test_directory.py b/tests/handlers/test_directory.py
index 53d49ca896..3b72c4c9d0 100644
--- a/tests/handlers/test_directory.py
+++ b/tests/handlers/test_directory.py
@@ -481,17 +481,13 @@ class TestCreatePublishedRoomACL(unittest.HomeserverTestCase):
 
         return config
 
-    def prepare(
-        self, reactor: MemoryReactor, clock: Clock, hs: HomeServer
-    ) -> HomeServer:
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.allowed_user_id = self.register_user(self.allowed_localpart, "pass")
         self.allowed_access_token = self.login(self.allowed_localpart, "pass")
 
         self.denied_user_id = self.register_user("denied", "pass")
         self.denied_access_token = self.login("denied", "pass")
 
-        return hs
-
     def test_denied_without_publication_permission(self) -> None:
         """
         Try to create a room, register an alias for it, and publish it,
@@ -575,9 +571,7 @@ class TestRoomListSearchDisabled(unittest.HomeserverTestCase):
 
     servlets = [directory.register_servlets, room.register_servlets]
 
-    def prepare(
-        self, reactor: MemoryReactor, clock: Clock, hs: HomeServer
-    ) -> HomeServer:
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         room_id = self.helper.create_room_as(self.user_id)
 
         channel = self.make_request(
@@ -588,8 +582,6 @@ class TestRoomListSearchDisabled(unittest.HomeserverTestCase):
         self.room_list_handler = hs.get_room_list_handler()
         self.directory_handler = hs.get_directory_handler()
 
-        return hs
-
     def test_disabling_room_list(self) -> None:
         self.room_list_handler.enable_room_list_search = True
         self.directory_handler.enable_room_list_search = True
diff --git a/tests/handlers/test_federation.py b/tests/handlers/test_federation.py
index 8a0bb91f40..745750b1d7 100644
--- a/tests/handlers/test_federation.py
+++ b/tests/handlers/test_federation.py
@@ -14,6 +14,7 @@
 import logging
 from typing import cast
 from unittest import TestCase
+from unittest.mock import Mock, patch
 
 from twisted.test.proto_helpers import MemoryReactor
 
@@ -22,6 +23,7 @@ from synapse.api.errors import AuthError, Codes, LimitExceededError, SynapseErro
 from synapse.api.room_versions import RoomVersions
 from synapse.events import EventBase, make_event_from_dict
 from synapse.federation.federation_base import event_from_pdu_json
+from synapse.federation.federation_client import SendJoinResult
 from synapse.logging.context import LoggingContext, run_in_background
 from synapse.rest import admin
 from synapse.rest.client import login, room
@@ -30,7 +32,7 @@ from synapse.util import Clock
 from synapse.util.stringutils import random_string
 
 from tests import unittest
-from tests.test_utils import event_injection
+from tests.test_utils import event_injection, make_awaitable
 
 logger = logging.getLogger(__name__)
 
@@ -280,13 +282,21 @@ class FederationTestCase(unittest.FederatingHomeserverTestCase):
 
             # we poke this directly into _process_received_pdu, to avoid the
             # federation handler wanting to backfill the fake event.
+            state_handler = self.hs.get_state_handler()
+            context = self.get_success(
+                state_handler.compute_event_context(
+                    event,
+                    state_ids_before_event={
+                        (e.type, e.state_key): e.event_id for e in current_state
+                    },
+                    partial_state=False,
+                )
+            )
             self.get_success(
                 federation_event_handler._process_received_pdu(
                     self.OTHER_SERVER_NAME,
                     event,
-                    state_ids={
-                        (e.type, e.state_key): e.event_id for e in current_state
-                    },
+                    context,
                 )
             )
 
@@ -448,3 +458,121 @@ class EventFromPduTestCase(TestCase):
                 },
                 RoomVersions.V6,
             )
+
+
+class PartialJoinTestCase(unittest.FederatingHomeserverTestCase):
+    def test_failed_partial_join_is_clean(self) -> None:
+        """
+        Tests that, when failing to partial-join a room, we don't get stuck with
+        a partial-state flag on a room.
+        """
+
+        fed_handler = self.hs.get_federation_handler()
+        fed_client = fed_handler.federation_client
+
+        room_id = "!room:example.com"
+        membership_event = make_event_from_dict(
+            {
+                "room_id": room_id,
+                "type": "m.room.member",
+                "sender": "@alice:test",
+                "state_key": "@alice:test",
+                "content": {"membership": "join"},
+            },
+            RoomVersions.V10,
+        )
+
+        mock_make_membership_event = Mock(
+            return_value=make_awaitable(
+                (
+                    "example.com",
+                    membership_event,
+                    RoomVersions.V10,
+                )
+            )
+        )
+
+        EVENT_CREATE = make_event_from_dict(
+            {
+                "room_id": room_id,
+                "type": "m.room.create",
+                "sender": "@kristina:example.com",
+                "state_key": "",
+                "depth": 0,
+                "content": {"creator": "@kristina:example.com", "room_version": "10"},
+                "auth_events": [],
+                "origin_server_ts": 1,
+            },
+            room_version=RoomVersions.V10,
+        )
+        EVENT_CREATOR_MEMBERSHIP = make_event_from_dict(
+            {
+                "room_id": room_id,
+                "type": "m.room.member",
+                "sender": "@kristina:example.com",
+                "state_key": "@kristina:example.com",
+                "content": {"membership": "join"},
+                "depth": 1,
+                "prev_events": [EVENT_CREATE.event_id],
+                "auth_events": [EVENT_CREATE.event_id],
+                "origin_server_ts": 1,
+            },
+            room_version=RoomVersions.V10,
+        )
+        EVENT_INVITATION_MEMBERSHIP = make_event_from_dict(
+            {
+                "room_id": room_id,
+                "type": "m.room.member",
+                "sender": "@kristina:example.com",
+                "state_key": "@alice:test",
+                "content": {"membership": "invite"},
+                "depth": 2,
+                "prev_events": [EVENT_CREATOR_MEMBERSHIP.event_id],
+                "auth_events": [
+                    EVENT_CREATE.event_id,
+                    EVENT_CREATOR_MEMBERSHIP.event_id,
+                ],
+                "origin_server_ts": 1,
+            },
+            room_version=RoomVersions.V10,
+        )
+        mock_send_join = Mock(
+            return_value=make_awaitable(
+                SendJoinResult(
+                    membership_event,
+                    "example.com",
+                    state=[
+                        EVENT_CREATE,
+                        EVENT_CREATOR_MEMBERSHIP,
+                        EVENT_INVITATION_MEMBERSHIP,
+                    ],
+                    auth_chain=[
+                        EVENT_CREATE,
+                        EVENT_CREATOR_MEMBERSHIP,
+                        EVENT_INVITATION_MEMBERSHIP,
+                    ],
+                    partial_state=True,
+                    servers_in_room=["example.com"],
+                )
+            )
+        )
+
+        with patch.object(
+            fed_client, "make_membership_event", mock_make_membership_event
+        ), patch.object(fed_client, "send_join", mock_send_join):
+            # Join and check that our join event is rejected
+            # (The join event is rejected because it doesn't have any signatures)
+            join_exc = self.get_failure(
+                fed_handler.do_invite_join(["example.com"], room_id, "@alice:test", {}),
+                SynapseError,
+            )
+        self.assertIn("Join event was rejected", str(join_exc))
+
+        store = self.hs.get_datastores().main
+
+        # Check that we don't have a left-over partial_state entry.
+        self.assertFalse(
+            self.get_success(store.is_partial_state_room(room_id)),
+            f"Stale partial-stated room flag left over for {room_id} after a"
+            f" failed do_invite_join!",
+        )
diff --git a/tests/handlers/test_message.py b/tests/handlers/test_message.py
index 44da96c792..986b50ce0c 100644
--- a/tests/handlers/test_message.py
+++ b/tests/handlers/test_message.py
@@ -314,4 +314,4 @@ class ServerAclValidationTestCase(unittest.HomeserverTestCase):
         channel = self.make_request(
             "POST", path, content={}, access_token=self.access_token
         )
-        self.assertEqual(int(channel.result["code"]), 403)
+        self.assertEqual(channel.code, 403)
diff --git a/tests/handlers/test_password_providers.py b/tests/handlers/test_password_providers.py
index 4c62449c89..75934b1707 100644
--- a/tests/handlers/test_password_providers.py
+++ b/tests/handlers/test_password_providers.py
@@ -21,7 +21,6 @@ from unittest.mock import Mock
 import synapse
 from synapse.api.constants import LoginType
 from synapse.api.errors import Codes
-from synapse.handlers.auth import load_legacy_password_auth_providers
 from synapse.module_api import ModuleApi
 from synapse.rest.client import account, devices, login, logout, register
 from synapse.types import JsonDict, UserID
@@ -167,16 +166,6 @@ class PasswordAuthProviderTests(unittest.HomeserverTestCase):
         mock_password_provider.reset_mock()
         super().setUp()
 
-    def make_homeserver(self, reactor, clock):
-        hs = self.setup_test_homeserver()
-        # Load the modules into the homeserver
-        module_api = hs.get_module_api()
-        for module, config in hs.config.modules.loaded_modules:
-            module(config=config, api=module_api)
-        load_legacy_password_auth_providers(hs)
-
-        return hs
-
     @override_config(legacy_providers_config(LegacyPasswordOnlyAuthProvider))
     def test_password_only_auth_progiver_login_legacy(self):
         self.password_only_auth_provider_login_test_body()
diff --git a/tests/handlers/test_receipts.py b/tests/handlers/test_receipts.py
index a95868b5c0..5f70a2db79 100644
--- a/tests/handlers/test_receipts.py
+++ b/tests/handlers/test_receipts.py
@@ -15,6 +15,8 @@
 from copy import deepcopy
 from typing import List
 
+from parameterized import parameterized
+
 from synapse.api.constants import EduTypes, ReceiptTypes
 from synapse.types import JsonDict
 
@@ -25,13 +27,16 @@ class ReceiptsTestCase(unittest.HomeserverTestCase):
     def prepare(self, reactor, clock, hs):
         self.event_source = hs.get_event_sources().sources.receipt
 
-    def test_filters_out_private_receipt(self):
+    @parameterized.expand(
+        [ReceiptTypes.READ_PRIVATE, ReceiptTypes.UNSTABLE_READ_PRIVATE]
+    )
+    def test_filters_out_private_receipt(self, receipt_type: str) -> None:
         self._test_filters_private(
             [
                 {
                     "content": {
                         "$1435641916114394fHBLK:matrix.org": {
-                            ReceiptTypes.READ_PRIVATE: {
+                            receipt_type: {
                                 "@rikj:jki.re": {
                                     "ts": 1436451550453,
                                 }
@@ -45,13 +50,18 @@ class ReceiptsTestCase(unittest.HomeserverTestCase):
             [],
         )
 
-    def test_filters_out_private_receipt_and_ignores_rest(self):
+    @parameterized.expand(
+        [ReceiptTypes.READ_PRIVATE, ReceiptTypes.UNSTABLE_READ_PRIVATE]
+    )
+    def test_filters_out_private_receipt_and_ignores_rest(
+        self, receipt_type: str
+    ) -> None:
         self._test_filters_private(
             [
                 {
                     "content": {
                         "$1dgdgrd5641916114394fHBLK:matrix.org": {
-                            ReceiptTypes.READ_PRIVATE: {
+                            receipt_type: {
                                 "@rikj:jki.re": {
                                     "ts": 1436451550453,
                                 },
@@ -84,13 +94,18 @@ class ReceiptsTestCase(unittest.HomeserverTestCase):
             ],
         )
 
-    def test_filters_out_event_with_only_private_receipts_and_ignores_the_rest(self):
+    @parameterized.expand(
+        [ReceiptTypes.READ_PRIVATE, ReceiptTypes.UNSTABLE_READ_PRIVATE]
+    )
+    def test_filters_out_event_with_only_private_receipts_and_ignores_the_rest(
+        self, receipt_type: str
+    ) -> None:
         self._test_filters_private(
             [
                 {
                     "content": {
                         "$14356419edgd14394fHBLK:matrix.org": {
-                            ReceiptTypes.READ_PRIVATE: {
+                            receipt_type: {
                                 "@rikj:jki.re": {
                                     "ts": 1436451550453,
                                 },
@@ -125,7 +140,7 @@ class ReceiptsTestCase(unittest.HomeserverTestCase):
             ],
         )
 
-    def test_handles_empty_event(self):
+    def test_handles_empty_event(self) -> None:
         self._test_filters_private(
             [
                 {
@@ -160,13 +175,18 @@ class ReceiptsTestCase(unittest.HomeserverTestCase):
             ],
         )
 
-    def test_filters_out_receipt_event_with_only_private_receipt_and_ignores_rest(self):
+    @parameterized.expand(
+        [ReceiptTypes.READ_PRIVATE, ReceiptTypes.UNSTABLE_READ_PRIVATE]
+    )
+    def test_filters_out_receipt_event_with_only_private_receipt_and_ignores_rest(
+        self, receipt_type: str
+    ) -> None:
         self._test_filters_private(
             [
                 {
                     "content": {
                         "$14356419edgd14394fHBLK:matrix.org": {
-                            ReceiptTypes.READ_PRIVATE: {
+                            receipt_type: {
                                 "@rikj:jki.re": {
                                     "ts": 1436451550453,
                                 },
@@ -207,7 +227,7 @@ class ReceiptsTestCase(unittest.HomeserverTestCase):
             ],
         )
 
-    def test_handles_string_data(self):
+    def test_handles_string_data(self) -> None:
         """
         Tests that an invalid shape for read-receipts is handled.
         Context: https://github.com/matrix-org/synapse/issues/10603
@@ -242,13 +262,16 @@ class ReceiptsTestCase(unittest.HomeserverTestCase):
             ],
         )
 
-    def test_leaves_our_private_and_their_public(self):
+    @parameterized.expand(
+        [ReceiptTypes.READ_PRIVATE, ReceiptTypes.UNSTABLE_READ_PRIVATE]
+    )
+    def test_leaves_our_private_and_their_public(self, receipt_type: str) -> None:
         self._test_filters_private(
             [
                 {
                     "content": {
                         "$1dgdgrd5641916114394fHBLK:matrix.org": {
-                            ReceiptTypes.READ_PRIVATE: {
+                            receipt_type: {
                                 "@me:server.org": {
                                     "ts": 1436451550453,
                                 },
@@ -273,7 +296,7 @@ class ReceiptsTestCase(unittest.HomeserverTestCase):
                 {
                     "content": {
                         "$1dgdgrd5641916114394fHBLK:matrix.org": {
-                            ReceiptTypes.READ_PRIVATE: {
+                            receipt_type: {
                                 "@me:server.org": {
                                     "ts": 1436451550453,
                                 },
@@ -296,13 +319,16 @@ class ReceiptsTestCase(unittest.HomeserverTestCase):
             ],
         )
 
-    def test_we_do_not_mutate(self):
+    @parameterized.expand(
+        [ReceiptTypes.READ_PRIVATE, ReceiptTypes.UNSTABLE_READ_PRIVATE]
+    )
+    def test_we_do_not_mutate(self, receipt_type: str) -> None:
         """Ensure the input values are not modified."""
         events = [
             {
                 "content": {
                     "$1435641916114394fHBLK:matrix.org": {
-                        ReceiptTypes.READ_PRIVATE: {
+                        receipt_type: {
                             "@rikj:jki.re": {
                                 "ts": 1436451550453,
                             }
@@ -320,7 +346,7 @@ class ReceiptsTestCase(unittest.HomeserverTestCase):
 
     def _test_filters_private(
         self, events: List[JsonDict], expected_output: List[JsonDict]
-    ):
+    ) -> None:
         """Tests that the _filter_out_private returns the expected output"""
         filtered_events = self.event_source.filter_out_private_receipts(
             events, "@me:server.org"
diff --git a/tests/handlers/test_register.py b/tests/handlers/test_register.py
index 23f35d5bf5..86b3d51975 100644
--- a/tests/handlers/test_register.py
+++ b/tests/handlers/test_register.py
@@ -22,7 +22,6 @@ from synapse.api.errors import (
     ResourceLimitError,
     SynapseError,
 )
-from synapse.events.spamcheck import load_legacy_spam_checkers
 from synapse.spam_checker_api import RegistrationBehaviour
 from synapse.types import RoomAlias, RoomID, UserID, create_requester
 
@@ -144,12 +143,6 @@ class RegistrationTestCase(unittest.HomeserverTestCase):
             config=hs_config, federation_client=self.mock_federation_client
         )
 
-        load_legacy_spam_checkers(hs)
-
-        module_api = hs.get_module_api()
-        for module, config in hs.config.modules.loaded_modules:
-            module(config=config, api=module_api)
-
         return hs
 
     def prepare(self, reactor, clock, hs):
diff --git a/tests/handlers/test_room_member.py b/tests/handlers/test_room_member.py
index 254e7e4b80..1d13ed1e88 100644
--- a/tests/handlers/test_room_member.py
+++ b/tests/handlers/test_room_member.py
@@ -1,4 +1,3 @@
-from http import HTTPStatus
 from unittest.mock import Mock, patch
 
 from twisted.test.proto_helpers import MemoryReactor
@@ -15,7 +14,7 @@ from synapse.server import HomeServer
 from synapse.types import UserID, create_requester
 from synapse.util import Clock
 
-from tests.replication._base import RedisMultiWorkerStreamTestCase
+from tests.replication._base import BaseMultiWorkerStreamTestCase
 from tests.server import make_request
 from tests.test_utils import make_awaitable
 from tests.unittest import FederatingHomeserverTestCase, override_config
@@ -217,7 +216,7 @@ class TestJoinsLimitedByPerRoomRateLimiter(FederatingHomeserverTestCase):
     #   - trying to remote-join again.
 
 
-class TestReplicatedJoinsLimitedByPerRoomRateLimiter(RedisMultiWorkerStreamTestCase):
+class TestReplicatedJoinsLimitedByPerRoomRateLimiter(BaseMultiWorkerStreamTestCase):
     servlets = [
         synapse.rest.admin.register_servlets,
         synapse.rest.client.login.register_servlets,
@@ -260,7 +259,7 @@ class TestReplicatedJoinsLimitedByPerRoomRateLimiter(RedisMultiWorkerStreamTestC
             f"/_matrix/client/v3/rooms/{self.room_id}/join",
             access_token=self.bob_token,
         )
-        self.assertEqual(channel.code, HTTPStatus.OK, channel.json_body)
+        self.assertEqual(channel.code, 200, channel.json_body)
 
         # wait for join to arrive over replication
         self.replicate()
diff --git a/tests/handlers/test_send_email.py b/tests/handlers/test_send_email.py
index 6f77b1237c..da4bf8b582 100644
--- a/tests/handlers/test_send_email.py
+++ b/tests/handlers/test_send_email.py
@@ -23,7 +23,7 @@ from twisted.internet.defer import ensureDeferred
 from twisted.mail import interfaces, smtp
 
 from tests.server import FakeTransport
-from tests.unittest import HomeserverTestCase
+from tests.unittest import HomeserverTestCase, override_config
 
 
 @implementer(interfaces.IMessageDelivery)
@@ -110,3 +110,58 @@ class SendEmailHandlerTestCase(HomeserverTestCase):
         user, msg = message_delivery.messages.pop()
         self.assertEqual(str(user), "foo@bar.com")
         self.assertIn(b"Subject: test subject", msg)
+
+    @override_config(
+        {
+            "email": {
+                "notif_from": "noreply@test",
+                "force_tls": True,
+            },
+        }
+    )
+    def test_send_email_force_tls(self):
+        """Happy-path test that we can send email to an Implicit TLS server."""
+        h = self.hs.get_send_email_handler()
+        d = ensureDeferred(
+            h.send_email(
+                "foo@bar.com", "test subject", "Tests", "HTML content", "Text content"
+            )
+        )
+        # there should be an attempt to connect to localhost:465
+        self.assertEqual(len(self.reactor.sslClients), 1)
+        (
+            host,
+            port,
+            client_factory,
+            contextFactory,
+            _timeout,
+            _bindAddress,
+        ) = self.reactor.sslClients[0]
+        self.assertEqual(host, "localhost")
+        self.assertEqual(port, 465)
+
+        # wire it up to an SMTP server
+        message_delivery = _DummyMessageDelivery()
+        server_protocol = smtp.ESMTP()
+        server_protocol.delivery = message_delivery
+        # make sure that the server uses the test reactor to set timeouts
+        server_protocol.callLater = self.reactor.callLater  # type: ignore[assignment]
+
+        client_protocol = client_factory.buildProtocol(None)
+        client_protocol.makeConnection(FakeTransport(server_protocol, self.reactor))
+        server_protocol.makeConnection(
+            FakeTransport(
+                client_protocol,
+                self.reactor,
+                peer_address=IPv4Address("TCP", "127.0.0.1", 1234),
+            )
+        )
+
+        # the message should now get delivered
+        self.get_success(d, by=0.1)
+
+        # check it arrived
+        self.assertEqual(len(message_delivery.messages), 1)
+        user, msg = message_delivery.messages.pop()
+        self.assertEqual(str(user), "foo@bar.com")
+        self.assertIn(b"Subject: test subject", msg)
diff --git a/tests/handlers/test_typing.py b/tests/handlers/test_typing.py
index 7af1333126..8adba29d7f 100644
--- a/tests/handlers/test_typing.py
+++ b/tests/handlers/test_typing.py
@@ -25,7 +25,7 @@ from synapse.api.constants import EduTypes
 from synapse.api.errors import AuthError
 from synapse.federation.transport.server import TransportLayerServer
 from synapse.server import HomeServer
-from synapse.types import JsonDict, UserID, create_requester
+from synapse.types import JsonDict, Requester, UserID, create_requester
 from synapse.util import Clock
 
 from tests import unittest
@@ -117,8 +117,10 @@ class TypingNotificationsTestCase(unittest.HomeserverTestCase):
 
         self.room_members = []
 
-        async def check_user_in_room(room_id: str, user_id: str) -> None:
-            if user_id not in [u.to_string() for u in self.room_members]:
+        async def check_user_in_room(room_id: str, requester: Requester) -> None:
+            if requester.user.to_string() not in [
+                u.to_string() for u in self.room_members
+            ]:
                 raise AuthError(401, "User is not in the room")
             return None
 
diff --git a/tests/http/server/_base.py b/tests/http/server/_base.py
index 994d8880b0..5726e60cee 100644
--- a/tests/http/server/_base.py
+++ b/tests/http/server/_base.py
@@ -15,7 +15,6 @@
 import inspect
 import itertools
 import logging
-from http import HTTPStatus
 from typing import (
     Any,
     Callable,
@@ -78,7 +77,7 @@ def test_disconnect(
         if expect_cancellation:
             expected_code = HTTP_STATUS_REQUEST_CANCELLED
         else:
-            expected_code = HTTPStatus.OK
+            expected_code = 200
 
     request = channel.request
     if channel.is_finished():
diff --git a/tests/logging/test_opentracing.py b/tests/logging/test_opentracing.py
index 40148d503c..0917e478a5 100644
--- a/tests/logging/test_opentracing.py
+++ b/tests/logging/test_opentracing.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from typing import cast
+
 from twisted.internet import defer
 from twisted.test.proto_helpers import MemoryReactorClock
 
@@ -23,6 +25,8 @@ from synapse.logging.context import (
 from synapse.logging.opentracing import (
     start_active_span,
     start_active_span_follows_from,
+    tag_args,
+    trace_with_opname,
 )
 from synapse.util import Clock
 
@@ -36,10 +40,23 @@ try:
 except ImportError:
     jaeger_client = None  # type: ignore
 
+import logging
+
 from tests.unittest import TestCase
 
+logger = logging.getLogger(__name__)
+
 
 class LogContextScopeManagerTestCase(TestCase):
+    """
+    Test logging contexts and active opentracing spans.
+
+    There's casts throughout this from generic opentracing objects (e.g.
+    opentracing.Span) to the ones specific to Jaeger since they have additional
+    properties that these tests depend on. This is safe since the only supported
+    opentracing backend is Jaeger.
+    """
+
     if LogContextScopeManager is None:
         skip = "Requires opentracing"  # type: ignore[unreachable]
     if jaeger_client is None:
@@ -69,7 +86,7 @@ class LogContextScopeManagerTestCase(TestCase):
 
             # start_active_span should start and activate a span.
             scope = start_active_span("span", tracer=self._tracer)
-            span = scope.span
+            span = cast(jaeger_client.Span, scope.span)
             self.assertEqual(self._tracer.active_span, span)
             self.assertIsNotNone(span.start_time)
 
@@ -91,6 +108,7 @@ class LogContextScopeManagerTestCase(TestCase):
         with LoggingContext("root context"):
             with start_active_span("root span", tracer=self._tracer) as root_scope:
                 self.assertEqual(self._tracer.active_span, root_scope.span)
+                root_context = cast(jaeger_client.SpanContext, root_scope.span.context)
 
                 scope1 = start_active_span(
                     "child1",
@@ -99,9 +117,8 @@ class LogContextScopeManagerTestCase(TestCase):
                 self.assertEqual(
                     self._tracer.active_span, scope1.span, "child1 was not activated"
                 )
-                self.assertEqual(
-                    scope1.span.context.parent_id, root_scope.span.context.span_id
-                )
+                context1 = cast(jaeger_client.SpanContext, scope1.span.context)
+                self.assertEqual(context1.parent_id, root_context.span_id)
 
                 scope2 = start_active_span_follows_from(
                     "child2",
@@ -109,17 +126,18 @@ class LogContextScopeManagerTestCase(TestCase):
                     tracer=self._tracer,
                 )
                 self.assertEqual(self._tracer.active_span, scope2.span)
-                self.assertEqual(
-                    scope2.span.context.parent_id, scope1.span.context.span_id
-                )
+                context2 = cast(jaeger_client.SpanContext, scope2.span.context)
+                self.assertEqual(context2.parent_id, context1.span_id)
 
                 with scope1, scope2:
                     pass
 
                 # the root scope should be restored
                 self.assertEqual(self._tracer.active_span, root_scope.span)
-                self.assertIsNotNone(scope2.span.end_time)
-                self.assertIsNotNone(scope1.span.end_time)
+                span2 = cast(jaeger_client.Span, scope2.span)
+                span1 = cast(jaeger_client.Span, scope1.span)
+                self.assertIsNotNone(span2.end_time)
+                self.assertIsNotNone(span1.end_time)
 
             self.assertIsNone(self._tracer.active_span)
 
@@ -182,3 +200,80 @@ class LogContextScopeManagerTestCase(TestCase):
             self._reporter.get_spans(),
             [scopes[1].span, scopes[2].span, scopes[0].span],
         )
+
+    def test_trace_decorator_sync(self) -> None:
+        """
+        Test whether we can use `@trace_with_opname` (`@trace`) and `@tag_args`
+        with sync functions
+        """
+        with LoggingContext("root context"):
+
+            @trace_with_opname("fixture_sync_func", tracer=self._tracer)
+            @tag_args
+            def fixture_sync_func() -> str:
+                return "foo"
+
+            result = fixture_sync_func()
+            self.assertEqual(result, "foo")
+
+        # the span should have been reported
+        self.assertEqual(
+            [span.operation_name for span in self._reporter.get_spans()],
+            ["fixture_sync_func"],
+        )
+
+    def test_trace_decorator_deferred(self) -> None:
+        """
+        Test whether we can use `@trace_with_opname` (`@trace`) and `@tag_args`
+        with functions that return deferreds
+        """
+        reactor = MemoryReactorClock()
+
+        with LoggingContext("root context"):
+
+            @trace_with_opname("fixture_deferred_func", tracer=self._tracer)
+            @tag_args
+            def fixture_deferred_func() -> "defer.Deferred[str]":
+                d1: defer.Deferred[str] = defer.Deferred()
+                d1.callback("foo")
+                return d1
+
+            result_d1 = fixture_deferred_func()
+
+            # let the tasks complete
+            reactor.pump((2,) * 8)
+
+            self.assertEqual(self.successResultOf(result_d1), "foo")
+
+        # the span should have been reported
+        self.assertEqual(
+            [span.operation_name for span in self._reporter.get_spans()],
+            ["fixture_deferred_func"],
+        )
+
+    def test_trace_decorator_async(self) -> None:
+        """
+        Test whether we can use `@trace_with_opname` (`@trace`) and `@tag_args`
+        with async functions
+        """
+        reactor = MemoryReactorClock()
+
+        with LoggingContext("root context"):
+
+            @trace_with_opname("fixture_async_func", tracer=self._tracer)
+            @tag_args
+            async def fixture_async_func() -> str:
+                return "foo"
+
+            d1 = defer.ensureDeferred(fixture_async_func())
+
+            # let the tasks complete
+            reactor.pump((2,) * 8)
+
+            self.assertEqual(self.successResultOf(d1), "foo")
+
+        # the span should have been reported
+        self.assertEqual(
+            [span.operation_name for span in self._reporter.get_spans()],
+            ["fixture_async_func"],
+        )
diff --git a/tests/module_api/test_api.py b/tests/module_api/test_api.py
index 169e29b590..02cef6f876 100644
--- a/tests/module_api/test_api.py
+++ b/tests/module_api/test_api.py
@@ -16,6 +16,7 @@ from unittest.mock import Mock
 from twisted.internet import defer
 
 from synapse.api.constants import EduTypes, EventTypes
+from synapse.api.errors import NotFoundError
 from synapse.events import EventBase
 from synapse.federation.units import Transaction
 from synapse.handlers.presence import UserPresenceState
@@ -29,7 +30,6 @@ from tests.replication._base import BaseMultiWorkerStreamTestCase
 from tests.test_utils import simple_async_mock
 from tests.test_utils.event_injection import inject_member_event
 from tests.unittest import HomeserverTestCase, override_config
-from tests.utils import USE_POSTGRES_FOR_TESTS
 
 
 class ModuleApiTestCase(HomeserverTestCase):
@@ -532,6 +532,34 @@ class ModuleApiTestCase(HomeserverTestCase):
         self.assertEqual(res["displayname"], "simone")
         self.assertIsNone(res["avatar_url"])
 
+    def test_update_room_membership_remote_join(self):
+        """Test that the module API can join a remote room."""
+        # Necessary to fake a remote join.
+        fake_stream_id = 1
+        mocked_remote_join = simple_async_mock(
+            return_value=("fake-event-id", fake_stream_id)
+        )
+        self.hs.get_room_member_handler()._remote_join = mocked_remote_join
+        fake_remote_host = f"{self.module_api.server_name}-remote"
+
+        # Given that the join is to be faked, we expect the relevant join event not to
+        # be persisted and the module API method to raise that.
+        self.get_failure(
+            defer.ensureDeferred(
+                self.module_api.update_room_membership(
+                    sender=f"@user:{self.module_api.server_name}",
+                    target=f"@user:{self.module_api.server_name}",
+                    room_id=f"!nonexistent:{fake_remote_host}",
+                    new_membership="join",
+                    remote_room_hosts=[fake_remote_host],
+                )
+            ),
+            NotFoundError,
+        )
+
+        # Check that a remote join was attempted.
+        self.assertEqual(mocked_remote_join.call_count, 1)
+
     def test_get_room_state(self):
         """Tests that a module can retrieve the state of a room through the module API."""
         user_id = self.register_user("peter", "hackme")
@@ -635,15 +663,80 @@ class ModuleApiTestCase(HomeserverTestCase):
             [{"set_tweak": "sound", "value": "default"}]
         )
 
+    def test_lookup_room_alias(self) -> None:
+        """Test that modules can resolve a room alias to a room ID."""
+        password = "password"
+        user_id = self.register_user("user", password)
+        access_token = self.login(user_id, password)
+        room_alias = "my-alias"
+        reference_room_id = self.helper.create_room_as(
+            tok=access_token, extra_content={"room_alias_name": room_alias}
+        )
+        self.assertIsNotNone(reference_room_id)
+
+        (room_id, _) = self.get_success(
+            self.module_api.lookup_room_alias(
+                f"#{room_alias}:{self.module_api.server_name}"
+            )
+        )
+
+        self.assertEqual(room_id, reference_room_id)
+
+    def test_create_room(self) -> None:
+        """Test that modules can create a room."""
+        # First test user validation (i.e. user is local).
+        self.get_failure(
+            self.module_api.create_room(
+                user_id=f"@user:{self.module_api.server_name}abc",
+                config={},
+                ratelimit=False,
+            ),
+            RuntimeError,
+        )
+
+        # Now do the happy path.
+        user_id = self.register_user("user", "password")
+        access_token = self.login(user_id, "password")
+
+        room_id, room_alias = self.get_success(
+            self.module_api.create_room(
+                user_id=user_id, config={"room_alias_name": "foo-bar"}, ratelimit=False
+            )
+        )
+
+        # Check room creator.
+        channel = self.make_request(
+            "GET",
+            f"/_matrix/client/v3/rooms/{room_id}/state/m.room.create",
+            access_token=access_token,
+        )
+        self.assertEqual(channel.code, 200, channel.result)
+        self.assertEqual(channel.json_body["creator"], user_id)
+
+        # Check room alias.
+        self.assertEquals(room_alias, f"#foo-bar:{self.module_api.server_name}")
+
+        # Let's try a room with no alias.
+        room_id, room_alias = self.get_success(
+            self.module_api.create_room(user_id=user_id, config={}, ratelimit=False)
+        )
+
+        # Check room creator.
+        channel = self.make_request(
+            "GET",
+            f"/_matrix/client/v3/rooms/{room_id}/state/m.room.create",
+            access_token=access_token,
+        )
+        self.assertEqual(channel.code, 200, channel.result)
+        self.assertEqual(channel.json_body["creator"], user_id)
+
+        # Check room alias.
+        self.assertIsNone(room_alias)
+
 
 class ModuleApiWorkerTestCase(BaseMultiWorkerStreamTestCase):
     """For testing ModuleApi functionality in a multi-worker setup"""
 
-    # Testing stream ID replication from the main to worker processes requires postgres
-    # (due to needing `MultiWriterIdGenerator`).
-    if not USE_POSTGRES_FOR_TESTS:
-        skip = "Requires Postgres"
-
     servlets = [
         admin.register_servlets,
         login.register_servlets,
@@ -653,7 +746,6 @@ class ModuleApiWorkerTestCase(BaseMultiWorkerStreamTestCase):
 
     def default_config(self):
         conf = super().default_config()
-        conf["redis"] = {"enabled": "true"}
         conf["stream_writers"] = {"presence": ["presence_writer"]}
         conf["instance_map"] = {
             "presence_writer": {"host": "testserv", "port": 1001},
diff --git a/tests/replication/_base.py b/tests/replication/_base.py
index 970d5e533b..ce53f808db 100644
--- a/tests/replication/_base.py
+++ b/tests/replication/_base.py
@@ -24,11 +24,11 @@ from synapse.http.site import SynapseRequest, SynapseSite
 from synapse.replication.http import ReplicationRestResource
 from synapse.replication.tcp.client import ReplicationDataHandler
 from synapse.replication.tcp.handler import ReplicationCommandHandler
-from synapse.replication.tcp.protocol import ClientReplicationStreamProtocol
-from synapse.replication.tcp.resource import (
-    ReplicationStreamProtocolFactory,
+from synapse.replication.tcp.protocol import (
+    ClientReplicationStreamProtocol,
     ServerReplicationStreamProtocol,
 )
+from synapse.replication.tcp.resource import ReplicationStreamProtocolFactory
 from synapse.server import HomeServer
 
 from tests import unittest
@@ -220,15 +220,34 @@ class BaseStreamTestCase(unittest.HomeserverTestCase):
 class BaseMultiWorkerStreamTestCase(unittest.HomeserverTestCase):
     """Base class for tests running multiple workers.
 
+    Enables Redis, providing a fake Redis server.
+
     Automatically handle HTTP replication requests from workers to master,
     unlike `BaseStreamTestCase`.
     """
 
+    if not hiredis:
+        skip = "Requires hiredis"
+
+    if not USE_POSTGRES_FOR_TESTS:
+        # Redis replication only takes place on Postgres
+        skip = "Requires Postgres"
+
+    def default_config(self) -> Dict[str, Any]:
+        """
+        Overrides the default config to enable Redis.
+        Even if the test only uses make_worker_hs, the main process needs Redis
+        enabled otherwise it won't create a Fake Redis server to listen on the
+        Redis port and accept fake TCP connections.
+        """
+        base = super().default_config()
+        base["redis"] = {"enabled": True}
+        return base
+
     def setUp(self):
         super().setUp()
 
         # build a replication server
-        self.server_factory = ReplicationStreamProtocolFactory(self.hs)
         self.streamer = self.hs.get_replication_streamer()
 
         # Fake in memory Redis server that servers can connect to.
@@ -247,15 +266,14 @@ class BaseMultiWorkerStreamTestCase(unittest.HomeserverTestCase):
         # handling inbound HTTP requests to that instance.
         self._hs_to_site = {self.hs: self.site}
 
-        if self.hs.config.redis.redis_enabled:
-            # Handle attempts to connect to fake redis server.
-            self.reactor.add_tcp_client_callback(
-                "localhost",
-                6379,
-                self.connect_any_redis_attempts,
-            )
+        # Handle attempts to connect to fake redis server.
+        self.reactor.add_tcp_client_callback(
+            "localhost",
+            6379,
+            self.connect_any_redis_attempts,
+        )
 
-            self.hs.get_replication_command_handler().start_replication(self.hs)
+        self.hs.get_replication_command_handler().start_replication(self.hs)
 
         # When we see a connection attempt to the master replication listener we
         # automatically set up the connection. This is so that tests don't
@@ -339,27 +357,6 @@ class BaseMultiWorkerStreamTestCase(unittest.HomeserverTestCase):
         store = worker_hs.get_datastores().main
         store.db_pool._db_pool = self.database_pool._db_pool
 
-        # Set up TCP replication between master and the new worker if we don't
-        # have Redis support enabled.
-        if not worker_hs.config.redis.redis_enabled:
-            repl_handler = ReplicationCommandHandler(worker_hs)
-            client = ClientReplicationStreamProtocol(
-                worker_hs,
-                "client",
-                "test",
-                self.clock,
-                repl_handler,
-            )
-            server = self.server_factory.buildProtocol(
-                IPv4Address("TCP", "127.0.0.1", 0)
-            )
-
-            client_transport = FakeTransport(server, self.reactor)
-            client.makeConnection(client_transport)
-
-            server_transport = FakeTransport(client, self.reactor)
-            server.makeConnection(server_transport)
-
         # Set up a resource for the worker
         resource = ReplicationRestResource(worker_hs)
 
@@ -378,8 +375,7 @@ class BaseMultiWorkerStreamTestCase(unittest.HomeserverTestCase):
             reactor=self.reactor,
         )
 
-        if worker_hs.config.redis.redis_enabled:
-            worker_hs.get_replication_command_handler().start_replication(worker_hs)
+        worker_hs.get_replication_command_handler().start_replication(worker_hs)
 
         return worker_hs
 
@@ -582,27 +578,3 @@ class FakeRedisPubSubProtocol(Protocol):
 
     def connectionLost(self, reason):
         self._server.remove_subscriber(self)
-
-
-class RedisMultiWorkerStreamTestCase(BaseMultiWorkerStreamTestCase):
-    """
-    A test case that enables Redis, providing a fake Redis server.
-    """
-
-    if not hiredis:
-        skip = "Requires hiredis"
-
-    if not USE_POSTGRES_FOR_TESTS:
-        # Redis replication only takes place on Postgres
-        skip = "Requires Postgres"
-
-    def default_config(self) -> Dict[str, Any]:
-        """
-        Overrides the default config to enable Redis.
-        Even if the test only uses make_worker_hs, the main process needs Redis
-        enabled otherwise it won't create a Fake Redis server to listen on the
-        Redis port and accept fake TCP connections.
-        """
-        base = super().default_config()
-        base["redis"] = {"enabled": True}
-        return base
diff --git a/tests/replication/slave/storage/test_account_data.py b/tests/replication/slave/storage/test_account_data.py
deleted file mode 100644
index 1524087c43..0000000000
--- a/tests/replication/slave/storage/test_account_data.py
+++ /dev/null
@@ -1,42 +0,0 @@
-# Copyright 2016 OpenMarket Ltd
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-from synapse.replication.slave.storage.account_data import SlavedAccountDataStore
-
-from ._base import BaseSlavedStoreTestCase
-
-USER_ID = "@feeling:blue"
-TYPE = "my.type"
-
-
-class SlavedAccountDataStoreTestCase(BaseSlavedStoreTestCase):
-
-    STORE_TYPE = SlavedAccountDataStore
-
-    def test_user_account_data(self):
-        self.get_success(
-            self.master_store.add_account_data_for_user(USER_ID, TYPE, {"a": 1})
-        )
-        self.replicate()
-        self.check(
-            "get_global_account_data_by_type_for_user", [USER_ID, TYPE], {"a": 1}
-        )
-
-        self.get_success(
-            self.master_store.add_account_data_for_user(USER_ID, TYPE, {"a": 2})
-        )
-        self.replicate()
-        self.check(
-            "get_global_account_data_by_type_for_user", [USER_ID, TYPE], {"a": 2}
-        )
diff --git a/tests/replication/tcp/test_handler.py b/tests/replication/tcp/test_handler.py
index e6a19eafd5..1e299d2d67 100644
--- a/tests/replication/tcp/test_handler.py
+++ b/tests/replication/tcp/test_handler.py
@@ -12,10 +12,10 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from tests.replication._base import RedisMultiWorkerStreamTestCase
+from tests.replication._base import BaseMultiWorkerStreamTestCase
 
 
-class ChannelsTestCase(RedisMultiWorkerStreamTestCase):
+class ChannelsTestCase(BaseMultiWorkerStreamTestCase):
     def test_subscribed_to_enough_redis_channels(self) -> None:
         # The default main process is subscribed to the USER_IP channel.
         self.assertCountEqual(
diff --git a/tests/replication/test_sharded_event_persister.py b/tests/replication/test_sharded_event_persister.py
index a7ca68069e..541d390286 100644
--- a/tests/replication/test_sharded_event_persister.py
+++ b/tests/replication/test_sharded_event_persister.py
@@ -20,7 +20,6 @@ from synapse.storage.util.id_generators import MultiWriterIdGenerator
 
 from tests.replication._base import BaseMultiWorkerStreamTestCase
 from tests.server import make_request
-from tests.utils import USE_POSTGRES_FOR_TESTS
 
 logger = logging.getLogger(__name__)
 
@@ -28,11 +27,6 @@ logger = logging.getLogger(__name__)
 class EventPersisterShardTestCase(BaseMultiWorkerStreamTestCase):
     """Checks event persisting sharding works"""
 
-    # Event persister sharding requires postgres (due to needing
-    # `MultiWriterIdGenerator`).
-    if not USE_POSTGRES_FOR_TESTS:
-        skip = "Requires Postgres"
-
     servlets = [
         admin.register_servlets_for_client_rest_resource,
         room.register_servlets,
@@ -50,7 +44,6 @@ class EventPersisterShardTestCase(BaseMultiWorkerStreamTestCase):
 
     def default_config(self):
         conf = super().default_config()
-        conf["redis"] = {"enabled": "true"}
         conf["stream_writers"] = {"events": ["worker1", "worker2"]}
         conf["instance_map"] = {
             "worker1": {"host": "testserv", "port": 1001},
diff --git a/tests/rest/admin/test_admin.py b/tests/rest/admin/test_admin.py
index 82ac5991e6..a8f6436836 100644
--- a/tests/rest/admin/test_admin.py
+++ b/tests/rest/admin/test_admin.py
@@ -13,7 +13,6 @@
 # limitations under the License.
 
 import urllib.parse
-from http import HTTPStatus
 
 from parameterized import parameterized
 
@@ -42,7 +41,7 @@ class VersionTestCase(unittest.HomeserverTestCase):
     def test_version_string(self) -> None:
         channel = self.make_request("GET", self.url, shorthand=False)
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(
             {"server_version", "python_version"}, set(channel.json_body.keys())
         )
@@ -79,10 +78,10 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
 
         # Should be quarantined
         self.assertEqual(
-            HTTPStatus.NOT_FOUND,
+            404,
             channel.code,
             msg=(
-                "Expected to receive a HTTPStatus.NOT_FOUND on accessing quarantined media: %s"
+                "Expected to receive a 404 on accessing quarantined media: %s"
                 % server_and_media_id
             ),
         )
@@ -107,7 +106,7 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
 
         # Expect a forbidden error
         self.assertEqual(
-            HTTPStatus.FORBIDDEN,
+            403,
             channel.code,
             msg="Expected forbidden on quarantining media as a non-admin",
         )
@@ -139,7 +138,7 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
         )
 
         # Should be successful
-        self.assertEqual(HTTPStatus.OK, channel.code)
+        self.assertEqual(200, channel.code)
 
         # Quarantine the media
         url = "/_synapse/admin/v1/media/quarantine/%s/%s" % (
@@ -152,7 +151,7 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
             access_token=admin_user_tok,
         )
         self.pump(1.0)
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Attempt to access the media
         self._ensure_quarantined(admin_user_tok, server_name_and_media_id)
@@ -209,7 +208,7 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
             access_token=admin_user_tok,
         )
         self.pump(1.0)
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(
             channel.json_body, {"num_quarantined": 2}, "Expected 2 quarantined items"
         )
@@ -251,7 +250,7 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
             access_token=admin_user_tok,
         )
         self.pump(1.0)
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(
             channel.json_body, {"num_quarantined": 2}, "Expected 2 quarantined items"
         )
@@ -285,7 +284,7 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
         url = "/_synapse/admin/v1/media/protect/%s" % (urllib.parse.quote(media_id_2),)
         channel = self.make_request("POST", url, access_token=admin_user_tok)
         self.pump(1.0)
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Quarantine all media by this user
         url = "/_synapse/admin/v1/user/%s/media/quarantine" % urllib.parse.quote(
@@ -297,7 +296,7 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
             access_token=admin_user_tok,
         )
         self.pump(1.0)
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(
             channel.json_body, {"num_quarantined": 1}, "Expected 1 quarantined item"
         )
@@ -318,10 +317,10 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
 
         # Shouldn't be quarantined
         self.assertEqual(
-            HTTPStatus.OK,
+            200,
             channel.code,
             msg=(
-                "Expected to receive a HTTPStatus.OK on accessing not-quarantined media: %s"
+                "Expected to receive a 200 on accessing not-quarantined media: %s"
                 % server_and_media_id_2
             ),
         )
@@ -350,7 +349,7 @@ class PurgeHistoryTestCase(unittest.HomeserverTestCase):
     def test_purge_history(self) -> None:
         """
         Simple test of purge history API.
-        Test only that is is possible to call, get status HTTPStatus.OK and purge_id.
+        Test only that is is possible to call, get status 200 and purge_id.
         """
 
         channel = self.make_request(
@@ -360,7 +359,7 @@ class PurgeHistoryTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertIn("purge_id", channel.json_body)
         purge_id = channel.json_body["purge_id"]
 
@@ -371,5 +370,5 @@ class PurgeHistoryTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("complete", channel.json_body["status"])
diff --git a/tests/rest/admin/test_background_updates.py b/tests/rest/admin/test_background_updates.py
index 6cf56b1e35..d507a3af8d 100644
--- a/tests/rest/admin/test_background_updates.py
+++ b/tests/rest/admin/test_background_updates.py
@@ -11,7 +11,6 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from http import HTTPStatus
 from typing import Collection
 
 from parameterized import parameterized
@@ -51,7 +50,7 @@ class BackgroundUpdatesTestCase(unittest.HomeserverTestCase):
     )
     def test_requester_is_no_admin(self, method: str, url: str) -> None:
         """
-        If the user is not a server admin, an error HTTPStatus.FORBIDDEN is returned.
+        If the user is not a server admin, an error 403 is returned.
         """
 
         self.register_user("user", "pass", admin=False)
@@ -64,7 +63,7 @@ class BackgroundUpdatesTestCase(unittest.HomeserverTestCase):
             access_token=other_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_invalid_parameter(self) -> None:
@@ -81,7 +80,7 @@ class BackgroundUpdatesTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_PARAM, channel.json_body["errcode"])
 
         # job_name invalid
@@ -92,7 +91,7 @@ class BackgroundUpdatesTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.UNKNOWN, channel.json_body["errcode"])
 
     def _register_bg_update(self) -> None:
@@ -125,7 +124,7 @@ class BackgroundUpdatesTestCase(unittest.HomeserverTestCase):
             "/_synapse/admin/v1/background_updates/status",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Background updates should be enabled, but none should be running.
         self.assertDictEqual(
@@ -147,7 +146,7 @@ class BackgroundUpdatesTestCase(unittest.HomeserverTestCase):
             "/_synapse/admin/v1/background_updates/status",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Background updates should be enabled, and one should be running.
         self.assertDictEqual(
@@ -181,7 +180,7 @@ class BackgroundUpdatesTestCase(unittest.HomeserverTestCase):
             "/_synapse/admin/v1/background_updates/enabled",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertDictEqual(channel.json_body, {"enabled": True})
 
         # Disable the BG updates
@@ -191,7 +190,7 @@ class BackgroundUpdatesTestCase(unittest.HomeserverTestCase):
             content={"enabled": False},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertDictEqual(channel.json_body, {"enabled": False})
 
         # Advance a bit and get the current status, note this will finish the in
@@ -204,7 +203,7 @@ class BackgroundUpdatesTestCase(unittest.HomeserverTestCase):
             "/_synapse/admin/v1/background_updates/status",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertDictEqual(
             channel.json_body,
             {
@@ -231,7 +230,7 @@ class BackgroundUpdatesTestCase(unittest.HomeserverTestCase):
             "/_synapse/admin/v1/background_updates/status",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # There should be no change from the previous /status response.
         self.assertDictEqual(
@@ -259,7 +258,7 @@ class BackgroundUpdatesTestCase(unittest.HomeserverTestCase):
             content={"enabled": True},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         self.assertDictEqual(channel.json_body, {"enabled": True})
 
@@ -270,7 +269,7 @@ class BackgroundUpdatesTestCase(unittest.HomeserverTestCase):
             "/_synapse/admin/v1/background_updates/status",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Background updates should be enabled and making progress.
         self.assertDictEqual(
@@ -325,7 +324,7 @@ class BackgroundUpdatesTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # test that each background update is waiting now
         for update in updates:
@@ -365,4 +364,4 @@ class BackgroundUpdatesTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
diff --git a/tests/rest/admin/test_device.py b/tests/rest/admin/test_device.py
index f7080bda87..d52aee8f92 100644
--- a/tests/rest/admin/test_device.py
+++ b/tests/rest/admin/test_device.py
@@ -12,7 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import urllib.parse
-from http import HTTPStatus
 
 from parameterized import parameterized
 
@@ -58,7 +57,7 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
         channel = self.make_request(method, self.url, b"{}")
 
         self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
+            401,
             channel.code,
             msg=channel.json_body,
         )
@@ -76,7 +75,7 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
         )
 
         self.assertEqual(
-            HTTPStatus.FORBIDDEN,
+            403,
             channel.code,
             msg=channel.json_body,
         )
@@ -85,7 +84,7 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
     @parameterized.expand(["GET", "PUT", "DELETE"])
     def test_user_does_not_exist(self, method: str) -> None:
         """
-        Tests that a lookup for a user that does not exist returns a HTTPStatus.NOT_FOUND
+        Tests that a lookup for a user that does not exist returns a 404
         """
         url = (
             "/_synapse/admin/v2/users/@unknown_person:test/devices/%s"
@@ -98,13 +97,13 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     @parameterized.expand(["GET", "PUT", "DELETE"])
     def test_user_is_not_local(self, method: str) -> None:
         """
-        Tests that a lookup for a user that is not a local returns a HTTPStatus.BAD_REQUEST
+        Tests that a lookup for a user that is not a local returns a 400
         """
         url = (
             "/_synapse/admin/v2/users/@unknown_person:unknown_domain/devices/%s"
@@ -117,12 +116,12 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Can only lookup local users", channel.json_body["error"])
 
     def test_unknown_device(self) -> None:
         """
-        Tests that a lookup for a device that does not exist returns either HTTPStatus.NOT_FOUND or HTTPStatus.OK.
+        Tests that a lookup for a device that does not exist returns either 404 or 200.
         """
         url = "/_synapse/admin/v2/users/%s/devices/unknown_device" % urllib.parse.quote(
             self.other_user
@@ -134,7 +133,7 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
         channel = self.make_request(
@@ -143,7 +142,7 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         channel = self.make_request(
             "DELETE",
@@ -151,8 +150,8 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        # Delete unknown device returns status HTTPStatus.OK
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        # Delete unknown device returns status 200
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
     def test_update_device_too_long_display_name(self) -> None:
         """
@@ -179,7 +178,7 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
             content=update,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.TOO_LARGE, channel.json_body["errcode"])
 
         # Ensure the display name was not updated.
@@ -189,12 +188,12 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("new display", channel.json_body["display_name"])
 
     def test_update_no_display_name(self) -> None:
         """
-        Tests that a update for a device without JSON returns a HTTPStatus.OK
+        Tests that a update for a device without JSON returns a 200
         """
         # Set iniital display name.
         update = {"display_name": "new display"}
@@ -210,7 +209,7 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Ensure the display name was not updated.
         channel = self.make_request(
@@ -219,7 +218,7 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("new display", channel.json_body["display_name"])
 
     def test_update_display_name(self) -> None:
@@ -234,7 +233,7 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
             content={"display_name": "new displayname"},
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Check new display_name
         channel = self.make_request(
@@ -243,7 +242,7 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("new displayname", channel.json_body["display_name"])
 
     def test_get_device(self) -> None:
@@ -256,7 +255,7 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(self.other_user, channel.json_body["user_id"])
         # Check that all fields are available
         self.assertIn("user_id", channel.json_body)
@@ -281,7 +280,7 @@ class DeviceRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Ensure that the number of devices is decreased
         res = self.get_success(self.handler.get_devices_by_user(self.other_user))
@@ -312,7 +311,7 @@ class DevicesRestTestCase(unittest.HomeserverTestCase):
         channel = self.make_request("GET", self.url, b"{}")
 
         self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
+            401,
             channel.code,
             msg=channel.json_body,
         )
@@ -331,7 +330,7 @@ class DevicesRestTestCase(unittest.HomeserverTestCase):
         )
 
         self.assertEqual(
-            HTTPStatus.FORBIDDEN,
+            403,
             channel.code,
             msg=channel.json_body,
         )
@@ -339,7 +338,7 @@ class DevicesRestTestCase(unittest.HomeserverTestCase):
 
     def test_user_does_not_exist(self) -> None:
         """
-        Tests that a lookup for a user that does not exist returns a HTTPStatus.NOT_FOUND
+        Tests that a lookup for a user that does not exist returns a 404
         """
         url = "/_synapse/admin/v2/users/@unknown_person:test/devices"
         channel = self.make_request(
@@ -348,12 +347,12 @@ class DevicesRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     def test_user_is_not_local(self) -> None:
         """
-        Tests that a lookup for a user that is not a local returns a HTTPStatus.BAD_REQUEST
+        Tests that a lookup for a user that is not a local returns a 400
         """
         url = "/_synapse/admin/v2/users/@unknown_person:unknown_domain/devices"
 
@@ -363,7 +362,7 @@ class DevicesRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Can only lookup local users", channel.json_body["error"])
 
     def test_user_has_no_devices(self) -> None:
@@ -379,7 +378,7 @@ class DevicesRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(0, channel.json_body["total"])
         self.assertEqual(0, len(channel.json_body["devices"]))
 
@@ -399,7 +398,7 @@ class DevicesRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(number_devices, channel.json_body["total"])
         self.assertEqual(number_devices, len(channel.json_body["devices"]))
         self.assertEqual(self.other_user, channel.json_body["devices"][0]["user_id"])
@@ -438,7 +437,7 @@ class DeleteDevicesRestTestCase(unittest.HomeserverTestCase):
         channel = self.make_request("POST", self.url, b"{}")
 
         self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
+            401,
             channel.code,
             msg=channel.json_body,
         )
@@ -457,7 +456,7 @@ class DeleteDevicesRestTestCase(unittest.HomeserverTestCase):
         )
 
         self.assertEqual(
-            HTTPStatus.FORBIDDEN,
+            403,
             channel.code,
             msg=channel.json_body,
         )
@@ -465,7 +464,7 @@ class DeleteDevicesRestTestCase(unittest.HomeserverTestCase):
 
     def test_user_does_not_exist(self) -> None:
         """
-        Tests that a lookup for a user that does not exist returns a HTTPStatus.NOT_FOUND
+        Tests that a lookup for a user that does not exist returns a 404
         """
         url = "/_synapse/admin/v2/users/@unknown_person:test/delete_devices"
         channel = self.make_request(
@@ -474,12 +473,12 @@ class DeleteDevicesRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     def test_user_is_not_local(self) -> None:
         """
-        Tests that a lookup for a user that is not a local returns a HTTPStatus.BAD_REQUEST
+        Tests that a lookup for a user that is not a local returns a 400
         """
         url = "/_synapse/admin/v2/users/@unknown_person:unknown_domain/delete_devices"
 
@@ -489,12 +488,12 @@ class DeleteDevicesRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Can only lookup local users", channel.json_body["error"])
 
     def test_unknown_devices(self) -> None:
         """
-        Tests that a remove of a device that does not exist returns HTTPStatus.OK.
+        Tests that a remove of a device that does not exist returns 200.
         """
         channel = self.make_request(
             "POST",
@@ -503,8 +502,8 @@ class DeleteDevicesRestTestCase(unittest.HomeserverTestCase):
             content={"devices": ["unknown_device1", "unknown_device2"]},
         )
 
-        # Delete unknown devices returns status HTTPStatus.OK
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        # Delete unknown devices returns status 200
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
     def test_delete_devices(self) -> None:
         """
@@ -533,7 +532,7 @@ class DeleteDevicesRestTestCase(unittest.HomeserverTestCase):
             content={"devices": device_ids},
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         res = self.get_success(self.handler.get_devices_by_user(self.other_user))
         self.assertEqual(0, len(res))
diff --git a/tests/rest/admin/test_event_reports.py b/tests/rest/admin/test_event_reports.py
index 4f89f8b534..8a4e5c3f77 100644
--- a/tests/rest/admin/test_event_reports.py
+++ b/tests/rest/admin/test_event_reports.py
@@ -11,7 +11,6 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from http import HTTPStatus
 from typing import List
 
 from twisted.test.proto_helpers import MemoryReactor
@@ -81,16 +80,12 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
         """
         channel = self.make_request("GET", self.url, b"{}")
 
-        self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_requester_is_no_admin(self) -> None:
         """
-        If the user is not a server admin, an error HTTPStatus.FORBIDDEN is returned.
+        If the user is not a server admin, an error 403 is returned.
         """
 
         channel = self.make_request(
@@ -99,11 +94,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.other_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.FORBIDDEN,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_default_success(self) -> None:
@@ -117,7 +108,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 20)
         self.assertEqual(len(channel.json_body["event_reports"]), 20)
         self.assertNotIn("next_token", channel.json_body)
@@ -134,7 +125,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 20)
         self.assertEqual(len(channel.json_body["event_reports"]), 5)
         self.assertEqual(channel.json_body["next_token"], 5)
@@ -151,7 +142,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 20)
         self.assertEqual(len(channel.json_body["event_reports"]), 15)
         self.assertNotIn("next_token", channel.json_body)
@@ -168,7 +159,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 20)
         self.assertEqual(channel.json_body["next_token"], 15)
         self.assertEqual(len(channel.json_body["event_reports"]), 10)
@@ -185,7 +176,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 10)
         self.assertEqual(len(channel.json_body["event_reports"]), 10)
         self.assertNotIn("next_token", channel.json_body)
@@ -205,7 +196,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 10)
         self.assertEqual(len(channel.json_body["event_reports"]), 10)
         self.assertNotIn("next_token", channel.json_body)
@@ -225,7 +216,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 5)
         self.assertEqual(len(channel.json_body["event_reports"]), 5)
         self.assertNotIn("next_token", channel.json_body)
@@ -247,7 +238,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 20)
         self.assertEqual(len(channel.json_body["event_reports"]), 20)
         report = 1
@@ -265,7 +256,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 20)
         self.assertEqual(len(channel.json_body["event_reports"]), 20)
         report = 1
@@ -278,7 +269,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
 
     def test_invalid_search_order(self) -> None:
         """
-        Testing that a invalid search order returns a HTTPStatus.BAD_REQUEST
+        Testing that a invalid search order returns a 400
         """
 
         channel = self.make_request(
@@ -287,17 +278,13 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
         self.assertEqual("Unknown direction: bar", channel.json_body["error"])
 
     def test_limit_is_negative(self) -> None:
         """
-        Testing that a negative limit parameter returns a HTTPStatus.BAD_REQUEST
+        Testing that a negative limit parameter returns a 400
         """
 
         channel = self.make_request(
@@ -306,16 +293,12 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
     def test_from_is_negative(self) -> None:
         """
-        Testing that a negative from parameter returns a HTTPStatus.BAD_REQUEST
+        Testing that a negative from parameter returns a 400
         """
 
         channel = self.make_request(
@@ -324,11 +307,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
     def test_next_token(self) -> None:
@@ -344,7 +323,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 20)
         self.assertEqual(len(channel.json_body["event_reports"]), 20)
         self.assertNotIn("next_token", channel.json_body)
@@ -357,7 +336,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 20)
         self.assertEqual(len(channel.json_body["event_reports"]), 20)
         self.assertNotIn("next_token", channel.json_body)
@@ -370,7 +349,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 20)
         self.assertEqual(len(channel.json_body["event_reports"]), 19)
         self.assertEqual(channel.json_body["next_token"], 19)
@@ -384,7 +363,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 20)
         self.assertEqual(len(channel.json_body["event_reports"]), 1)
         self.assertNotIn("next_token", channel.json_body)
@@ -400,7 +379,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             {"score": -100, "reason": "this makes me sad"},
             access_token=user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
     def _create_event_and_report_without_parameters(
         self, room_id: str, user_tok: str
@@ -415,7 +394,7 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             {},
             access_token=user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
     def _check_fields(self, content: List[JsonDict]) -> None:
         """Checks that all attributes are present in an event report"""
@@ -431,6 +410,33 @@ class EventReportsTestCase(unittest.HomeserverTestCase):
             self.assertIn("score", c)
             self.assertIn("reason", c)
 
+    def test_count_correct_despite_table_deletions(self) -> None:
+        """
+        Tests that the count matches the number of rows, even if rows in joined tables
+        are missing.
+        """
+
+        # Delete rows from room_stats_state for one of our rooms.
+        self.get_success(
+            self.hs.get_datastores().main.db_pool.simple_delete(
+                "room_stats_state", {"room_id": self.room_id1}, desc="_"
+            )
+        )
+
+        channel = self.make_request(
+            "GET",
+            self.url,
+            access_token=self.admin_user_tok,
+        )
+
+        self.assertEqual(200, channel.code, msg=channel.json_body)
+        # The 'total' field is 10 because only 10 reports will actually
+        # be retrievable since we deleted the rows in the room_stats_state
+        # table.
+        self.assertEqual(channel.json_body["total"], 10)
+        # This is consistent with the number of rows actually returned.
+        self.assertEqual(len(channel.json_body["event_reports"]), 10)
+
 
 class EventReportDetailTestCase(unittest.HomeserverTestCase):
     servlets = [
@@ -466,16 +472,12 @@ class EventReportDetailTestCase(unittest.HomeserverTestCase):
         """
         channel = self.make_request("GET", self.url, b"{}")
 
-        self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_requester_is_no_admin(self) -> None:
         """
-        If the user is not a server admin, an error HTTPStatus.FORBIDDEN is returned.
+        If the user is not a server admin, an error 403 is returned.
         """
 
         channel = self.make_request(
@@ -484,11 +486,7 @@ class EventReportDetailTestCase(unittest.HomeserverTestCase):
             access_token=self.other_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.FORBIDDEN,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_default_success(self) -> None:
@@ -502,12 +500,12 @@ class EventReportDetailTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self._check_fields(channel.json_body)
 
     def test_invalid_report_id(self) -> None:
         """
-        Testing that an invalid `report_id` returns a HTTPStatus.BAD_REQUEST.
+        Testing that an invalid `report_id` returns a 400.
         """
 
         # `report_id` is negative
@@ -517,11 +515,7 @@ class EventReportDetailTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
         self.assertEqual(
             "The report_id parameter must be a string representing a positive integer.",
@@ -535,11 +529,7 @@ class EventReportDetailTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
         self.assertEqual(
             "The report_id parameter must be a string representing a positive integer.",
@@ -553,11 +543,7 @@ class EventReportDetailTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
         self.assertEqual(
             "The report_id parameter must be a string representing a positive integer.",
@@ -566,7 +552,7 @@ class EventReportDetailTestCase(unittest.HomeserverTestCase):
 
     def test_report_id_not_found(self) -> None:
         """
-        Testing that a not existing `report_id` returns a HTTPStatus.NOT_FOUND.
+        Testing that a not existing `report_id` returns a 404.
         """
 
         channel = self.make_request(
@@ -575,11 +561,7 @@ class EventReportDetailTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.NOT_FOUND,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
         self.assertEqual("Event report not found", channel.json_body["error"])
 
@@ -594,7 +576,7 @@ class EventReportDetailTestCase(unittest.HomeserverTestCase):
             {"score": -100, "reason": "this makes me sad"},
             access_token=user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
     def _check_fields(self, content: JsonDict) -> None:
         """Checks that all attributes are present in a event report"""
diff --git a/tests/rest/admin/test_federation.py b/tests/rest/admin/test_federation.py
index 929bbdc37d..4c7864c629 100644
--- a/tests/rest/admin/test_federation.py
+++ b/tests/rest/admin/test_federation.py
@@ -11,7 +11,6 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from http import HTTPStatus
 from typing import List, Optional
 
 from parameterized import parameterized
@@ -64,7 +63,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=other_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_invalid_parameter(self) -> None:
@@ -77,7 +76,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # negative from
@@ -87,7 +86,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # unkown order_by
@@ -97,7 +96,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # invalid search order
@@ -107,7 +106,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # invalid destination
@@ -117,7 +116,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
         # invalid destination
@@ -127,7 +126,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     def test_limit(self) -> None:
@@ -142,7 +141,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_destinations)
         self.assertEqual(len(channel.json_body["destinations"]), 5)
         self.assertEqual(channel.json_body["next_token"], "5")
@@ -160,7 +159,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_destinations)
         self.assertEqual(len(channel.json_body["destinations"]), 15)
         self.assertNotIn("next_token", channel.json_body)
@@ -178,7 +177,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_destinations)
         self.assertEqual(channel.json_body["next_token"], "15")
         self.assertEqual(len(channel.json_body["destinations"]), 10)
@@ -198,7 +197,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_destinations)
         self.assertEqual(len(channel.json_body["destinations"]), number_destinations)
         self.assertNotIn("next_token", channel.json_body)
@@ -211,7 +210,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_destinations)
         self.assertEqual(len(channel.json_body["destinations"]), number_destinations)
         self.assertNotIn("next_token", channel.json_body)
@@ -224,7 +223,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_destinations)
         self.assertEqual(len(channel.json_body["destinations"]), 19)
         self.assertEqual(channel.json_body["next_token"], "19")
@@ -238,7 +237,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_destinations)
         self.assertEqual(len(channel.json_body["destinations"]), 1)
         self.assertNotIn("next_token", channel.json_body)
@@ -255,7 +254,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(number_destinations, len(channel.json_body["destinations"]))
         self.assertEqual(number_destinations, channel.json_body["total"])
 
@@ -290,7 +289,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
                 url,
                 access_token=self.admin_user_tok,
             )
-            self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+            self.assertEqual(200, channel.code, msg=channel.json_body)
             self.assertEqual(channel.json_body["total"], len(expected_destination_list))
 
             returned_order = [
@@ -376,7 +375,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
                 url.encode("ascii"),
                 access_token=self.admin_user_tok,
             )
-            self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+            self.assertEqual(200, channel.code, msg=channel.json_body)
 
             # Check that destinations were returned
             self.assertTrue("destinations" in channel.json_body)
@@ -418,7 +417,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("sub0.example.com", channel.json_body["destination"])
 
         # Check that all fields are available
@@ -435,7 +434,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("sub0.example.com", channel.json_body["destination"])
         self.assertEqual(0, channel.json_body["retry_last_ts"])
         self.assertEqual(0, channel.json_body["retry_interval"])
@@ -452,7 +451,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         retry_timings = self.get_success(
             self.store.get_destination_retry_timings("sub0.example.com")
@@ -469,7 +468,7 @@ class FederationTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(
             "The retry timing does not need to be reset for this destination.",
             channel.json_body["error"],
@@ -561,7 +560,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=other_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_invalid_parameter(self) -> None:
@@ -574,7 +573,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # negative from
@@ -584,7 +583,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # invalid search order
@@ -594,7 +593,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # invalid destination
@@ -604,7 +603,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     def test_limit(self) -> None:
@@ -619,7 +618,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_rooms)
         self.assertEqual(len(channel.json_body["rooms"]), 3)
         self.assertEqual(channel.json_body["next_token"], "3")
@@ -637,7 +636,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_rooms)
         self.assertEqual(len(channel.json_body["rooms"]), 5)
         self.assertNotIn("next_token", channel.json_body)
@@ -655,7 +654,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_rooms)
         self.assertEqual(channel.json_body["next_token"], "8")
         self.assertEqual(len(channel.json_body["rooms"]), 5)
@@ -673,7 +672,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel_asc.code, msg=channel_asc.json_body)
+        self.assertEqual(200, channel_asc.code, msg=channel_asc.json_body)
         self.assertEqual(channel_asc.json_body["total"], number_rooms)
         self.assertEqual(number_rooms, len(channel_asc.json_body["rooms"]))
         self._check_fields(channel_asc.json_body["rooms"])
@@ -685,7 +684,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel_desc.code, msg=channel_desc.json_body)
+        self.assertEqual(200, channel_desc.code, msg=channel_desc.json_body)
         self.assertEqual(channel_desc.json_body["total"], number_rooms)
         self.assertEqual(number_rooms, len(channel_desc.json_body["rooms"]))
         self._check_fields(channel_desc.json_body["rooms"])
@@ -711,7 +710,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_rooms)
         self.assertEqual(len(channel.json_body["rooms"]), number_rooms)
         self.assertNotIn("next_token", channel.json_body)
@@ -724,7 +723,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_rooms)
         self.assertEqual(len(channel.json_body["rooms"]), number_rooms)
         self.assertNotIn("next_token", channel.json_body)
@@ -737,7 +736,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_rooms)
         self.assertEqual(len(channel.json_body["rooms"]), 4)
         self.assertEqual(channel.json_body["next_token"], "4")
@@ -751,7 +750,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_rooms)
         self.assertEqual(len(channel.json_body["rooms"]), 1)
         self.assertNotIn("next_token", channel.json_body)
@@ -767,7 +766,7 @@ class DestinationMembershipTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_rooms)
         self.assertEqual(number_rooms, len(channel.json_body["rooms"]))
         self._check_fields(channel.json_body["rooms"])
diff --git a/tests/rest/admin/test_media.py b/tests/rest/admin/test_media.py
index e909e444ac..aadb31ca83 100644
--- a/tests/rest/admin/test_media.py
+++ b/tests/rest/admin/test_media.py
@@ -13,7 +13,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import os
-from http import HTTPStatus
 
 from parameterized import parameterized
 
@@ -60,7 +59,7 @@ class DeleteMediaByIDTestCase(unittest.HomeserverTestCase):
         channel = self.make_request("DELETE", url, b"{}")
 
         self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
+            401,
             channel.code,
             msg=channel.json_body,
         )
@@ -81,16 +80,12 @@ class DeleteMediaByIDTestCase(unittest.HomeserverTestCase):
             access_token=self.other_user_token,
         )
 
-        self.assertEqual(
-            HTTPStatus.FORBIDDEN,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_media_does_not_exist(self) -> None:
         """
-        Tests that a lookup for a media that does not exist returns a HTTPStatus.NOT_FOUND
+        Tests that a lookup for a media that does not exist returns a 404
         """
         url = "/_synapse/admin/v1/media/%s/%s" % (self.server_name, "12345")
 
@@ -100,12 +95,12 @@ class DeleteMediaByIDTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     def test_media_is_not_local(self) -> None:
         """
-        Tests that a lookup for a media that is not a local returns a HTTPStatus.BAD_REQUEST
+        Tests that a lookup for a media that is not a local returns a 400
         """
         url = "/_synapse/admin/v1/media/%s/%s" % ("unknown_domain", "12345")
 
@@ -115,7 +110,7 @@ class DeleteMediaByIDTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Can only delete local media", channel.json_body["error"])
 
     def test_delete_media(self) -> None:
@@ -131,7 +126,7 @@ class DeleteMediaByIDTestCase(unittest.HomeserverTestCase):
             upload_resource,
             SMALL_PNG,
             tok=self.admin_user_tok,
-            expect_code=HTTPStatus.OK,
+            expect_code=200,
         )
         # Extract media ID from the response
         server_and_media_id = response["content_uri"][6:]  # Cut off 'mxc://'
@@ -151,11 +146,10 @@ class DeleteMediaByIDTestCase(unittest.HomeserverTestCase):
 
         # Should be successful
         self.assertEqual(
-            HTTPStatus.OK,
+            200,
             channel.code,
             msg=(
-                "Expected to receive a HTTPStatus.OK on accessing media: %s"
-                % server_and_media_id
+                "Expected to receive a 200 on accessing media: %s" % server_and_media_id
             ),
         )
 
@@ -172,7 +166,7 @@ class DeleteMediaByIDTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(1, channel.json_body["total"])
         self.assertEqual(
             media_id,
@@ -189,10 +183,10 @@ class DeleteMediaByIDTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
         self.assertEqual(
-            HTTPStatus.NOT_FOUND,
+            404,
             channel.code,
             msg=(
-                "Expected to receive a HTTPStatus.NOT_FOUND on accessing deleted media: %s"
+                "Expected to receive a 404 on accessing deleted media: %s"
                 % server_and_media_id
             ),
         )
@@ -231,11 +225,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
 
         channel = self.make_request("POST", self.url, b"{}")
 
-        self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_requester_is_no_admin(self) -> None:
@@ -251,16 +241,12 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             access_token=self.other_user_token,
         )
 
-        self.assertEqual(
-            HTTPStatus.FORBIDDEN,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_media_is_not_local(self) -> None:
         """
-        Tests that a lookup for media that is not local returns a HTTPStatus.BAD_REQUEST
+        Tests that a lookup for media that is not local returns a 400
         """
         url = "/_synapse/admin/v1/media/%s/delete" % "unknown_domain"
 
@@ -270,7 +256,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Can only delete local media", channel.json_body["error"])
 
     def test_missing_parameter(self) -> None:
@@ -283,11 +269,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_PARAM, channel.json_body["errcode"])
         self.assertEqual(
             "Missing integer query parameter 'before_ts'", channel.json_body["error"]
@@ -303,11 +285,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
         self.assertEqual(
             "Query parameter before_ts must be a positive integer.",
@@ -320,11 +298,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
         self.assertEqual(
             "Query parameter before_ts you provided is from the year 1970. "
@@ -338,11 +312,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
         self.assertEqual(
             "Query parameter size_gt must be a string representing a positive integer.",
@@ -355,11 +325,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
         self.assertEqual(
             "Boolean query parameter 'keep_profiles' must be one of ['true', 'false']",
@@ -388,7 +354,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             self.url + "?before_ts=" + str(now_ms),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(1, channel.json_body["total"])
         self.assertEqual(
             media_id,
@@ -413,7 +379,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             self.url + "?before_ts=" + str(now_ms),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(0, channel.json_body["total"])
 
         self._access_media(server_and_media_id)
@@ -425,7 +391,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             self.url + "?before_ts=" + str(now_ms),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(1, channel.json_body["total"])
         self.assertEqual(
             server_and_media_id.split("/")[1],
@@ -449,7 +415,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             self.url + "?before_ts=" + str(now_ms) + "&size_gt=67",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(0, channel.json_body["total"])
 
         self._access_media(server_and_media_id)
@@ -460,7 +426,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             self.url + "?before_ts=" + str(now_ms) + "&size_gt=66",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(1, channel.json_body["total"])
         self.assertEqual(
             server_and_media_id.split("/")[1],
@@ -485,7 +451,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             content={"avatar_url": "mxc://%s" % (server_and_media_id,)},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         now_ms = self.clock.time_msec()
         channel = self.make_request(
@@ -493,7 +459,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             self.url + "?before_ts=" + str(now_ms) + "&keep_profiles=true",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(0, channel.json_body["total"])
 
         self._access_media(server_and_media_id)
@@ -504,7 +470,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             self.url + "?before_ts=" + str(now_ms) + "&keep_profiles=false",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(1, channel.json_body["total"])
         self.assertEqual(
             server_and_media_id.split("/")[1],
@@ -530,7 +496,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             content={"url": "mxc://%s" % (server_and_media_id,)},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         now_ms = self.clock.time_msec()
         channel = self.make_request(
@@ -538,7 +504,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             self.url + "?before_ts=" + str(now_ms) + "&keep_profiles=true",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(0, channel.json_body["total"])
 
         self._access_media(server_and_media_id)
@@ -549,7 +515,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             self.url + "?before_ts=" + str(now_ms) + "&keep_profiles=false",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(1, channel.json_body["total"])
         self.assertEqual(
             server_and_media_id.split("/")[1],
@@ -569,7 +535,7 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             upload_resource,
             SMALL_PNG,
             tok=self.admin_user_tok,
-            expect_code=HTTPStatus.OK,
+            expect_code=200,
         )
         # Extract media ID from the response
         server_and_media_id = response["content_uri"][6:]  # Cut off 'mxc://'
@@ -602,10 +568,10 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
 
         if expect_success:
             self.assertEqual(
-                HTTPStatus.OK,
+                200,
                 channel.code,
                 msg=(
-                    "Expected to receive a HTTPStatus.OK on accessing media: %s"
+                    "Expected to receive a 200 on accessing media: %s"
                     % server_and_media_id
                 ),
             )
@@ -613,10 +579,10 @@ class DeleteMediaByDateSizeTestCase(unittest.HomeserverTestCase):
             self.assertTrue(os.path.exists(local_path))
         else:
             self.assertEqual(
-                HTTPStatus.NOT_FOUND,
+                404,
                 channel.code,
                 msg=(
-                    "Expected to receive a HTTPStatus.NOT_FOUND on accessing deleted media: %s"
+                    "Expected to receive a 404 on accessing deleted media: %s"
                     % (server_and_media_id)
                 ),
             )
@@ -648,7 +614,7 @@ class QuarantineMediaByIDTestCase(unittest.HomeserverTestCase):
             upload_resource,
             SMALL_PNG,
             tok=self.admin_user_tok,
-            expect_code=HTTPStatus.OK,
+            expect_code=200,
         )
         # Extract media ID from the response
         server_and_media_id = response["content_uri"][6:]  # Cut off 'mxc://'
@@ -668,11 +634,7 @@ class QuarantineMediaByIDTestCase(unittest.HomeserverTestCase):
             b"{}",
         )
 
-        self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     @parameterized.expand(["quarantine", "unquarantine"])
@@ -689,11 +651,7 @@ class QuarantineMediaByIDTestCase(unittest.HomeserverTestCase):
             access_token=self.other_user_token,
         )
 
-        self.assertEqual(
-            HTTPStatus.FORBIDDEN,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_quarantine_media(self) -> None:
@@ -712,7 +670,7 @@ class QuarantineMediaByIDTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertFalse(channel.json_body)
 
         media_info = self.get_success(self.store.get_local_media(self.media_id))
@@ -726,7 +684,7 @@ class QuarantineMediaByIDTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertFalse(channel.json_body)
 
         media_info = self.get_success(self.store.get_local_media(self.media_id))
@@ -753,7 +711,7 @@ class QuarantineMediaByIDTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertFalse(channel.json_body)
 
         # verify that is not in quarantine
@@ -785,7 +743,7 @@ class ProtectMediaByIDTestCase(unittest.HomeserverTestCase):
             upload_resource,
             SMALL_PNG,
             tok=self.admin_user_tok,
-            expect_code=HTTPStatus.OK,
+            expect_code=200,
         )
         # Extract media ID from the response
         server_and_media_id = response["content_uri"][6:]  # Cut off 'mxc://'
@@ -801,11 +759,7 @@ class ProtectMediaByIDTestCase(unittest.HomeserverTestCase):
 
         channel = self.make_request("POST", self.url % (action, self.media_id), b"{}")
 
-        self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     @parameterized.expand(["protect", "unprotect"])
@@ -822,11 +776,7 @@ class ProtectMediaByIDTestCase(unittest.HomeserverTestCase):
             access_token=self.other_user_token,
         )
 
-        self.assertEqual(
-            HTTPStatus.FORBIDDEN,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_protect_media(self) -> None:
@@ -845,7 +795,7 @@ class ProtectMediaByIDTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertFalse(channel.json_body)
 
         media_info = self.get_success(self.store.get_local_media(self.media_id))
@@ -859,7 +809,7 @@ class ProtectMediaByIDTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertFalse(channel.json_body)
 
         media_info = self.get_success(self.store.get_local_media(self.media_id))
@@ -895,7 +845,7 @@ class PurgeMediaCacheTestCase(unittest.HomeserverTestCase):
         channel = self.make_request("POST", self.url, b"{}")
 
         self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
+            401,
             channel.code,
             msg=channel.json_body,
         )
@@ -914,11 +864,7 @@ class PurgeMediaCacheTestCase(unittest.HomeserverTestCase):
             access_token=self.other_user_token,
         )
 
-        self.assertEqual(
-            HTTPStatus.FORBIDDEN,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_invalid_parameter(self) -> None:
@@ -931,11 +877,7 @@ class PurgeMediaCacheTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
         self.assertEqual(
             "Query parameter before_ts must be a positive integer.",
@@ -948,11 +890,7 @@ class PurgeMediaCacheTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
         self.assertEqual(
             "Query parameter before_ts you provided is from the year 1970. "
diff --git a/tests/rest/admin/test_registration_tokens.py b/tests/rest/admin/test_registration_tokens.py
index 8354250ec2..8f8abc21c7 100644
--- a/tests/rest/admin/test_registration_tokens.py
+++ b/tests/rest/admin/test_registration_tokens.py
@@ -13,7 +13,6 @@
 # limitations under the License.
 import random
 import string
-from http import HTTPStatus
 from typing import Optional
 
 from twisted.test.proto_helpers import MemoryReactor
@@ -74,11 +73,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
     def test_create_no_auth(self) -> None:
         """Try to create a token without authentication."""
         channel = self.make_request("POST", self.url + "/new", {})
-        self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_create_requester_not_admin(self) -> None:
@@ -89,11 +84,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {},
             access_token=self.other_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.FORBIDDEN,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_create_using_defaults(self) -> None:
@@ -105,7 +96,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(len(channel.json_body["token"]), 16)
         self.assertIsNone(channel.json_body["uses_allowed"])
         self.assertIsNone(channel.json_body["expiry_time"])
@@ -129,7 +120,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["token"], token)
         self.assertEqual(channel.json_body["uses_allowed"], 1)
         self.assertEqual(channel.json_body["expiry_time"], data["expiry_time"])
@@ -150,7 +141,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(len(channel.json_body["token"]), 16)
         self.assertIsNone(channel.json_body["uses_allowed"])
         self.assertIsNone(channel.json_body["expiry_time"])
@@ -168,11 +159,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
 
     def test_create_token_invalid_chars(self) -> None:
@@ -188,11 +175,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
 
     def test_create_token_already_exists(self) -> None:
@@ -207,7 +190,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             data,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel1.code, msg=channel1.json_body)
+        self.assertEqual(200, channel1.code, msg=channel1.json_body)
 
         channel2 = self.make_request(
             "POST",
@@ -215,7 +198,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             data,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel2.code, msg=channel2.json_body)
+        self.assertEqual(400, channel2.code, msg=channel2.json_body)
         self.assertEqual(channel2.json_body["errcode"], Codes.INVALID_PARAM)
 
     def test_create_unable_to_generate_token(self) -> None:
@@ -251,7 +234,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"uses_allowed": 0},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["uses_allowed"], 0)
 
         # Should fail with negative integer
@@ -262,7 +245,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
         self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
+            400,
             channel.code,
             msg=channel.json_body,
         )
@@ -275,11 +258,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"uses_allowed": 1.5},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
 
     def test_create_expiry_time(self) -> None:
@@ -291,11 +270,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"expiry_time": self.clock.time_msec() - 10000},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
 
         # Should fail with float
@@ -305,11 +280,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"expiry_time": self.clock.time_msec() + 1000000.5},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
 
     def test_create_length(self) -> None:
@@ -321,7 +292,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"length": 64},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(len(channel.json_body["token"]), 64)
 
         # Should fail with 0
@@ -331,11 +302,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"length": 0},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
 
         # Should fail with a negative integer
@@ -345,11 +312,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"length": -5},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
 
         # Should fail with a float
@@ -359,11 +322,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"length": 8.5},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
 
         # Should fail with 65
@@ -373,11 +332,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"length": 65},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
 
     # UPDATING
@@ -389,11 +344,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             self.url + "/1234",  # Token doesn't exist but that doesn't matter
             {},
         )
-        self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_update_requester_not_admin(self) -> None:
@@ -404,11 +355,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {},
             access_token=self.other_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.FORBIDDEN,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_update_non_existent(self) -> None:
@@ -420,11 +367,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.NOT_FOUND,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.NOT_FOUND)
 
     def test_update_uses_allowed(self) -> None:
@@ -439,7 +382,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"uses_allowed": 1},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["uses_allowed"], 1)
         self.assertIsNone(channel.json_body["expiry_time"])
 
@@ -450,7 +393,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"uses_allowed": 0},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["uses_allowed"], 0)
         self.assertIsNone(channel.json_body["expiry_time"])
 
@@ -461,7 +404,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"uses_allowed": None},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertIsNone(channel.json_body["uses_allowed"])
         self.assertIsNone(channel.json_body["expiry_time"])
 
@@ -472,11 +415,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"uses_allowed": 1.5},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
 
         # Should fail with a negative integer
@@ -486,11 +425,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"uses_allowed": -5},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
 
     def test_update_expiry_time(self) -> None:
@@ -506,7 +441,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"expiry_time": new_expiry_time},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["expiry_time"], new_expiry_time)
         self.assertIsNone(channel.json_body["uses_allowed"])
 
@@ -517,7 +452,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"expiry_time": None},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertIsNone(channel.json_body["expiry_time"])
         self.assertIsNone(channel.json_body["uses_allowed"])
 
@@ -529,11 +464,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"expiry_time": past_time},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
 
         # Should fail a float
@@ -543,11 +474,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {"expiry_time": new_expiry_time + 0.5},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
 
     def test_update_both(self) -> None:
@@ -568,7 +495,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["uses_allowed"], 1)
         self.assertEqual(channel.json_body["expiry_time"], new_expiry_time)
 
@@ -589,11 +516,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
 
     # DELETING
@@ -605,11 +528,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             self.url + "/1234",  # Token doesn't exist but that doesn't matter
             {},
         )
-        self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_delete_requester_not_admin(self) -> None:
@@ -620,11 +539,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {},
             access_token=self.other_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.FORBIDDEN,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_delete_non_existent(self) -> None:
@@ -636,11 +551,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.NOT_FOUND,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.NOT_FOUND)
 
     def test_delete(self) -> None:
@@ -655,7 +566,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
     # GETTING ONE
 
@@ -666,11 +577,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             self.url + "/1234",  # Token doesn't exist but that doesn't matter
             {},
         )
-        self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_get_requester_not_admin(self) -> None:
@@ -682,7 +589,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.other_user_tok,
         )
         self.assertEqual(
-            HTTPStatus.FORBIDDEN,
+            403,
             channel.code,
             msg=channel.json_body,
         )
@@ -697,11 +604,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.NOT_FOUND,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], Codes.NOT_FOUND)
 
     def test_get(self) -> None:
@@ -716,7 +619,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["token"], token)
         self.assertIsNone(channel.json_body["uses_allowed"])
         self.assertIsNone(channel.json_body["expiry_time"])
@@ -728,11 +631,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
     def test_list_no_auth(self) -> None:
         """Try to list tokens without authentication."""
         channel = self.make_request("GET", self.url, {})
-        self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_list_requester_not_admin(self) -> None:
@@ -743,11 +642,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             {},
             access_token=self.other_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.FORBIDDEN,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_list_all(self) -> None:
@@ -762,7 +657,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(len(channel.json_body["registration_tokens"]), 1)
         token_info = channel.json_body["registration_tokens"][0]
         self.assertEqual(token_info["token"], token)
@@ -780,11 +675,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
 
     def _test_list_query_parameter(self, valid: str) -> None:
         """Helper used to test both valid=true and valid=false."""
@@ -816,7 +707,7 @@ class ManageRegistrationTokensTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(len(channel.json_body["registration_tokens"]), 2)
         token_info_1 = channel.json_body["registration_tokens"][0]
         token_info_2 = channel.json_body["registration_tokens"][1]
diff --git a/tests/rest/admin/test_room.py b/tests/rest/admin/test_room.py
index 2526136ff8..fd6da557c1 100644
--- a/tests/rest/admin/test_room.py
+++ b/tests/rest/admin/test_room.py
@@ -12,7 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import urllib.parse
-from http import HTTPStatus
 from typing import List, Optional
 from unittest.mock import Mock
 
@@ -68,7 +67,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
 
     def test_requester_is_no_admin(self) -> None:
         """
-        If the user is not a server admin, an error HTTPStatus.FORBIDDEN is returned.
+        If the user is not a server admin, an error 403 is returned.
         """
 
         channel = self.make_request(
@@ -78,7 +77,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.other_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_room_does_not_exist(self) -> None:
@@ -94,11 +93,11 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
     def test_room_is_not_valid(self) -> None:
         """
-        Check that invalid room names, return an error HTTPStatus.BAD_REQUEST.
+        Check that invalid room names, return an error 400.
         """
         url = "/_synapse/admin/v1/rooms/%s" % "invalidroom"
 
@@ -109,7 +108,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(
             "invalidroom is not a legal room ID",
             channel.json_body["error"],
@@ -127,7 +126,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertIn("new_room_id", channel.json_body)
         self.assertIn("kicked_users", channel.json_body)
         self.assertIn("failed_to_kick_users", channel.json_body)
@@ -145,7 +144,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(
             "User must be our own: @not:exist.bla",
             channel.json_body["error"],
@@ -163,7 +162,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.BAD_JSON, channel.json_body["errcode"])
 
     def test_purge_is_not_bool(self) -> None:
@@ -178,7 +177,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.BAD_JSON, channel.json_body["errcode"])
 
     def test_purge_room_and_block(self) -> None:
@@ -202,7 +201,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(None, channel.json_body["new_room_id"])
         self.assertEqual(self.other_user, channel.json_body["kicked_users"][0])
         self.assertIn("failed_to_kick_users", channel.json_body)
@@ -233,7 +232,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(None, channel.json_body["new_room_id"])
         self.assertEqual(self.other_user, channel.json_body["kicked_users"][0])
         self.assertIn("failed_to_kick_users", channel.json_body)
@@ -265,7 +264,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(None, channel.json_body["new_room_id"])
         self.assertEqual(self.other_user, channel.json_body["kicked_users"][0])
         self.assertIn("failed_to_kick_users", channel.json_body)
@@ -296,7 +295,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
         )
 
         # The room is now blocked.
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self._is_blocked(room_id)
 
     def test_shutdown_room_consent(self) -> None:
@@ -319,7 +318,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
             self.room_id,
             body="foo",
             tok=self.other_user_tok,
-            expect_code=HTTPStatus.FORBIDDEN,
+            expect_code=403,
         )
 
         # Test that room is not purged
@@ -337,7 +336,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(self.other_user, channel.json_body["kicked_users"][0])
         self.assertIn("new_room_id", channel.json_body)
         self.assertIn("failed_to_kick_users", channel.json_body)
@@ -366,7 +365,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
             {"history_visibility": "world_readable"},
             access_token=self.other_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Test that room is not purged
         with self.assertRaises(AssertionError):
@@ -383,7 +382,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(self.other_user, channel.json_body["kicked_users"][0])
         self.assertIn("new_room_id", channel.json_body)
         self.assertIn("failed_to_kick_users", channel.json_body)
@@ -398,7 +397,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
         self._has_no_members(self.room_id)
 
         # Assert we can no longer peek into the room
-        self._assert_peek(self.room_id, expect_code=HTTPStatus.FORBIDDEN)
+        self._assert_peek(self.room_id, expect_code=403)
 
     def _is_blocked(self, room_id: str, expect: bool = True) -> None:
         """Assert that the room is blocked or not"""
@@ -494,7 +493,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
     )
     def test_requester_is_no_admin(self, method: str, url: str) -> None:
         """
-        If the user is not a server admin, an error HTTPStatus.FORBIDDEN is returned.
+        If the user is not a server admin, an error 403 is returned.
         """
 
         channel = self.make_request(
@@ -504,7 +503,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.other_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_room_does_not_exist(self) -> None:
@@ -522,7 +521,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertIn("delete_id", channel.json_body)
         delete_id = channel.json_body["delete_id"]
 
@@ -533,7 +532,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(1, len(channel.json_body["results"]))
         self.assertEqual("complete", channel.json_body["results"][0]["status"])
         self.assertEqual(delete_id, channel.json_body["results"][0]["delete_id"])
@@ -546,7 +545,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
     )
     def test_room_is_not_valid(self, method: str, url: str) -> None:
         """
-        Check that invalid room names, return an error HTTPStatus.BAD_REQUEST.
+        Check that invalid room names, return an error 400.
         """
 
         channel = self.make_request(
@@ -556,7 +555,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(
             "invalidroom is not a legal room ID",
             channel.json_body["error"],
@@ -574,7 +573,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertIn("delete_id", channel.json_body)
         delete_id = channel.json_body["delete_id"]
 
@@ -592,7 +591,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(
             "User must be our own: @not:exist.bla",
             channel.json_body["error"],
@@ -610,7 +609,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.BAD_JSON, channel.json_body["errcode"])
 
     def test_purge_is_not_bool(self) -> None:
@@ -625,7 +624,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.BAD_JSON, channel.json_body["errcode"])
 
     def test_delete_expired_status(self) -> None:
@@ -639,7 +638,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertIn("delete_id", channel.json_body)
         delete_id1 = channel.json_body["delete_id"]
 
@@ -654,7 +653,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertIn("delete_id", channel.json_body)
         delete_id2 = channel.json_body["delete_id"]
 
@@ -665,7 +664,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(2, len(channel.json_body["results"]))
         self.assertEqual("complete", channel.json_body["results"][0]["status"])
         self.assertEqual("complete", channel.json_body["results"][1]["status"])
@@ -682,7 +681,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(1, len(channel.json_body["results"]))
         self.assertEqual("complete", channel.json_body["results"][0]["status"])
         self.assertEqual(delete_id2, channel.json_body["results"][0]["delete_id"])
@@ -696,7 +695,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     def test_delete_same_room_twice(self) -> None:
@@ -722,9 +721,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST, second_channel.code, msg=second_channel.json_body
-        )
+        self.assertEqual(400, second_channel.code, msg=second_channel.json_body)
         self.assertEqual(Codes.UNKNOWN, second_channel.json_body["errcode"])
         self.assertEqual(
             f"History purge already in progress for {self.room_id}",
@@ -733,7 +730,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
 
         # get result of first call
         first_channel.await_result()
-        self.assertEqual(HTTPStatus.OK, first_channel.code, msg=first_channel.json_body)
+        self.assertEqual(200, first_channel.code, msg=first_channel.json_body)
         self.assertIn("delete_id", first_channel.json_body)
 
         # check status after finish the task
@@ -764,7 +761,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertIn("delete_id", channel.json_body)
         delete_id = channel.json_body["delete_id"]
 
@@ -795,7 +792,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertIn("delete_id", channel.json_body)
         delete_id = channel.json_body["delete_id"]
 
@@ -827,7 +824,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertIn("delete_id", channel.json_body)
         delete_id = channel.json_body["delete_id"]
 
@@ -858,7 +855,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             self.room_id,
             body="foo",
             tok=self.other_user_tok,
-            expect_code=HTTPStatus.FORBIDDEN,
+            expect_code=403,
         )
 
         # Test that room is not purged
@@ -876,7 +873,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertIn("delete_id", channel.json_body)
         delete_id = channel.json_body["delete_id"]
 
@@ -887,7 +884,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             self.url_status_by_room_id,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(1, len(channel.json_body["results"]))
 
         # Test that member has moved to new room
@@ -914,7 +911,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             content={"history_visibility": "world_readable"},
             access_token=self.other_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Test that room is not purged
         with self.assertRaises(AssertionError):
@@ -931,7 +928,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertIn("delete_id", channel.json_body)
         delete_id = channel.json_body["delete_id"]
 
@@ -942,7 +939,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             self.url_status_by_room_id,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(1, len(channel.json_body["results"]))
 
         # Test that member has moved to new room
@@ -955,7 +952,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
         self._has_no_members(self.room_id)
 
         # Assert we can no longer peek into the room
-        self._assert_peek(self.room_id, expect_code=HTTPStatus.FORBIDDEN)
+        self._assert_peek(self.room_id, expect_code=403)
 
     def _is_blocked(self, room_id: str, expect: bool = True) -> None:
         """Assert that the room is blocked or not"""
@@ -1026,9 +1023,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             self.url_status_by_room_id,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(
-            HTTPStatus.OK, channel_room_id.code, msg=channel_room_id.json_body
-        )
+        self.assertEqual(200, channel_room_id.code, msg=channel_room_id.json_body)
         self.assertEqual(1, len(channel_room_id.json_body["results"]))
         self.assertEqual(
             delete_id, channel_room_id.json_body["results"][0]["delete_id"]
@@ -1041,7 +1036,7 @@ class DeleteRoomV2TestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
         self.assertEqual(
-            HTTPStatus.OK,
+            200,
             channel_delete_id.code,
             msg=channel_delete_id.json_body,
         )
@@ -1100,7 +1095,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
         )
 
         # Check request completed successfully
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Check that response json body contains a "rooms" key
         self.assertTrue(
@@ -1186,7 +1181,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
                 url.encode("ascii"),
                 access_token=self.admin_user_tok,
             )
-            self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+            self.assertEqual(200, channel.code, msg=channel.json_body)
 
             self.assertTrue("rooms" in channel.json_body)
             for r in channel.json_body["rooms"]:
@@ -1226,7 +1221,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
             url.encode("ascii"),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
     def test_correct_room_attributes(self) -> None:
         """Test the correct attributes for a room are returned"""
@@ -1253,7 +1248,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
             {"room_id": room_id},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Set this new alias as the canonical alias for this room
         self.helper.send_state(
@@ -1285,7 +1280,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
             url.encode("ascii"),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Check that rooms were returned
         self.assertTrue("rooms" in channel.json_body)
@@ -1341,7 +1336,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
                 url.encode("ascii"),
                 access_token=self.admin_user_tok,
             )
-            self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+            self.assertEqual(200, channel.code, msg=channel.json_body)
 
             # Check that rooms were returned
             self.assertTrue("rooms" in channel.json_body)
@@ -1487,7 +1482,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
         def _search_test(
             expected_room_id: Optional[str],
             search_term: str,
-            expected_http_code: int = HTTPStatus.OK,
+            expected_http_code: int = 200,
         ) -> None:
             """Search for a room and check that the returned room's id is a match
 
@@ -1505,7 +1500,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
             )
             self.assertEqual(expected_http_code, channel.code, msg=channel.json_body)
 
-            if expected_http_code != HTTPStatus.OK:
+            if expected_http_code != 200:
                 return
 
             # Check that rooms were returned
@@ -1548,7 +1543,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
 
         _search_test(None, "foo")
         _search_test(None, "bar")
-        _search_test(None, "", expected_http_code=HTTPStatus.BAD_REQUEST)
+        _search_test(None, "", expected_http_code=400)
 
         # Test that the whole room id returns the room
         _search_test(room_id_1, room_id_1)
@@ -1585,7 +1580,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
             url.encode("ascii"),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(room_id, channel.json_body["rooms"][0].get("room_id"))
         self.assertEqual("ж", channel.json_body["rooms"][0].get("name"))
 
@@ -1618,7 +1613,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
             url.encode("ascii"),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         self.assertIn("room_id", channel.json_body)
         self.assertIn("name", channel.json_body)
@@ -1638,6 +1633,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
         self.assertIn("history_visibility", channel.json_body)
         self.assertIn("state_events", channel.json_body)
         self.assertIn("room_type", channel.json_body)
+        self.assertIn("forgotten", channel.json_body)
         self.assertEqual(room_id_1, channel.json_body["room_id"])
 
     def test_single_room_devices(self) -> None:
@@ -1650,7 +1646,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
             url.encode("ascii"),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(1, channel.json_body["joined_local_devices"])
 
         # Have another user join the room
@@ -1664,7 +1660,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
             url.encode("ascii"),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(2, channel.json_body["joined_local_devices"])
 
         # leave room
@@ -1676,7 +1672,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
             url.encode("ascii"),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(0, channel.json_body["joined_local_devices"])
 
     def test_room_members(self) -> None:
@@ -1707,7 +1703,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
             url.encode("ascii"),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         self.assertCountEqual(
             ["@admin:test", "@foo:test", "@bar:test"], channel.json_body["members"]
@@ -1720,7 +1716,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
             url.encode("ascii"),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         self.assertCountEqual(
             ["@admin:test", "@bar:test", "@foobar:test"], channel.json_body["members"]
@@ -1738,7 +1734,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
             url.encode("ascii"),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertIn("state", channel.json_body)
         # testing that the state events match is painful and not done here. We assume that
         # the create_room already does the right thing, so no need to verify that we got
@@ -1755,7 +1751,7 @@ class RoomTestCase(unittest.HomeserverTestCase):
             {"room_id": room_id},
             access_token=admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Set this new alias as the canonical alias for this room
         self.helper.send_state(
@@ -1772,6 +1768,21 @@ class RoomTestCase(unittest.HomeserverTestCase):
             tok=admin_user_tok,
         )
 
+    def test_get_joined_members_after_leave_room(self) -> None:
+        """Test that requesting room members after leaving the room raises a 403 error."""
+
+        # create the room
+        user = self.register_user("foo", "pass")
+        user_tok = self.login("foo", "pass")
+        room_id = self.helper.create_room_as(user, tok=user_tok)
+        self.helper.leave(room_id, user, tok=user_tok)
+
+        # delete the rooms and get joined roomed membership
+        url = f"/_matrix/client/r0/rooms/{room_id}/joined_members"
+        channel = self.make_request("GET", url.encode("ascii"), access_token=user_tok)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
+        self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
+
 
 class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
 
@@ -1798,7 +1809,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
 
     def test_requester_is_no_admin(self) -> None:
         """
-        If the user is not a server admin, an error HTTPStatus.FORBIDDEN is returned.
+        If the user is not a server admin, an error 403 is returned.
         """
 
         channel = self.make_request(
@@ -1808,7 +1819,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.second_tok,
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_invalid_parameter(self) -> None:
@@ -1823,12 +1834,12 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_PARAM, channel.json_body["errcode"])
 
     def test_local_user_does_not_exist(self) -> None:
         """
-        Tests that a lookup for a user that does not exist returns a HTTPStatus.NOT_FOUND
+        Tests that a lookup for a user that does not exist returns a 404
         """
 
         channel = self.make_request(
@@ -1838,7 +1849,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     def test_remote_user(self) -> None:
@@ -1853,7 +1864,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(
             "This endpoint can only be used with local users",
             channel.json_body["error"],
@@ -1861,7 +1872,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
 
     def test_room_does_not_exist(self) -> None:
         """
-        Check that unknown rooms/server return error HTTPStatus.NOT_FOUND.
+        Check that unknown rooms/server return error 404.
         """
         url = "/_synapse/admin/v1/join/!unknown:test"
 
@@ -1872,12 +1883,15 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
-        self.assertEqual("No known servers", channel.json_body["error"])
+        self.assertEqual(404, channel.code, msg=channel.json_body)
+        self.assertEqual(
+            "Can't join remote room because no servers that are in the room have been provided.",
+            channel.json_body["error"],
+        )
 
     def test_room_is_not_valid(self) -> None:
         """
-        Check that invalid room names, return an error HTTPStatus.BAD_REQUEST.
+        Check that invalid room names, return an error 400.
         """
         url = "/_synapse/admin/v1/join/invalidroom"
 
@@ -1888,7 +1902,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(
             "invalidroom was not legal room ID or room alias",
             channel.json_body["error"],
@@ -1906,7 +1920,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(self.public_room_id, channel.json_body["room_id"])
 
         # Validate if user is a member of the room
@@ -1916,7 +1930,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             "/_matrix/client/r0/joined_rooms",
             access_token=self.second_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(self.public_room_id, channel.json_body["joined_rooms"][0])
 
     def test_join_private_room_if_not_member(self) -> None:
@@ -1936,7 +1950,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_join_private_room_if_member(self) -> None:
@@ -1964,7 +1978,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             "/_matrix/client/r0/joined_rooms",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(private_room_id, channel.json_body["joined_rooms"][0])
 
         # Join user to room.
@@ -1977,7 +1991,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             content={"user_id": self.second_user_id},
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(private_room_id, channel.json_body["room_id"])
 
         # Validate if user is a member of the room
@@ -1987,7 +2001,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             "/_matrix/client/r0/joined_rooms",
             access_token=self.second_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(private_room_id, channel.json_body["joined_rooms"][0])
 
     def test_join_private_room_if_owner(self) -> None:
@@ -2007,7 +2021,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(private_room_id, channel.json_body["room_id"])
 
         # Validate if user is a member of the room
@@ -2017,7 +2031,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             "/_matrix/client/r0/joined_rooms",
             access_token=self.second_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(private_room_id, channel.json_body["joined_rooms"][0])
 
     def test_context_as_non_admin(self) -> None:
@@ -2051,7 +2065,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
                 % (room_id, events[midway]["event_id"]),
                 access_token=tok,
             )
-            self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+            self.assertEqual(403, channel.code, msg=channel.json_body)
             self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_context_as_admin(self) -> None:
@@ -2081,7 +2095,7 @@ class JoinAliasRoomTestCase(unittest.HomeserverTestCase):
             % (room_id, events[midway]["event_id"]),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(
             channel.json_body["event"]["event_id"], events[midway]["event_id"]
         )
@@ -2140,7 +2154,7 @@ class MakeRoomAdminTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Now we test that we can join the room and ban a user.
         self.helper.join(room_id, self.admin_user, tok=self.admin_user_tok)
@@ -2167,7 +2181,7 @@ class MakeRoomAdminTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Now we test that we can join the room (we should have received an
         # invite) and can ban a user.
@@ -2193,7 +2207,7 @@ class MakeRoomAdminTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Now we test that we can join the room and ban a user.
         self.helper.join(room_id, self.second_user_id, tok=self.second_tok)
@@ -2227,11 +2241,11 @@ class MakeRoomAdminTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        # We expect this to fail with a HTTPStatus.BAD_REQUEST as there are no room admins.
+        # We expect this to fail with a 400 as there are no room admins.
         #
         # (Note we assert the error message to ensure that it's not denied for
         # some other reason)
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(
             channel.json_body["error"],
             "No local admin user in room with power to update power levels.",
@@ -2261,7 +2275,7 @@ class BlockRoomTestCase(unittest.HomeserverTestCase):
 
     @parameterized.expand([("PUT",), ("GET",)])
     def test_requester_is_no_admin(self, method: str) -> None:
-        """If the user is not a server admin, an error HTTPStatus.FORBIDDEN is returned."""
+        """If the user is not a server admin, an error 403 is returned."""
 
         channel = self.make_request(
             method,
@@ -2270,12 +2284,12 @@ class BlockRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.other_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     @parameterized.expand([("PUT",), ("GET",)])
     def test_room_is_not_valid(self, method: str) -> None:
-        """Check that invalid room names, return an error HTTPStatus.BAD_REQUEST."""
+        """Check that invalid room names, return an error 400."""
 
         channel = self.make_request(
             method,
@@ -2284,7 +2298,7 @@ class BlockRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(
             "invalidroom is not a legal room ID",
             channel.json_body["error"],
@@ -2301,7 +2315,7 @@ class BlockRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.BAD_JSON, channel.json_body["errcode"])
 
         # `block` is not set
@@ -2312,7 +2326,7 @@ class BlockRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_PARAM, channel.json_body["errcode"])
 
         # no content is send
@@ -2322,7 +2336,7 @@ class BlockRoomTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_JSON, channel.json_body["errcode"])
 
     def test_block_room(self) -> None:
@@ -2336,7 +2350,7 @@ class BlockRoomTestCase(unittest.HomeserverTestCase):
                 content={"block": True},
                 access_token=self.admin_user_tok,
             )
-            self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+            self.assertEqual(200, channel.code, msg=channel.json_body)
             self.assertTrue(channel.json_body["block"])
             self._is_blocked(room_id, expect=True)
 
@@ -2360,7 +2374,7 @@ class BlockRoomTestCase(unittest.HomeserverTestCase):
                 content={"block": True},
                 access_token=self.admin_user_tok,
             )
-            self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+            self.assertEqual(200, channel.code, msg=channel.json_body)
             self.assertTrue(channel.json_body["block"])
             self._is_blocked(self.room_id, expect=True)
 
@@ -2376,7 +2390,7 @@ class BlockRoomTestCase(unittest.HomeserverTestCase):
                 content={"block": False},
                 access_token=self.admin_user_tok,
             )
-            self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+            self.assertEqual(200, channel.code, msg=channel.json_body)
             self.assertFalse(channel.json_body["block"])
             self._is_blocked(room_id, expect=False)
 
@@ -2400,7 +2414,7 @@ class BlockRoomTestCase(unittest.HomeserverTestCase):
                 content={"block": False},
                 access_token=self.admin_user_tok,
             )
-            self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+            self.assertEqual(200, channel.code, msg=channel.json_body)
             self.assertFalse(channel.json_body["block"])
             self._is_blocked(self.room_id, expect=False)
 
@@ -2415,7 +2429,7 @@ class BlockRoomTestCase(unittest.HomeserverTestCase):
                 self.url % room_id,
                 access_token=self.admin_user_tok,
             )
-            self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+            self.assertEqual(200, channel.code, msg=channel.json_body)
             self.assertTrue(channel.json_body["block"])
             self.assertEqual(self.other_user, channel.json_body["user_id"])
 
@@ -2439,7 +2453,7 @@ class BlockRoomTestCase(unittest.HomeserverTestCase):
                 self.url % room_id,
                 access_token=self.admin_user_tok,
             )
-            self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+            self.assertEqual(200, channel.code, msg=channel.json_body)
             self.assertFalse(channel.json_body["block"])
             self.assertNotIn("user_id", channel.json_body)
 
diff --git a/tests/rest/admin/test_server_notice.py b/tests/rest/admin/test_server_notice.py
index dbcba2663c..a2f347f666 100644
--- a/tests/rest/admin/test_server_notice.py
+++ b/tests/rest/admin/test_server_notice.py
@@ -11,7 +11,6 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from http import HTTPStatus
 from typing import List
 
 from twisted.test.proto_helpers import MemoryReactor
@@ -57,7 +56,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
         channel = self.make_request("POST", self.url)
 
         self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
+            401,
             channel.code,
             msg=channel.json_body,
         )
@@ -72,7 +71,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
         )
 
         self.assertEqual(
-            HTTPStatus.FORBIDDEN,
+            403,
             channel.code,
             msg=channel.json_body,
         )
@@ -80,7 +79,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
 
     @override_config({"server_notices": {"system_mxid_localpart": "notices"}})
     def test_user_does_not_exist(self) -> None:
-        """Tests that a lookup for a user that does not exist returns a HTTPStatus.NOT_FOUND"""
+        """Tests that a lookup for a user that does not exist returns a 404"""
         channel = self.make_request(
             "POST",
             self.url,
@@ -88,13 +87,13 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
             content={"user_id": "@unknown_person:test", "content": ""},
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     @override_config({"server_notices": {"system_mxid_localpart": "notices"}})
     def test_user_is_not_local(self) -> None:
         """
-        Tests that a lookup for a user that is not a local returns a HTTPStatus.BAD_REQUEST
+        Tests that a lookup for a user that is not a local returns a 400
         """
         channel = self.make_request(
             "POST",
@@ -106,7 +105,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
             },
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(
             "Server notices can only be sent to local users", channel.json_body["error"]
         )
@@ -122,7 +121,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_JSON, channel.json_body["errcode"])
 
         # no content
@@ -133,7 +132,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
             content={"user_id": self.other_user},
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_PARAM, channel.json_body["errcode"])
 
         # no body
@@ -144,7 +143,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
             content={"user_id": self.other_user, "content": ""},
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.UNKNOWN, channel.json_body["errcode"])
         self.assertEqual("'body' not in content", channel.json_body["error"])
 
@@ -156,10 +155,66 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
             content={"user_id": self.other_user, "content": {"body": ""}},
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.UNKNOWN, channel.json_body["errcode"])
         self.assertEqual("'msgtype' not in content", channel.json_body["error"])
 
+    @override_config(
+        {
+            "server_notices": {
+                "system_mxid_localpart": "notices",
+                "system_mxid_avatar_url": "somthingwrong",
+            },
+            "max_avatar_size": "10M",
+        }
+    )
+    def test_invalid_avatar_url(self) -> None:
+        """If avatar url in homeserver.yaml is invalid and
+        "check avatar size and mime type" is set, an error is returned.
+        TODO: Should be checked when reading the configuration."""
+        channel = self.make_request(
+            "POST",
+            self.url,
+            access_token=self.admin_user_tok,
+            content={
+                "user_id": self.other_user,
+                "content": {"msgtype": "m.text", "body": "test msg"},
+            },
+        )
+
+        self.assertEqual(500, channel.code, msg=channel.json_body)
+        self.assertEqual(Codes.UNKNOWN, channel.json_body["errcode"])
+
+    @override_config(
+        {
+            "server_notices": {
+                "system_mxid_localpart": "notices",
+                "system_mxid_display_name": "test display name",
+                "system_mxid_avatar_url": None,
+            },
+            "max_avatar_size": "10M",
+        }
+    )
+    def test_displayname_is_set_avatar_is_none(self) -> None:
+        """
+        Tests that sending a server notices is successfully,
+        if a display_name is set, avatar_url is `None` and
+        "check avatar size and mime type" is set.
+        """
+        channel = self.make_request(
+            "POST",
+            self.url,
+            access_token=self.admin_user_tok,
+            content={
+                "user_id": self.other_user,
+                "content": {"msgtype": "m.text", "body": "test msg"},
+            },
+        )
+        self.assertEqual(200, channel.code, msg=channel.json_body)
+
+        # user has one invite
+        self._check_invite_and_join_status(self.other_user, 1, 0)
+
     def test_server_notice_disabled(self) -> None:
         """Tests that server returns error if server notice is disabled"""
         channel = self.make_request(
@@ -172,7 +227,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
             },
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.UNKNOWN, channel.json_body["errcode"])
         self.assertEqual(
             "Server notices are not enabled on this server", channel.json_body["error"]
@@ -197,7 +252,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
                 "content": {"msgtype": "m.text", "body": "test msg one"},
             },
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # user has one invite
         invited_rooms = self._check_invite_and_join_status(self.other_user, 1, 0)
@@ -226,7 +281,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
                 "content": {"msgtype": "m.text", "body": "test msg two"},
             },
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # user has no new invites or memberships
         self._check_invite_and_join_status(self.other_user, 0, 1)
@@ -260,7 +315,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
                 "content": {"msgtype": "m.text", "body": "test msg one"},
             },
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # user has one invite
         invited_rooms = self._check_invite_and_join_status(self.other_user, 1, 0)
@@ -301,7 +356,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
                 "content": {"msgtype": "m.text", "body": "test msg two"},
             },
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # user has one invite
         invited_rooms = self._check_invite_and_join_status(self.other_user, 1, 0)
@@ -341,7 +396,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
                 "content": {"msgtype": "m.text", "body": "test msg one"},
             },
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # user has one invite
         invited_rooms = self._check_invite_and_join_status(self.other_user, 1, 0)
@@ -388,7 +443,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
                 "content": {"msgtype": "m.text", "body": "test msg two"},
             },
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # user has one invite
         invited_rooms = self._check_invite_and_join_status(self.other_user, 1, 0)
@@ -538,7 +593,7 @@ class ServerNoticeTestCase(unittest.HomeserverTestCase):
         channel = self.make_request(
             "GET", "/_matrix/client/r0/sync", access_token=token
         )
-        self.assertEqual(channel.code, HTTPStatus.OK)
+        self.assertEqual(channel.code, 200)
 
         # Get the messages
         room = channel.json_body["rooms"]["join"][room_id]
diff --git a/tests/rest/admin/test_statistics.py b/tests/rest/admin/test_statistics.py
index 7cb8ec57ba..b60f16b914 100644
--- a/tests/rest/admin/test_statistics.py
+++ b/tests/rest/admin/test_statistics.py
@@ -12,7 +12,6 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from http import HTTPStatus
 from typing import List, Optional
 
 from twisted.test.proto_helpers import MemoryReactor
@@ -51,16 +50,12 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
         """
         channel = self.make_request("GET", self.url, b"{}")
 
-        self.assertEqual(
-            HTTPStatus.UNAUTHORIZED,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_requester_is_no_admin(self) -> None:
         """
-        If the user is not a server admin, an error HTTPStatus.FORBIDDEN is returned.
+        If the user is not a server admin, an error 403 is returned.
         """
         channel = self.make_request(
             "GET",
@@ -69,11 +64,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.other_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.FORBIDDEN,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_invalid_parameter(self) -> None:
@@ -87,11 +78,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # negative from
@@ -101,11 +88,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # negative limit
@@ -115,11 +98,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # negative from_ts
@@ -129,11 +108,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # negative until_ts
@@ -143,11 +118,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # until_ts smaller from_ts
@@ -157,11 +128,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # empty search term
@@ -171,11 +138,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # invalid search order
@@ -185,11 +148,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
     def test_limit(self) -> None:
@@ -204,7 +163,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 10)
         self.assertEqual(len(channel.json_body["users"]), 5)
         self.assertEqual(channel.json_body["next_token"], 5)
@@ -222,7 +181,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 20)
         self.assertEqual(len(channel.json_body["users"]), 15)
         self.assertNotIn("next_token", channel.json_body)
@@ -240,7 +199,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 20)
         self.assertEqual(channel.json_body["next_token"], 15)
         self.assertEqual(len(channel.json_body["users"]), 10)
@@ -262,7 +221,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_users)
         self.assertEqual(len(channel.json_body["users"]), number_users)
         self.assertNotIn("next_token", channel.json_body)
@@ -275,7 +234,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_users)
         self.assertEqual(len(channel.json_body["users"]), number_users)
         self.assertNotIn("next_token", channel.json_body)
@@ -288,7 +247,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_users)
         self.assertEqual(len(channel.json_body["users"]), 19)
         self.assertEqual(channel.json_body["next_token"], 19)
@@ -301,7 +260,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_users)
         self.assertEqual(len(channel.json_body["users"]), 1)
         self.assertNotIn("next_token", channel.json_body)
@@ -318,7 +277,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(0, channel.json_body["total"])
         self.assertEqual(0, len(channel.json_body["users"]))
 
@@ -415,7 +374,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             self.url,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["users"][0]["media_count"], 3)
 
         # filter media starting at `ts1` after creating first media
@@ -425,7 +384,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             self.url + "?from_ts=%s" % (ts1,),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 0)
 
         self._create_media(self.other_user_tok, 3)
@@ -440,7 +399,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             self.url + "?from_ts=%s&until_ts=%s" % (ts1, ts2),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["users"][0]["media_count"], 3)
 
         # filter media until `ts2` and earlier
@@ -449,7 +408,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             self.url + "?until_ts=%s" % (ts2,),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["users"][0]["media_count"], 6)
 
     def test_search_term(self) -> None:
@@ -461,7 +420,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             self.url,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 20)
 
         # filter user 1 and 10-19 by `user_id`
@@ -470,7 +429,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             self.url + "?search_term=foo_user_1",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 11)
 
         # filter on this user in `displayname`
@@ -479,7 +438,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             self.url + "?search_term=bar_user_10",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["users"][0]["displayname"], "bar_user_10")
         self.assertEqual(channel.json_body["total"], 1)
 
@@ -489,7 +448,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             self.url + "?search_term=foobar",
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 0)
 
     def _create_users_with_media(self, number_users: int, media_per_user: int) -> None:
@@ -515,7 +474,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
         for _ in range(number_media):
             # Upload some media into the room
             self.helper.upload_media(
-                upload_resource, SMALL_PNG, tok=user_token, expect_code=HTTPStatus.OK
+                upload_resource, SMALL_PNG, tok=user_token, expect_code=200
             )
 
     def _check_fields(self, content: List[JsonDict]) -> None:
@@ -549,7 +508,7 @@ class UserMediaStatisticsTestCase(unittest.HomeserverTestCase):
             url.encode("ascii"),
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], len(expected_user_list))
 
         returned_order = [row["user_id"] for row in channel.json_body["users"]]
diff --git a/tests/rest/admin/test_user.py b/tests/rest/admin/test_user.py
index 12db68d564..1afd082707 100644
--- a/tests/rest/admin/test_user.py
+++ b/tests/rest/admin/test_user.py
@@ -1,4 +1,4 @@
-# Copyright 2018-2021 The Matrix.org Foundation C.I.C.
+# Copyright 2018-2022 The Matrix.org Foundation C.I.C.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -17,7 +17,6 @@ import hmac
 import os
 import urllib.parse
 from binascii import unhexlify
-from http import HTTPStatus
 from typing import List, Optional
 from unittest.mock import Mock, patch
 
@@ -79,7 +78,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
 
         channel = self.make_request("POST", self.url, b"{}")
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(
             "Shared secret registration is not enabled", channel.json_body["error"]
         )
@@ -111,7 +110,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         body = {"nonce": nonce}
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("username must be specified", channel.json_body["error"])
 
         # 61 seconds
@@ -119,7 +118,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
 
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("unrecognised nonce", channel.json_body["error"])
 
     def test_register_incorrect_nonce(self) -> None:
@@ -142,7 +141,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         }
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual("HMAC incorrect", channel.json_body["error"])
 
     def test_register_correct_nonce(self) -> None:
@@ -169,7 +168,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         }
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["user_id"])
 
     def test_nonce_reuse(self) -> None:
@@ -192,13 +191,13 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         }
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["user_id"])
 
         # Now, try and reuse it
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("unrecognised nonce", channel.json_body["error"])
 
     def test_missing_parts(self) -> None:
@@ -219,7 +218,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         # Must be an empty body present
         channel = self.make_request("POST", self.url, {})
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("nonce must be specified", channel.json_body["error"])
 
         #
@@ -229,28 +228,28 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         # Must be present
         channel = self.make_request("POST", self.url, {"nonce": nonce()})
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("username must be specified", channel.json_body["error"])
 
         # Must be a string
         body = {"nonce": nonce(), "username": 1234}
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Invalid username", channel.json_body["error"])
 
         # Must not have null bytes
         body = {"nonce": nonce(), "username": "abcd\u0000"}
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Invalid username", channel.json_body["error"])
 
         # Must not have null bytes
         body = {"nonce": nonce(), "username": "a" * 1000}
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Invalid username", channel.json_body["error"])
 
         #
@@ -261,28 +260,28 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         body = {"nonce": nonce(), "username": "a"}
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("password must be specified", channel.json_body["error"])
 
         # Must be a string
         body = {"nonce": nonce(), "username": "a", "password": 1234}
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Invalid password", channel.json_body["error"])
 
         # Must not have null bytes
         body = {"nonce": nonce(), "username": "a", "password": "abcd\u0000"}
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Invalid password", channel.json_body["error"])
 
         # Super long
         body = {"nonce": nonce(), "username": "a", "password": "A" * 1000}
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Invalid password", channel.json_body["error"])
 
         #
@@ -298,7 +297,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         }
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Invalid user type", channel.json_body["error"])
 
     def test_displayname(self) -> None:
@@ -323,11 +322,11 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
 
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@bob1:test", channel.json_body["user_id"])
 
         channel = self.make_request("GET", "/profile/@bob1:test/displayname")
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("bob1", channel.json_body["displayname"])
 
         # displayname is None
@@ -347,11 +346,11 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         }
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@bob2:test", channel.json_body["user_id"])
 
         channel = self.make_request("GET", "/profile/@bob2:test/displayname")
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("bob2", channel.json_body["displayname"])
 
         # displayname is empty
@@ -371,11 +370,11 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         }
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@bob3:test", channel.json_body["user_id"])
 
         channel = self.make_request("GET", "/profile/@bob3:test/displayname")
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
 
         # set displayname
         channel = self.make_request("GET", self.url)
@@ -394,11 +393,11 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         }
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@bob4:test", channel.json_body["user_id"])
 
         channel = self.make_request("GET", "/profile/@bob4:test/displayname")
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("Bob's Name", channel.json_body["displayname"])
 
     @override_config(
@@ -442,7 +441,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
         }
         channel = self.make_request("POST", self.url, body)
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["user_id"])
 
 
@@ -466,7 +465,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
         """
         channel = self.make_request("GET", self.url, b"{}")
 
-        self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_requester_is_no_admin(self) -> None:
@@ -478,7 +477,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
 
         channel = self.make_request("GET", self.url, access_token=other_user_token)
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_all_users(self) -> None:
@@ -494,7 +493,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(3, len(channel.json_body["users"]))
         self.assertEqual(3, channel.json_body["total"])
 
@@ -508,7 +507,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             expected_user_id: Optional[str],
             search_term: str,
             search_field: Optional[str] = "name",
-            expected_http_code: Optional[int] = HTTPStatus.OK,
+            expected_http_code: Optional[int] = 200,
         ) -> None:
             """Search for a user and check that the returned user's id is a match
 
@@ -530,7 +529,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             )
             self.assertEqual(expected_http_code, channel.code, msg=channel.json_body)
 
-            if expected_http_code != HTTPStatus.OK:
+            if expected_http_code != 200:
                 return
 
             # Check that users were returned
@@ -591,7 +590,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # negative from
@@ -601,7 +600,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # invalid guests
@@ -611,7 +610,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # invalid deactivated
@@ -621,7 +620,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # unkown order_by
@@ -631,7 +630,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # invalid search order
@@ -641,7 +640,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
     def test_limit(self) -> None:
@@ -659,7 +658,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_users)
         self.assertEqual(len(channel.json_body["users"]), 5)
         self.assertEqual(channel.json_body["next_token"], "5")
@@ -680,7 +679,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_users)
         self.assertEqual(len(channel.json_body["users"]), 15)
         self.assertNotIn("next_token", channel.json_body)
@@ -701,7 +700,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_users)
         self.assertEqual(channel.json_body["next_token"], "15")
         self.assertEqual(len(channel.json_body["users"]), 10)
@@ -724,7 +723,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_users)
         self.assertEqual(len(channel.json_body["users"]), number_users)
         self.assertNotIn("next_token", channel.json_body)
@@ -737,7 +736,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_users)
         self.assertEqual(len(channel.json_body["users"]), number_users)
         self.assertNotIn("next_token", channel.json_body)
@@ -750,7 +749,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_users)
         self.assertEqual(len(channel.json_body["users"]), 19)
         self.assertEqual(channel.json_body["next_token"], "19")
@@ -764,7 +763,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_users)
         self.assertEqual(len(channel.json_body["users"]), 1)
         self.assertNotIn("next_token", channel.json_body)
@@ -867,7 +866,7 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             url,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], len(expected_user_list))
 
         returned_order = [row["name"] for row in channel.json_body["users"]]
@@ -905,6 +904,96 @@ class UsersListTestCase(unittest.HomeserverTestCase):
             )
 
 
+class UserDevicesTestCase(unittest.HomeserverTestCase):
+    """
+    Tests user device management-related Admin APIs.
+    """
+
+    servlets = [
+        synapse.rest.admin.register_servlets,
+        login.register_servlets,
+        sync.register_servlets,
+    ]
+
+    def prepare(
+        self, reactor: MemoryReactor, clock: Clock, homeserver: HomeServer
+    ) -> None:
+        # Set up an Admin user to query the Admin API with.
+        self.admin_user_id = self.register_user("admin", "pass", admin=True)
+        self.admin_user_token = self.login("admin", "pass")
+
+        # Set up a test user to query the devices of.
+        self.other_user_device_id = "TESTDEVICEID"
+        self.other_user_device_display_name = "My Test Device"
+        self.other_user_client_ip = "1.2.3.4"
+        self.other_user_user_agent = "EquestriaTechnology/123.0"
+
+        self.other_user_id = self.register_user("user", "pass", displayname="User1")
+        self.other_user_token = self.login(
+            "user",
+            "pass",
+            device_id=self.other_user_device_id,
+            additional_request_fields={
+                "initial_device_display_name": self.other_user_device_display_name,
+            },
+        )
+
+        # Have the "other user" make a request so that the "last_seen_*" fields are
+        # populated in the tests below.
+        channel = self.make_request(
+            "GET",
+            "/_matrix/client/v3/sync",
+            access_token=self.other_user_token,
+            client_ip=self.other_user_client_ip,
+            custom_headers=[
+                ("User-Agent", self.other_user_user_agent),
+            ],
+        )
+        self.assertEqual(200, channel.code, msg=channel.json_body)
+
+    def test_list_user_devices(self) -> None:
+        """
+        Tests that a user's devices and attributes are listed correctly via the Admin API.
+        """
+        # Request all devices of "other user"
+        channel = self.make_request(
+            "GET",
+            f"/_synapse/admin/v2/users/{self.other_user_id}/devices",
+            access_token=self.admin_user_token,
+        )
+        self.assertEqual(200, channel.code, msg=channel.json_body)
+
+        # Double-check we got the single device expected
+        user_devices = channel.json_body["devices"]
+        self.assertEqual(len(user_devices), 1)
+        self.assertEqual(channel.json_body["total"], 1)
+
+        # Check that all the attributes of the device reported are as expected.
+        self._validate_attributes_of_device_response(user_devices[0])
+
+        # Request just a single device for "other user" by its ID
+        channel = self.make_request(
+            "GET",
+            f"/_synapse/admin/v2/users/{self.other_user_id}/devices/"
+            f"{self.other_user_device_id}",
+            access_token=self.admin_user_token,
+        )
+        self.assertEqual(200, channel.code, msg=channel.json_body)
+
+        # Check that all the attributes of the device reported are as expected.
+        self._validate_attributes_of_device_response(channel.json_body)
+
+    def _validate_attributes_of_device_response(self, response: JsonDict) -> None:
+        # Check that all device expected attributes are present
+        self.assertEqual(response["user_id"], self.other_user_id)
+        self.assertEqual(response["device_id"], self.other_user_device_id)
+        self.assertEqual(response["display_name"], self.other_user_device_display_name)
+        self.assertEqual(response["last_seen_ip"], self.other_user_client_ip)
+        self.assertEqual(response["last_seen_user_agent"], self.other_user_user_agent)
+        self.assertIsInstance(response["last_seen_ts"], int)
+        self.assertGreater(response["last_seen_ts"], 0)
+
+
 class DeactivateAccountTestCase(unittest.HomeserverTestCase):
 
     servlets = [
@@ -941,7 +1030,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
         """
         channel = self.make_request("POST", self.url, b"{}")
 
-        self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_requester_is_not_admin(self) -> None:
@@ -952,7 +1041,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
 
         channel = self.make_request("POST", url, access_token=self.other_user_token)
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual("You are not a server admin", channel.json_body["error"])
 
         channel = self.make_request(
@@ -962,12 +1051,12 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
             content=b"{}",
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual("You are not a server admin", channel.json_body["error"])
 
     def test_user_does_not_exist(self) -> None:
         """
-        Tests that deactivation for a user that does not exist returns a HTTPStatus.NOT_FOUND
+        Tests that deactivation for a user that does not exist returns a 404
         """
 
         channel = self.make_request(
@@ -976,7 +1065,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     def test_erase_is_not_bool(self) -> None:
@@ -991,18 +1080,18 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.BAD_JSON, channel.json_body["errcode"])
 
     def test_user_is_not_local(self) -> None:
         """
-        Tests that deactivation for a user that is not a local returns a HTTPStatus.BAD_REQUEST
+        Tests that deactivation for a user that is not a local returns a 400
         """
         url = "/_synapse/admin/v1/deactivate/@unknown_person:unknown_domain"
 
         channel = self.make_request("POST", url, access_token=self.admin_user_tok)
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Can only deactivate local users", channel.json_body["error"])
 
     def test_deactivate_user_erase_true(self) -> None:
@@ -1017,7 +1106,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(False, channel.json_body["deactivated"])
         self.assertEqual("foo@bar.com", channel.json_body["threepids"][0]["address"])
@@ -1032,7 +1121,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
             content={"erase": True},
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Get user
         channel = self.make_request(
@@ -1041,7 +1130,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(True, channel.json_body["deactivated"])
         self.assertEqual(0, len(channel.json_body["threepids"]))
@@ -1066,7 +1155,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"erase": True},
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self._is_erased("@user:test", True)
 
     def test_deactivate_user_erase_false(self) -> None:
@@ -1081,7 +1170,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(False, channel.json_body["deactivated"])
         self.assertEqual("foo@bar.com", channel.json_body["threepids"][0]["address"])
@@ -1096,7 +1185,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
             content={"erase": False},
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Get user
         channel = self.make_request(
@@ -1105,7 +1194,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(True, channel.json_body["deactivated"])
         self.assertEqual(0, len(channel.json_body["threepids"]))
@@ -1135,7 +1224,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(False, channel.json_body["deactivated"])
         self.assertEqual("foo@bar.com", channel.json_body["threepids"][0]["address"])
@@ -1150,7 +1239,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
             content={"erase": True},
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Get user
         channel = self.make_request(
@@ -1159,7 +1248,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(True, channel.json_body["deactivated"])
         self.assertEqual(0, len(channel.json_body["threepids"]))
@@ -1220,7 +1309,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.other_user_token,
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual("You are not a server admin", channel.json_body["error"])
 
         channel = self.make_request(
@@ -1230,12 +1319,12 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content=b"{}",
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual("You are not a server admin", channel.json_body["error"])
 
     def test_user_does_not_exist(self) -> None:
         """
-        Tests that a lookup for a user that does not exist returns a HTTPStatus.NOT_FOUND
+        Tests that a lookup for a user that does not exist returns a 404
         """
 
         channel = self.make_request(
@@ -1244,7 +1333,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual("M_NOT_FOUND", channel.json_body["errcode"])
 
     def test_invalid_parameter(self) -> None:
@@ -1259,7 +1348,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"admin": "not_bool"},
         )
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.BAD_JSON, channel.json_body["errcode"])
 
         # deactivated not bool
@@ -1269,7 +1358,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"deactivated": "not_bool"},
         )
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.UNKNOWN, channel.json_body["errcode"])
 
         # password not str
@@ -1279,7 +1368,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"password": True},
         )
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.UNKNOWN, channel.json_body["errcode"])
 
         # password not length
@@ -1289,7 +1378,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"password": "x" * 513},
         )
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.UNKNOWN, channel.json_body["errcode"])
 
         # user_type not valid
@@ -1299,7 +1388,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"user_type": "new type"},
         )
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.UNKNOWN, channel.json_body["errcode"])
 
         # external_ids not valid
@@ -1311,7 +1400,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
                 "external_ids": {"auth_provider": "prov", "wrong_external_id": "id"}
             },
         )
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_PARAM, channel.json_body["errcode"])
 
         channel = self.make_request(
@@ -1320,7 +1409,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"external_ids": {"external_id": "id"}},
         )
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_PARAM, channel.json_body["errcode"])
 
         # threepids not valid
@@ -1330,7 +1419,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"threepids": {"medium": "email", "wrong_address": "id"}},
         )
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_PARAM, channel.json_body["errcode"])
 
         channel = self.make_request(
@@ -1339,7 +1428,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"threepids": {"address": "value"}},
         )
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_PARAM, channel.json_body["errcode"])
 
     def test_get_user(self) -> None:
@@ -1352,7 +1441,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual("User", channel.json_body["displayname"])
         self._check_fields(channel.json_body)
@@ -1379,7 +1468,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content=body,
         )
 
-        self.assertEqual(HTTPStatus.CREATED, channel.code, msg=channel.json_body)
+        self.assertEqual(201, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["name"])
         self.assertEqual("Bob's name", channel.json_body["displayname"])
         self.assertEqual("email", channel.json_body["threepids"][0]["medium"])
@@ -1395,7 +1484,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["name"])
         self.assertEqual("Bob's name", channel.json_body["displayname"])
         self.assertEqual("email", channel.json_body["threepids"][0]["medium"])
@@ -1434,7 +1523,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content=body,
         )
 
-        self.assertEqual(HTTPStatus.CREATED, channel.code, msg=channel.json_body)
+        self.assertEqual(201, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["name"])
         self.assertEqual("Bob's name", channel.json_body["displayname"])
         self.assertEqual("email", channel.json_body["threepids"][0]["medium"])
@@ -1458,7 +1547,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["name"])
         self.assertEqual("Bob's name", channel.json_body["displayname"])
         self.assertEqual("email", channel.json_body["threepids"][0]["medium"])
@@ -1486,7 +1575,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         # before limit of monthly active users is reached
         channel = self.make_request("GET", "/sync", access_token=self.admin_user_tok)
 
-        if channel.code != HTTPStatus.OK:
+        if channel.code != 200:
             raise HttpResponseException(
                 channel.code, channel.result["reason"], channel.result["body"]
             )
@@ -1512,7 +1601,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content={"password": "abc123", "admin": False},
         )
 
-        self.assertEqual(HTTPStatus.CREATED, channel.code, msg=channel.json_body)
+        self.assertEqual(201, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["name"])
         self.assertFalse(channel.json_body["admin"])
 
@@ -1550,7 +1639,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         )
 
         # Admin user is not blocked by mau anymore
-        self.assertEqual(HTTPStatus.CREATED, channel.code, msg=channel.json_body)
+        self.assertEqual(201, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["name"])
         self.assertFalse(channel.json_body["admin"])
 
@@ -1585,7 +1674,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content=body,
         )
 
-        self.assertEqual(HTTPStatus.CREATED, channel.code, msg=channel.json_body)
+        self.assertEqual(201, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["name"])
         self.assertEqual("email", channel.json_body["threepids"][0]["medium"])
         self.assertEqual("bob@bob.bob", channel.json_body["threepids"][0]["address"])
@@ -1626,7 +1715,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content=body,
         )
 
-        self.assertEqual(HTTPStatus.CREATED, channel.code, msg=channel.json_body)
+        self.assertEqual(201, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["name"])
         self.assertEqual("email", channel.json_body["threepids"][0]["medium"])
         self.assertEqual("bob@bob.bob", channel.json_body["threepids"][0]["address"])
@@ -1666,7 +1755,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content=body,
         )
 
-        self.assertEqual(HTTPStatus.CREATED, channel.code, msg=channel.json_body)
+        self.assertEqual(201, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["name"])
         self.assertEqual("msisdn", channel.json_body["threepids"][0]["medium"])
         self.assertEqual("1234567890", channel.json_body["threepids"][0]["address"])
@@ -1684,7 +1773,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content={"password": "hahaha"},
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self._check_fields(channel.json_body)
 
     def test_set_displayname(self) -> None:
@@ -1700,7 +1789,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content={"displayname": "foobar"},
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual("foobar", channel.json_body["displayname"])
 
@@ -1711,7 +1800,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual("foobar", channel.json_body["displayname"])
 
@@ -1733,7 +1822,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             },
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(2, len(channel.json_body["threepids"]))
         # result does not always have the same sort order, therefore it becomes sorted
@@ -1759,7 +1848,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             },
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(2, len(channel.json_body["threepids"]))
         self.assertEqual("email", channel.json_body["threepids"][0]["medium"])
@@ -1775,7 +1864,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(2, len(channel.json_body["threepids"]))
         self.assertEqual("email", channel.json_body["threepids"][0]["medium"])
@@ -1791,7 +1880,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"threepids": []},
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(0, len(channel.json_body["threepids"]))
         self._check_fields(channel.json_body)
@@ -1818,7 +1907,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             },
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(first_user, channel.json_body["name"])
         self.assertEqual(1, len(channel.json_body["threepids"]))
         self.assertEqual("email", channel.json_body["threepids"][0]["medium"])
@@ -1837,7 +1926,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             },
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(1, len(channel.json_body["threepids"]))
         self.assertEqual("email", channel.json_body["threepids"][0]["medium"])
@@ -1859,7 +1948,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         )
 
         # other user has this two threepids
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(2, len(channel.json_body["threepids"]))
         # result does not always have the same sort order, therefore it becomes sorted
@@ -1878,7 +1967,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             url_first_user,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(first_user, channel.json_body["name"])
         self.assertEqual(0, len(channel.json_body["threepids"]))
         self._check_fields(channel.json_body)
@@ -1907,7 +1996,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             },
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(2, len(channel.json_body["external_ids"]))
         # result does not always have the same sort order, therefore it becomes sorted
@@ -1939,7 +2028,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             },
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(2, len(channel.json_body["external_ids"]))
         self.assertEqual(
@@ -1958,7 +2047,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(2, len(channel.json_body["external_ids"]))
         self.assertEqual(
@@ -1977,7 +2066,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"external_ids": []},
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(0, len(channel.json_body["external_ids"]))
 
@@ -2006,7 +2095,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             },
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(first_user, channel.json_body["name"])
         self.assertEqual(1, len(channel.json_body["external_ids"]))
         self.assertEqual(
@@ -2032,7 +2121,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             },
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(1, len(channel.json_body["external_ids"]))
         self.assertEqual(
@@ -2064,7 +2153,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         )
 
         # must fail
-        self.assertEqual(HTTPStatus.CONFLICT, channel.code, msg=channel.json_body)
+        self.assertEqual(409, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.UNKNOWN, channel.json_body["errcode"])
         self.assertEqual("External id is already in use.", channel.json_body["error"])
 
@@ -2075,7 +2164,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(1, len(channel.json_body["external_ids"]))
         self.assertEqual(
@@ -2093,7 +2182,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(first_user, channel.json_body["name"])
         self.assertEqual(1, len(channel.json_body["external_ids"]))
         self.assertEqual(
@@ -2124,7 +2213,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertFalse(channel.json_body["deactivated"])
         self.assertEqual("foo@bar.com", channel.json_body["threepids"][0]["address"])
@@ -2139,7 +2228,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content={"deactivated": True},
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertTrue(channel.json_body["deactivated"])
         self.assertEqual(0, len(channel.json_body["threepids"]))
@@ -2158,7 +2247,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertTrue(channel.json_body["deactivated"])
         self.assertEqual(0, len(channel.json_body["threepids"]))
@@ -2188,7 +2277,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content={"deactivated": True},
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertTrue(channel.json_body["deactivated"])
 
@@ -2204,7 +2293,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content={"displayname": "Foobar"},
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertTrue(channel.json_body["deactivated"])
         self.assertEqual("Foobar", channel.json_body["displayname"])
@@ -2228,7 +2317,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"deactivated": False},
         )
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
 
         # Reactivate the user.
         channel = self.make_request(
@@ -2237,7 +2326,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"deactivated": False, "password": "foo"},
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertFalse(channel.json_body["deactivated"])
         self._is_erased("@user:test", False)
@@ -2261,7 +2350,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"deactivated": False, "password": "foo"},
         )
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
         # Reactivate the user without a password.
@@ -2271,7 +2360,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"deactivated": False},
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertFalse(channel.json_body["deactivated"])
         self._is_erased("@user:test", False)
@@ -2295,7 +2384,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"deactivated": False, "password": "foo"},
         )
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
         # Reactivate the user without a password.
@@ -2305,7 +2394,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"deactivated": False},
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertFalse(channel.json_body["deactivated"])
         self._is_erased("@user:test", False)
@@ -2326,7 +2415,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content={"admin": True},
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertTrue(channel.json_body["admin"])
 
@@ -2337,7 +2426,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertTrue(channel.json_body["admin"])
 
@@ -2354,7 +2443,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content={"user_type": UserTypes.SUPPORT},
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(UserTypes.SUPPORT, channel.json_body["user_type"])
 
@@ -2365,7 +2454,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertEqual(UserTypes.SUPPORT, channel.json_body["user_type"])
 
@@ -2377,7 +2466,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content={"user_type": None},
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertIsNone(channel.json_body["user_type"])
 
@@ -2388,7 +2477,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@user:test", channel.json_body["name"])
         self.assertIsNone(channel.json_body["user_type"])
 
@@ -2407,7 +2496,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content={"password": "abc123"},
         )
 
-        self.assertEqual(HTTPStatus.CREATED, channel.code, msg=channel.json_body)
+        self.assertEqual(201, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["name"])
         self.assertEqual("bob", channel.json_body["displayname"])
 
@@ -2418,7 +2507,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["name"])
         self.assertEqual("bob", channel.json_body["displayname"])
         self.assertEqual(0, channel.json_body["deactivated"])
@@ -2431,7 +2520,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             content={"password": "abc123", "deactivated": "false"},
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
 
         # Check user is not deactivated
         channel = self.make_request(
@@ -2440,7 +2529,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual("@bob:test", channel.json_body["name"])
         self.assertEqual("bob", channel.json_body["displayname"])
 
@@ -2465,7 +2554,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"deactivated": True},
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertTrue(channel.json_body["deactivated"])
         self._is_erased(user_id, False)
         d = self.store.mark_user_erased(user_id)
@@ -2520,7 +2609,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
         """
         channel = self.make_request("GET", self.url, b"{}")
 
-        self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_requester_is_no_admin(self) -> None:
@@ -2535,7 +2624,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
             access_token=other_user_token,
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_user_does_not_exist(self) -> None:
@@ -2549,7 +2638,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(0, channel.json_body["total"])
         self.assertEqual(0, len(channel.json_body["joined_rooms"]))
 
@@ -2565,7 +2654,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(0, channel.json_body["total"])
         self.assertEqual(0, len(channel.json_body["joined_rooms"]))
 
@@ -2581,7 +2670,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(0, channel.json_body["total"])
         self.assertEqual(0, len(channel.json_body["joined_rooms"]))
 
@@ -2602,7 +2691,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(number_rooms, channel.json_body["total"])
         self.assertEqual(number_rooms, len(channel.json_body["joined_rooms"]))
 
@@ -2649,7 +2738,7 @@ class UserMembershipRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(1, channel.json_body["total"])
         self.assertEqual([local_and_remote_room_id], channel.json_body["joined_rooms"])
 
@@ -2678,7 +2767,7 @@ class PushersRestTestCase(unittest.HomeserverTestCase):
         """
         channel = self.make_request("GET", self.url, b"{}")
 
-        self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_requester_is_no_admin(self) -> None:
@@ -2693,12 +2782,12 @@ class PushersRestTestCase(unittest.HomeserverTestCase):
             access_token=other_user_token,
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_user_does_not_exist(self) -> None:
         """
-        Tests that a lookup for a user that does not exist returns a HTTPStatus.NOT_FOUND
+        Tests that a lookup for a user that does not exist returns a 404
         """
         url = "/_synapse/admin/v1/users/@unknown_person:test/pushers"
         channel = self.make_request(
@@ -2707,12 +2796,12 @@ class PushersRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     def test_user_is_not_local(self) -> None:
         """
-        Tests that a lookup for a user that is not a local returns a HTTPStatus.BAD_REQUEST
+        Tests that a lookup for a user that is not a local returns a 400
         """
         url = "/_synapse/admin/v1/users/@unknown_person:unknown_domain/pushers"
 
@@ -2722,7 +2811,7 @@ class PushersRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Can only look up local users", channel.json_body["error"])
 
     def test_get_pushers(self) -> None:
@@ -2737,7 +2826,7 @@ class PushersRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(0, channel.json_body["total"])
 
         # Register the pusher
@@ -2769,7 +2858,7 @@ class PushersRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(1, channel.json_body["total"])
 
         for p in channel.json_body["pushers"]:
@@ -2808,7 +2897,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         """Try to list media of an user without authentication."""
         channel = self.make_request(method, self.url, {})
 
-        self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     @parameterized.expand(["GET", "DELETE"])
@@ -2822,12 +2911,12 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=other_user_token,
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     @parameterized.expand(["GET", "DELETE"])
     def test_user_does_not_exist(self, method: str) -> None:
-        """Tests that a lookup for a user that does not exist returns a HTTPStatus.NOT_FOUND"""
+        """Tests that a lookup for a user that does not exist returns a 404"""
         url = "/_synapse/admin/v1/users/@unknown_person:test/media"
         channel = self.make_request(
             method,
@@ -2835,12 +2924,12 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     @parameterized.expand(["GET", "DELETE"])
     def test_user_is_not_local(self, method: str) -> None:
-        """Tests that a lookup for a user that is not a local returns a HTTPStatus.BAD_REQUEST"""
+        """Tests that a lookup for a user that is not a local returns a 400"""
         url = "/_synapse/admin/v1/users/@unknown_person:unknown_domain/media"
 
         channel = self.make_request(
@@ -2849,7 +2938,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Can only look up local users", channel.json_body["error"])
 
     def test_limit_GET(self) -> None:
@@ -2865,7 +2954,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_media)
         self.assertEqual(len(channel.json_body["media"]), 5)
         self.assertEqual(channel.json_body["next_token"], 5)
@@ -2884,7 +2973,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 5)
         self.assertEqual(len(channel.json_body["deleted_media"]), 5)
 
@@ -2901,7 +2990,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_media)
         self.assertEqual(len(channel.json_body["media"]), 15)
         self.assertNotIn("next_token", channel.json_body)
@@ -2920,7 +3009,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 15)
         self.assertEqual(len(channel.json_body["deleted_media"]), 15)
 
@@ -2937,7 +3026,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_media)
         self.assertEqual(channel.json_body["next_token"], 15)
         self.assertEqual(len(channel.json_body["media"]), 10)
@@ -2956,7 +3045,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], 10)
         self.assertEqual(len(channel.json_body["deleted_media"]), 10)
 
@@ -2970,7 +3059,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # invalid search order
@@ -2980,7 +3069,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # negative limit
@@ -2990,7 +3079,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # negative from
@@ -3000,7 +3089,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
     def test_next_token(self) -> None:
@@ -3023,7 +3112,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_media)
         self.assertEqual(len(channel.json_body["media"]), number_media)
         self.assertNotIn("next_token", channel.json_body)
@@ -3036,7 +3125,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_media)
         self.assertEqual(len(channel.json_body["media"]), number_media)
         self.assertNotIn("next_token", channel.json_body)
@@ -3049,7 +3138,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_media)
         self.assertEqual(len(channel.json_body["media"]), 19)
         self.assertEqual(channel.json_body["next_token"], 19)
@@ -3063,7 +3152,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], number_media)
         self.assertEqual(len(channel.json_body["media"]), 1)
         self.assertNotIn("next_token", channel.json_body)
@@ -3080,7 +3169,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(0, channel.json_body["total"])
         self.assertEqual(0, len(channel.json_body["media"]))
 
@@ -3095,7 +3184,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(0, channel.json_body["total"])
         self.assertEqual(0, len(channel.json_body["deleted_media"]))
 
@@ -3112,7 +3201,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(number_media, channel.json_body["total"])
         self.assertEqual(number_media, len(channel.json_body["media"]))
         self.assertNotIn("next_token", channel.json_body)
@@ -3138,7 +3227,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(number_media, channel.json_body["total"])
         self.assertEqual(number_media, len(channel.json_body["deleted_media"]))
         self.assertCountEqual(channel.json_body["deleted_media"], media_ids)
@@ -3283,7 +3372,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
 
         # Upload some media into the room
         response = self.helper.upload_media(
-            upload_resource, image_data, user_token, filename, expect_code=HTTPStatus.OK
+            upload_resource, image_data, user_token, filename, expect_code=200
         )
 
         # Extract media ID from the response
@@ -3301,10 +3390,10 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
         )
 
         self.assertEqual(
-            HTTPStatus.OK,
+            200,
             channel.code,
             msg=(
-                f"Expected to receive a HTTPStatus.OK on accessing media: {server_and_media_id}"
+                f"Expected to receive a 200 on accessing media: {server_and_media_id}"
             ),
         )
 
@@ -3350,7 +3439,7 @@ class UserMediaRestTestCase(unittest.HomeserverTestCase):
             url,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["total"], len(expected_media_list))
 
         returned_order = [row["media_id"] for row in channel.json_body["media"]]
@@ -3386,14 +3475,14 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
         channel = self.make_request(
             "POST", self.url, b"{}", access_token=self.admin_user_tok
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         return channel.json_body["access_token"]
 
     def test_no_auth(self) -> None:
         """Try to login as a user without authentication."""
         channel = self.make_request("POST", self.url, b"{}")
 
-        self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_not_admin(self) -> None:
@@ -3402,7 +3491,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
             "POST", self.url, b"{}", access_token=self.other_user_tok
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
 
     def test_send_event(self) -> None:
         """Test that sending event as a user works."""
@@ -3427,7 +3516,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
         channel = self.make_request(
             "GET", "devices", b"{}", access_token=self.other_user_tok
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # We should only see the one device (from the login in `prepare`)
         self.assertEqual(len(channel.json_body["devices"]), 1)
@@ -3439,21 +3528,21 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
 
         # Test that we can successfully make a request
         channel = self.make_request("GET", "devices", b"{}", access_token=puppet_token)
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Logout with the puppet token
         channel = self.make_request("POST", "logout", b"{}", access_token=puppet_token)
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # The puppet token should no longer work
         channel = self.make_request("GET", "devices", b"{}", access_token=puppet_token)
-        self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
+        self.assertEqual(401, channel.code, msg=channel.json_body)
 
         # .. but the real user's tokens should still work
         channel = self.make_request(
             "GET", "devices", b"{}", access_token=self.other_user_tok
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
     def test_user_logout_all(self) -> None:
         """Tests that the target user calling `/logout/all` does *not* expire
@@ -3464,23 +3553,23 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
 
         # Test that we can successfully make a request
         channel = self.make_request("GET", "devices", b"{}", access_token=puppet_token)
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Logout all with the real user token
         channel = self.make_request(
             "POST", "logout/all", b"{}", access_token=self.other_user_tok
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # The puppet token should still work
         channel = self.make_request("GET", "devices", b"{}", access_token=puppet_token)
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # .. but the real user's tokens shouldn't
         channel = self.make_request(
             "GET", "devices", b"{}", access_token=self.other_user_tok
         )
-        self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
+        self.assertEqual(401, channel.code, msg=channel.json_body)
 
     def test_admin_logout_all(self) -> None:
         """Tests that the admin user calling `/logout/all` does expire the
@@ -3491,23 +3580,23 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
 
         # Test that we can successfully make a request
         channel = self.make_request("GET", "devices", b"{}", access_token=puppet_token)
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # Logout all with the admin user token
         channel = self.make_request(
             "POST", "logout/all", b"{}", access_token=self.admin_user_tok
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
         # The puppet token should no longer work
         channel = self.make_request("GET", "devices", b"{}", access_token=puppet_token)
-        self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
+        self.assertEqual(401, channel.code, msg=channel.json_body)
 
         # .. but the real user's tokens should still work
         channel = self.make_request(
             "GET", "devices", b"{}", access_token=self.other_user_tok
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
 
     @unittest.override_config(
         {
@@ -3538,7 +3627,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
             room_id,
             "com.example.test",
             tok=self.other_user_tok,
-            expect_code=HTTPStatus.FORBIDDEN,
+            expect_code=403,
         )
 
         # Login in as the user
@@ -3559,7 +3648,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
             room_id,
             user=self.other_user,
             tok=self.other_user_tok,
-            expect_code=HTTPStatus.FORBIDDEN,
+            expect_code=403,
         )
 
         # Logging in as the other user and joining a room should work, even
@@ -3594,7 +3683,7 @@ class WhoisRestTestCase(unittest.HomeserverTestCase):
         Try to get information of an user without authentication.
         """
         channel = self.make_request("GET", self.url, b"{}")
-        self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_requester_is_not_admin(self) -> None:
@@ -3609,12 +3698,12 @@ class WhoisRestTestCase(unittest.HomeserverTestCase):
             self.url,
             access_token=other_user2_token,
         )
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_user_is_not_local(self) -> None:
         """
-        Tests that a lookup for a user that is not a local returns a HTTPStatus.BAD_REQUEST
+        Tests that a lookup for a user that is not a local returns a 400
         """
         url = self.url_prefix % "@unknown_person:unknown_domain"  # type: ignore[attr-defined]
 
@@ -3623,7 +3712,7 @@ class WhoisRestTestCase(unittest.HomeserverTestCase):
             url,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Can only whois a local user", channel.json_body["error"])
 
     def test_get_whois_admin(self) -> None:
@@ -3635,7 +3724,7 @@ class WhoisRestTestCase(unittest.HomeserverTestCase):
             self.url,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(self.other_user, channel.json_body["user_id"])
         self.assertIn("devices", channel.json_body)
 
@@ -3650,7 +3739,7 @@ class WhoisRestTestCase(unittest.HomeserverTestCase):
             self.url,
             access_token=other_user_token,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(self.other_user, channel.json_body["user_id"])
         self.assertIn("devices", channel.json_body)
 
@@ -3680,7 +3769,7 @@ class ShadowBanRestTestCase(unittest.HomeserverTestCase):
         Try to get information of an user without authentication.
         """
         channel = self.make_request(method, self.url)
-        self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     @parameterized.expand(["POST", "DELETE"])
@@ -3691,18 +3780,18 @@ class ShadowBanRestTestCase(unittest.HomeserverTestCase):
         other_user_token = self.login("user", "pass")
 
         channel = self.make_request(method, self.url, access_token=other_user_token)
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     @parameterized.expand(["POST", "DELETE"])
     def test_user_is_not_local(self, method: str) -> None:
         """
-        Tests that shadow-banning for a user that is not a local returns a HTTPStatus.BAD_REQUEST
+        Tests that shadow-banning for a user that is not a local returns a 400
         """
         url = "/_synapse/admin/v1/whois/@unknown_person:unknown_domain"
 
         channel = self.make_request(method, url, access_token=self.admin_user_tok)
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
 
     def test_success(self) -> None:
         """
@@ -3715,7 +3804,7 @@ class ShadowBanRestTestCase(unittest.HomeserverTestCase):
         self.assertFalse(result.shadow_banned)
 
         channel = self.make_request("POST", self.url, access_token=self.admin_user_tok)
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual({}, channel.json_body)
 
         # Ensure the user is shadow-banned (and the cache was cleared).
@@ -3727,7 +3816,7 @@ class ShadowBanRestTestCase(unittest.HomeserverTestCase):
         channel = self.make_request(
             "DELETE", self.url, access_token=self.admin_user_tok
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual({}, channel.json_body)
 
         # Ensure the user is no longer shadow-banned (and the cache was cleared).
@@ -3762,7 +3851,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
         """
         channel = self.make_request(method, self.url, b"{}")
 
-        self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     @parameterized.expand(["GET", "POST", "DELETE"])
@@ -3778,13 +3867,13 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             access_token=other_user_token,
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     @parameterized.expand(["GET", "POST", "DELETE"])
     def test_user_does_not_exist(self, method: str) -> None:
         """
-        Tests that a lookup for a user that does not exist returns a HTTPStatus.NOT_FOUND
+        Tests that a lookup for a user that does not exist returns a 404
         """
         url = "/_synapse/admin/v1/users/@unknown_person:test/override_ratelimit"
 
@@ -3794,7 +3883,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     @parameterized.expand(
@@ -3806,7 +3895,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
     )
     def test_user_is_not_local(self, method: str, error_msg: str) -> None:
         """
-        Tests that a lookup for a user that is not a local returns a HTTPStatus.BAD_REQUEST
+        Tests that a lookup for a user that is not a local returns a 400
         """
         url = (
             "/_synapse/admin/v1/users/@unknown_person:unknown_domain/override_ratelimit"
@@ -3818,7 +3907,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(error_msg, channel.json_body["error"])
 
     def test_invalid_parameter(self) -> None:
@@ -3833,7 +3922,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             content={"messages_per_second": "string"},
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # messages_per_second is negative
@@ -3844,7 +3933,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             content={"messages_per_second": -1},
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # burst_count is a string
@@ -3855,7 +3944,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             content={"burst_count": "string"},
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
         # burst_count is negative
@@ -3866,7 +3955,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             content={"burst_count": -1},
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.INVALID_PARAM, channel.json_body["errcode"])
 
     def test_return_zero_when_null(self) -> None:
@@ -3891,7 +3980,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             self.url,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(0, channel.json_body["messages_per_second"])
         self.assertEqual(0, channel.json_body["burst_count"])
 
@@ -3905,7 +3994,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             self.url,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertNotIn("messages_per_second", channel.json_body)
         self.assertNotIn("burst_count", channel.json_body)
 
@@ -3916,7 +4005,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"messages_per_second": 10, "burst_count": 11},
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(10, channel.json_body["messages_per_second"])
         self.assertEqual(11, channel.json_body["burst_count"])
 
@@ -3927,7 +4016,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
             content={"messages_per_second": 20, "burst_count": 21},
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(20, channel.json_body["messages_per_second"])
         self.assertEqual(21, channel.json_body["burst_count"])
 
@@ -3937,7 +4026,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             self.url,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(20, channel.json_body["messages_per_second"])
         self.assertEqual(21, channel.json_body["burst_count"])
 
@@ -3947,7 +4036,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             self.url,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertNotIn("messages_per_second", channel.json_body)
         self.assertNotIn("burst_count", channel.json_body)
 
@@ -3957,7 +4046,7 @@ class RateLimitTestCase(unittest.HomeserverTestCase):
             self.url,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertNotIn("messages_per_second", channel.json_body)
         self.assertNotIn("burst_count", channel.json_body)
 
@@ -3982,7 +4071,7 @@ class AccountDataTestCase(unittest.HomeserverTestCase):
         """Try to get information of a user without authentication."""
         channel = self.make_request("GET", self.url, {})
 
-        self.assertEqual(HTTPStatus.UNAUTHORIZED, channel.code, msg=channel.json_body)
+        self.assertEqual(401, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
 
     def test_requester_is_no_admin(self) -> None:
@@ -3995,7 +4084,7 @@ class AccountDataTestCase(unittest.HomeserverTestCase):
             access_token=other_user_token,
         )
 
-        self.assertEqual(HTTPStatus.FORBIDDEN, channel.code, msg=channel.json_body)
+        self.assertEqual(403, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
 
     def test_user_does_not_exist(self) -> None:
@@ -4008,7 +4097,7 @@ class AccountDataTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.NOT_FOUND, channel.code, msg=channel.json_body)
+        self.assertEqual(404, channel.code, msg=channel.json_body)
         self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
 
     def test_user_is_not_local(self) -> None:
@@ -4021,7 +4110,7 @@ class AccountDataTestCase(unittest.HomeserverTestCase):
             access_token=self.admin_user_tok,
         )
 
-        self.assertEqual(HTTPStatus.BAD_REQUEST, channel.code, msg=channel.json_body)
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual("Can only look up local users", channel.json_body["error"])
 
     def test_success(self) -> None:
@@ -4042,7 +4131,7 @@ class AccountDataTestCase(unittest.HomeserverTestCase):
             self.url,
             access_token=self.admin_user_tok,
         )
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertEqual(
             {"a": 1}, channel.json_body["account_data"]["global"]["m.global"]
         )
diff --git a/tests/rest/admin/test_username_available.py b/tests/rest/admin/test_username_available.py
index b21f6d4689..30f12f1bff 100644
--- a/tests/rest/admin/test_username_available.py
+++ b/tests/rest/admin/test_username_available.py
@@ -11,9 +11,6 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-
-from http import HTTPStatus
-
 from twisted.test.proto_helpers import MemoryReactor
 
 import synapse.rest.admin
@@ -40,7 +37,7 @@ class UsernameAvailableTestCase(unittest.HomeserverTestCase):
             if username == "allowed":
                 return True
             raise SynapseError(
-                HTTPStatus.BAD_REQUEST,
+                400,
                 "User ID already taken.",
                 errcode=Codes.USER_IN_USE,
             )
@@ -50,27 +47,23 @@ class UsernameAvailableTestCase(unittest.HomeserverTestCase):
 
     def test_username_available(self) -> None:
         """
-        The endpoint should return a HTTPStatus.OK response if the username does not exist
+        The endpoint should return a 200 response if the username does not exist
         """
 
         url = "%s?username=%s" % (self.url, "allowed")
         channel = self.make_request("GET", url, access_token=self.admin_user_tok)
 
-        self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.json_body)
+        self.assertEqual(200, channel.code, msg=channel.json_body)
         self.assertTrue(channel.json_body["available"])
 
     def test_username_unavailable(self) -> None:
         """
-        The endpoint should return a HTTPStatus.OK response if the username does not exist
+        The endpoint should return a 200 response if the username does not exist
         """
 
         url = "%s?username=%s" % (self.url, "disallowed")
         channel = self.make_request("GET", url, access_token=self.admin_user_tok)
 
-        self.assertEqual(
-            HTTPStatus.BAD_REQUEST,
-            channel.code,
-            msg=channel.json_body,
-        )
+        self.assertEqual(400, channel.code, msg=channel.json_body)
         self.assertEqual(channel.json_body["errcode"], "M_USER_IN_USE")
         self.assertEqual(channel.json_body["error"], "User ID already taken.")
diff --git a/tests/rest/client/test_account.py b/tests/rest/client/test_account.py
index 7ae926dc9c..c1a7fb2f8a 100644
--- a/tests/rest/client/test_account.py
+++ b/tests/rest/client/test_account.py
@@ -488,7 +488,7 @@ class DeactivateTestCase(unittest.HomeserverTestCase):
         channel = self.make_request(
             "POST", "account/deactivate", request_data, access_token=tok
         )
-        self.assertEqual(channel.code, 200)
+        self.assertEqual(channel.code, 200, channel.json_body)
 
 
 class WhoamiTestCase(unittest.HomeserverTestCase):
@@ -641,21 +641,21 @@ class ThreepidEmailRestTestCase(unittest.HomeserverTestCase):
     def test_add_email_no_at(self) -> None:
         self._request_token_invalid_email(
             "address-without-at.bar",
-            expected_errcode=Codes.UNKNOWN,
+            expected_errcode=Codes.BAD_JSON,
             expected_error="Unable to parse email address",
         )
 
     def test_add_email_two_at(self) -> None:
         self._request_token_invalid_email(
             "foo@foo@test.bar",
-            expected_errcode=Codes.UNKNOWN,
+            expected_errcode=Codes.BAD_JSON,
             expected_error="Unable to parse email address",
         )
 
     def test_add_email_bad_format(self) -> None:
         self._request_token_invalid_email(
             "user@bad.example.net@good.example.com",
-            expected_errcode=Codes.UNKNOWN,
+            expected_errcode=Codes.BAD_JSON,
             expected_error="Unable to parse email address",
         )
 
@@ -1001,7 +1001,7 @@ class ThreepidEmailRestTestCase(unittest.HomeserverTestCase):
             HTTPStatus.BAD_REQUEST, channel.code, msg=channel.result["body"]
         )
         self.assertEqual(expected_errcode, channel.json_body["errcode"])
-        self.assertEqual(expected_error, channel.json_body["error"])
+        self.assertIn(expected_error, channel.json_body["error"])
 
     def _validate_token(self, link: str) -> None:
         # Remove the host
diff --git a/tests/rest/client/test_filter.py b/tests/rest/client/test_filter.py
index 823e8ab8c4..afc8d641be 100644
--- a/tests/rest/client/test_filter.py
+++ b/tests/rest/client/test_filter.py
@@ -43,7 +43,7 @@ class FilterTestCase(unittest.HomeserverTestCase):
             self.EXAMPLE_FILTER_JSON,
         )
 
-        self.assertEqual(channel.result["code"], b"200")
+        self.assertEqual(channel.code, 200)
         self.assertEqual(channel.json_body, {"filter_id": "0"})
         filter = self.get_success(
             self.store.get_user_filter(user_localpart="apple", filter_id=0)
@@ -58,7 +58,7 @@ class FilterTestCase(unittest.HomeserverTestCase):
             self.EXAMPLE_FILTER_JSON,
         )
 
-        self.assertEqual(channel.result["code"], b"403")
+        self.assertEqual(channel.code, 403)
         self.assertEqual(channel.json_body["errcode"], Codes.FORBIDDEN)
 
     def test_add_filter_non_local_user(self) -> None:
@@ -71,7 +71,7 @@ class FilterTestCase(unittest.HomeserverTestCase):
         )
 
         self.hs.is_mine = _is_mine
-        self.assertEqual(channel.result["code"], b"403")
+        self.assertEqual(channel.code, 403)
         self.assertEqual(channel.json_body["errcode"], Codes.FORBIDDEN)
 
     def test_get_filter(self) -> None:
@@ -85,7 +85,7 @@ class FilterTestCase(unittest.HomeserverTestCase):
             "GET", "/_matrix/client/r0/user/%s/filter/%s" % (self.user_id, filter_id)
         )
 
-        self.assertEqual(channel.result["code"], b"200")
+        self.assertEqual(channel.code, 200)
         self.assertEqual(channel.json_body, self.EXAMPLE_FILTER)
 
     def test_get_filter_non_existant(self) -> None:
@@ -93,7 +93,7 @@ class FilterTestCase(unittest.HomeserverTestCase):
             "GET", "/_matrix/client/r0/user/%s/filter/12382148321" % (self.user_id)
         )
 
-        self.assertEqual(channel.result["code"], b"404")
+        self.assertEqual(channel.code, 404)
         self.assertEqual(channel.json_body["errcode"], Codes.NOT_FOUND)
 
     # Currently invalid params do not have an appropriate errcode
@@ -103,7 +103,7 @@ class FilterTestCase(unittest.HomeserverTestCase):
             "GET", "/_matrix/client/r0/user/%s/filter/foobar" % (self.user_id)
         )
 
-        self.assertEqual(channel.result["code"], b"400")
+        self.assertEqual(channel.code, 400)
 
     # No ID also returns an invalid_id error
     def test_get_filter_no_id(self) -> None:
@@ -111,4 +111,4 @@ class FilterTestCase(unittest.HomeserverTestCase):
             "GET", "/_matrix/client/r0/user/%s/filter/" % (self.user_id)
         )
 
-        self.assertEqual(channel.result["code"], b"400")
+        self.assertEqual(channel.code, 400)
diff --git a/tests/rest/client/test_login.py b/tests/rest/client/test_login.py
index a2958f6959..e2a4d98275 100644
--- a/tests/rest/client/test_login.py
+++ b/tests/rest/client/test_login.py
@@ -13,7 +13,6 @@
 # limitations under the License.
 import time
 import urllib.parse
-from http import HTTPStatus
 from typing import Any, Dict, List, Optional
 from unittest.mock import Mock
 from urllib.parse import urlencode
@@ -134,10 +133,10 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
             channel = self.make_request(b"POST", LOGIN_URL, params)
 
             if i == 5:
-                self.assertEqual(channel.result["code"], b"429", channel.result)
+                self.assertEqual(channel.code, 429, msg=channel.result)
                 retry_after_ms = int(channel.json_body["retry_after_ms"])
             else:
-                self.assertEqual(channel.result["code"], b"200", channel.result)
+                self.assertEqual(channel.code, 200, msg=channel.result)
 
         # Since we're ratelimiting at 1 request/min, retry_after_ms should be lower
         # than 1min.
@@ -152,7 +151,7 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
         }
         channel = self.make_request(b"POST", LOGIN_URL, params)
 
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
     @override_config(
         {
@@ -179,10 +178,10 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
             channel = self.make_request(b"POST", LOGIN_URL, params)
 
             if i == 5:
-                self.assertEqual(channel.result["code"], b"429", channel.result)
+                self.assertEqual(channel.code, 429, msg=channel.result)
                 retry_after_ms = int(channel.json_body["retry_after_ms"])
             else:
-                self.assertEqual(channel.result["code"], b"200", channel.result)
+                self.assertEqual(channel.code, 200, msg=channel.result)
 
         # Since we're ratelimiting at 1 request/min, retry_after_ms should be lower
         # than 1min.
@@ -197,7 +196,7 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
         }
         channel = self.make_request(b"POST", LOGIN_URL, params)
 
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
     @override_config(
         {
@@ -224,10 +223,10 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
             channel = self.make_request(b"POST", LOGIN_URL, params)
 
             if i == 5:
-                self.assertEqual(channel.result["code"], b"429", channel.result)
+                self.assertEqual(channel.code, 429, msg=channel.result)
                 retry_after_ms = int(channel.json_body["retry_after_ms"])
             else:
-                self.assertEqual(channel.result["code"], b"403", channel.result)
+                self.assertEqual(channel.code, 403, msg=channel.result)
 
         # Since we're ratelimiting at 1 request/min, retry_after_ms should be lower
         # than 1min.
@@ -242,7 +241,7 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
         }
         channel = self.make_request(b"POST", LOGIN_URL, params)
 
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
 
     @override_config({"session_lifetime": "24h"})
     def test_soft_logout(self) -> None:
@@ -250,7 +249,7 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
 
         # we shouldn't be able to make requests without an access token
         channel = self.make_request(b"GET", TEST_URL)
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_MISSING_TOKEN")
 
         # log in as normal
@@ -261,20 +260,20 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
         }
         channel = self.make_request(b"POST", LOGIN_URL, params)
 
-        self.assertEqual(channel.code, HTTPStatus.OK, channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
         access_token = channel.json_body["access_token"]
         device_id = channel.json_body["device_id"]
 
         # we should now be able to make requests with the access token
         channel = self.make_request(b"GET", TEST_URL, access_token=access_token)
-        self.assertEqual(channel.code, HTTPStatus.OK, channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
 
         # time passes
         self.reactor.advance(24 * 3600)
 
         # ... and we should be soft-logouted
         channel = self.make_request(b"GET", TEST_URL, access_token=access_token)
-        self.assertEqual(channel.code, HTTPStatus.UNAUTHORIZED, channel.result)
+        self.assertEqual(channel.code, 401, channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_UNKNOWN_TOKEN")
         self.assertEqual(channel.json_body["soft_logout"], True)
 
@@ -288,7 +287,7 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
         # more requests with the expired token should still return a soft-logout
         self.reactor.advance(3600)
         channel = self.make_request(b"GET", TEST_URL, access_token=access_token)
-        self.assertEqual(channel.code, HTTPStatus.UNAUTHORIZED, channel.result)
+        self.assertEqual(channel.code, 401, channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_UNKNOWN_TOKEN")
         self.assertEqual(channel.json_body["soft_logout"], True)
 
@@ -296,7 +295,7 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
         self._delete_device(access_token_2, "kermit", "monkey", device_id)
 
         channel = self.make_request(b"GET", TEST_URL, access_token=access_token)
-        self.assertEqual(channel.code, HTTPStatus.UNAUTHORIZED, channel.result)
+        self.assertEqual(channel.code, 401, channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_UNKNOWN_TOKEN")
         self.assertEqual(channel.json_body["soft_logout"], False)
 
@@ -307,7 +306,7 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
         channel = self.make_request(
             b"DELETE", "devices/" + device_id, access_token=access_token
         )
-        self.assertEqual(channel.code, HTTPStatus.UNAUTHORIZED, channel.result)
+        self.assertEqual(channel.code, 401, channel.result)
         # check it's a UI-Auth fail
         self.assertEqual(
             set(channel.json_body.keys()),
@@ -330,7 +329,7 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
             access_token=access_token,
             content={"auth": auth},
         )
-        self.assertEqual(channel.code, HTTPStatus.OK, channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
 
     @override_config({"session_lifetime": "24h"})
     def test_session_can_hard_logout_after_being_soft_logged_out(self) -> None:
@@ -341,20 +340,20 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
 
         # we should now be able to make requests with the access token
         channel = self.make_request(b"GET", TEST_URL, access_token=access_token)
-        self.assertEqual(channel.code, HTTPStatus.OK, channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
 
         # time passes
         self.reactor.advance(24 * 3600)
 
         # ... and we should be soft-logouted
         channel = self.make_request(b"GET", TEST_URL, access_token=access_token)
-        self.assertEqual(channel.code, HTTPStatus.UNAUTHORIZED, channel.result)
+        self.assertEqual(channel.code, 401, channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_UNKNOWN_TOKEN")
         self.assertEqual(channel.json_body["soft_logout"], True)
 
         # Now try to hard logout this session
         channel = self.make_request(b"POST", "/logout", access_token=access_token)
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
     @override_config({"session_lifetime": "24h"})
     def test_session_can_hard_logout_all_sessions_after_being_soft_logged_out(
@@ -367,20 +366,20 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
 
         # we should now be able to make requests with the access token
         channel = self.make_request(b"GET", TEST_URL, access_token=access_token)
-        self.assertEqual(channel.code, HTTPStatus.OK, channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
 
         # time passes
         self.reactor.advance(24 * 3600)
 
         # ... and we should be soft-logouted
         channel = self.make_request(b"GET", TEST_URL, access_token=access_token)
-        self.assertEqual(channel.code, HTTPStatus.UNAUTHORIZED, channel.result)
+        self.assertEqual(channel.code, 401, channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_UNKNOWN_TOKEN")
         self.assertEqual(channel.json_body["soft_logout"], True)
 
         # Now try to hard log out all of the user's sessions
         channel = self.make_request(b"POST", "/logout/all", access_token=access_token)
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
     def test_login_with_overly_long_device_id_fails(self) -> None:
         self.register_user("mickey", "cheese")
@@ -466,7 +465,7 @@ class MultiSSOTestCase(unittest.HomeserverTestCase):
     def test_get_login_flows(self) -> None:
         """GET /login should return password and SSO flows"""
         channel = self.make_request("GET", "/_matrix/client/r0/login")
-        self.assertEqual(channel.code, HTTPStatus.OK, channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
 
         expected_flow_types = [
             "m.login.cas",
@@ -494,14 +493,14 @@ class MultiSSOTestCase(unittest.HomeserverTestCase):
         """/login/sso/redirect should redirect to an identity picker"""
         # first hit the redirect url, which should redirect to our idp picker
         channel = self._make_sso_redirect_request(None)
-        self.assertEqual(channel.code, HTTPStatus.FOUND, channel.result)
+        self.assertEqual(channel.code, 302, channel.result)
         location_headers = channel.headers.getRawHeaders("Location")
         assert location_headers
         uri = location_headers[0]
 
         # hitting that picker should give us some HTML
         channel = self.make_request("GET", uri)
-        self.assertEqual(channel.code, HTTPStatus.OK, channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
 
         # parse the form to check it has fields assumed elsewhere in this class
         html = channel.result["body"].decode("utf-8")
@@ -530,7 +529,7 @@ class MultiSSOTestCase(unittest.HomeserverTestCase):
             + "&idp=cas",
             shorthand=False,
         )
-        self.assertEqual(channel.code, HTTPStatus.FOUND, channel.result)
+        self.assertEqual(channel.code, 302, channel.result)
         location_headers = channel.headers.getRawHeaders("Location")
         assert location_headers
         cas_uri = location_headers[0]
@@ -555,7 +554,7 @@ class MultiSSOTestCase(unittest.HomeserverTestCase):
             + urllib.parse.quote_plus(TEST_CLIENT_REDIRECT_URL)
             + "&idp=saml",
         )
-        self.assertEqual(channel.code, HTTPStatus.FOUND, channel.result)
+        self.assertEqual(channel.code, 302, channel.result)
         location_headers = channel.headers.getRawHeaders("Location")
         assert location_headers
         saml_uri = location_headers[0]
@@ -579,7 +578,7 @@ class MultiSSOTestCase(unittest.HomeserverTestCase):
             + urllib.parse.quote_plus(TEST_CLIENT_REDIRECT_URL)
             + "&idp=oidc",
         )
-        self.assertEqual(channel.code, HTTPStatus.FOUND, channel.result)
+        self.assertEqual(channel.code, 302, channel.result)
         location_headers = channel.headers.getRawHeaders("Location")
         assert location_headers
         oidc_uri = location_headers[0]
@@ -606,7 +605,7 @@ class MultiSSOTestCase(unittest.HomeserverTestCase):
         channel = self.helper.complete_oidc_auth(oidc_uri, cookies, {"sub": "user1"})
 
         # that should serve a confirmation page
-        self.assertEqual(channel.code, HTTPStatus.OK, channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
         content_type_headers = channel.headers.getRawHeaders("Content-Type")
         assert content_type_headers
         self.assertTrue(content_type_headers[-1].startswith("text/html"))
@@ -634,7 +633,7 @@ class MultiSSOTestCase(unittest.HomeserverTestCase):
             "/login",
             content={"type": "m.login.token", "token": login_token},
         )
-        self.assertEqual(chan.code, HTTPStatus.OK, chan.result)
+        self.assertEqual(chan.code, 200, chan.result)
         self.assertEqual(chan.json_body["user_id"], "@user1:test")
 
     def test_multi_sso_redirect_to_unknown(self) -> None:
@@ -643,18 +642,18 @@ class MultiSSOTestCase(unittest.HomeserverTestCase):
             "GET",
             "/_synapse/client/pick_idp?redirectUrl=http://x&idp=xyz",
         )
-        self.assertEqual(channel.code, HTTPStatus.BAD_REQUEST, channel.result)
+        self.assertEqual(channel.code, 400, channel.result)
 
     def test_client_idp_redirect_to_unknown(self) -> None:
         """If the client tries to pick an unknown IdP, return a 404"""
         channel = self._make_sso_redirect_request("xxx")
-        self.assertEqual(channel.code, HTTPStatus.NOT_FOUND, channel.result)
+        self.assertEqual(channel.code, 404, channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_NOT_FOUND")
 
     def test_client_idp_redirect_to_oidc(self) -> None:
         """If the client pick a known IdP, redirect to it"""
         channel = self._make_sso_redirect_request("oidc")
-        self.assertEqual(channel.code, HTTPStatus.FOUND, channel.result)
+        self.assertEqual(channel.code, 302, channel.result)
         location_headers = channel.headers.getRawHeaders("Location")
         assert location_headers
         oidc_uri = location_headers[0]
@@ -765,7 +764,7 @@ class CASTestCase(unittest.HomeserverTestCase):
         channel = self.make_request("GET", cas_ticket_url)
 
         # Test that the response is HTML.
-        self.assertEqual(channel.code, HTTPStatus.OK, channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
         content_type_header_value = ""
         for header in channel.result.get("headers", []):
             if header[0] == b"Content-Type":
@@ -878,17 +877,17 @@ class JWTTestCase(unittest.HomeserverTestCase):
     def test_login_jwt_valid_registered(self) -> None:
         self.register_user("kermit", "monkey")
         channel = self.jwt_login({"sub": "kermit"})
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
         self.assertEqual(channel.json_body["user_id"], "@kermit:test")
 
     def test_login_jwt_valid_unregistered(self) -> None:
         channel = self.jwt_login({"sub": "frog"})
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
         self.assertEqual(channel.json_body["user_id"], "@frog:test")
 
     def test_login_jwt_invalid_signature(self) -> None:
         channel = self.jwt_login({"sub": "frog"}, "notsecret")
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_FORBIDDEN")
         self.assertEqual(
             channel.json_body["error"],
@@ -897,7 +896,7 @@ class JWTTestCase(unittest.HomeserverTestCase):
 
     def test_login_jwt_expired(self) -> None:
         channel = self.jwt_login({"sub": "frog", "exp": 864000})
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_FORBIDDEN")
         self.assertEqual(
             channel.json_body["error"],
@@ -907,7 +906,7 @@ class JWTTestCase(unittest.HomeserverTestCase):
     def test_login_jwt_not_before(self) -> None:
         now = int(time.time())
         channel = self.jwt_login({"sub": "frog", "nbf": now + 3600})
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_FORBIDDEN")
         self.assertEqual(
             channel.json_body["error"],
@@ -916,7 +915,7 @@ class JWTTestCase(unittest.HomeserverTestCase):
 
     def test_login_no_sub(self) -> None:
         channel = self.jwt_login({"username": "root"})
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_FORBIDDEN")
         self.assertEqual(channel.json_body["error"], "Invalid JWT")
 
@@ -925,12 +924,12 @@ class JWTTestCase(unittest.HomeserverTestCase):
         """Test validating the issuer claim."""
         # A valid issuer.
         channel = self.jwt_login({"sub": "kermit", "iss": "test-issuer"})
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
         self.assertEqual(channel.json_body["user_id"], "@kermit:test")
 
         # An invalid issuer.
         channel = self.jwt_login({"sub": "kermit", "iss": "invalid"})
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_FORBIDDEN")
         self.assertEqual(
             channel.json_body["error"],
@@ -939,7 +938,7 @@ class JWTTestCase(unittest.HomeserverTestCase):
 
         # Not providing an issuer.
         channel = self.jwt_login({"sub": "kermit"})
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_FORBIDDEN")
         self.assertEqual(
             channel.json_body["error"],
@@ -949,7 +948,7 @@ class JWTTestCase(unittest.HomeserverTestCase):
     def test_login_iss_no_config(self) -> None:
         """Test providing an issuer claim without requiring it in the configuration."""
         channel = self.jwt_login({"sub": "kermit", "iss": "invalid"})
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
         self.assertEqual(channel.json_body["user_id"], "@kermit:test")
 
     @override_config({"jwt_config": {**base_config, "audiences": ["test-audience"]}})
@@ -957,12 +956,12 @@ class JWTTestCase(unittest.HomeserverTestCase):
         """Test validating the audience claim."""
         # A valid audience.
         channel = self.jwt_login({"sub": "kermit", "aud": "test-audience"})
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
         self.assertEqual(channel.json_body["user_id"], "@kermit:test")
 
         # An invalid audience.
         channel = self.jwt_login({"sub": "kermit", "aud": "invalid"})
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_FORBIDDEN")
         self.assertEqual(
             channel.json_body["error"],
@@ -971,7 +970,7 @@ class JWTTestCase(unittest.HomeserverTestCase):
 
         # Not providing an audience.
         channel = self.jwt_login({"sub": "kermit"})
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_FORBIDDEN")
         self.assertEqual(
             channel.json_body["error"],
@@ -981,7 +980,7 @@ class JWTTestCase(unittest.HomeserverTestCase):
     def test_login_aud_no_config(self) -> None:
         """Test providing an audience without requiring it in the configuration."""
         channel = self.jwt_login({"sub": "kermit", "aud": "invalid"})
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_FORBIDDEN")
         self.assertEqual(
             channel.json_body["error"],
@@ -991,20 +990,20 @@ class JWTTestCase(unittest.HomeserverTestCase):
     def test_login_default_sub(self) -> None:
         """Test reading user ID from the default subject claim."""
         channel = self.jwt_login({"sub": "kermit"})
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
         self.assertEqual(channel.json_body["user_id"], "@kermit:test")
 
     @override_config({"jwt_config": {**base_config, "subject_claim": "username"}})
     def test_login_custom_sub(self) -> None:
         """Test reading user ID from a custom subject claim."""
         channel = self.jwt_login({"username": "frog"})
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
         self.assertEqual(channel.json_body["user_id"], "@frog:test")
 
     def test_login_no_token(self) -> None:
         params = {"type": "org.matrix.login.jwt"}
         channel = self.make_request(b"POST", LOGIN_URL, params)
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_FORBIDDEN")
         self.assertEqual(channel.json_body["error"], "Token field for JWT is missing")
 
@@ -1086,12 +1085,12 @@ class JWTPubKeyTestCase(unittest.HomeserverTestCase):
 
     def test_login_jwt_valid(self) -> None:
         channel = self.jwt_login({"sub": "kermit"})
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
         self.assertEqual(channel.json_body["user_id"], "@kermit:test")
 
     def test_login_jwt_invalid_signature(self) -> None:
         channel = self.jwt_login({"sub": "frog"}, self.bad_privatekey)
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], "M_FORBIDDEN")
         self.assertEqual(
             channel.json_body["error"],
@@ -1152,7 +1151,7 @@ class AppserviceLoginRestServletTestCase(unittest.HomeserverTestCase):
             b"POST", LOGIN_URL, params, access_token=self.service.token
         )
 
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
     def test_login_appservice_user_bot(self) -> None:
         """Test that the appservice bot can use /login"""
@@ -1166,7 +1165,7 @@ class AppserviceLoginRestServletTestCase(unittest.HomeserverTestCase):
             b"POST", LOGIN_URL, params, access_token=self.service.token
         )
 
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
     def test_login_appservice_wrong_user(self) -> None:
         """Test that non-as users cannot login with the as token"""
@@ -1180,7 +1179,7 @@ class AppserviceLoginRestServletTestCase(unittest.HomeserverTestCase):
             b"POST", LOGIN_URL, params, access_token=self.service.token
         )
 
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
 
     def test_login_appservice_wrong_as(self) -> None:
         """Test that as users cannot login with wrong as token"""
@@ -1194,7 +1193,7 @@ class AppserviceLoginRestServletTestCase(unittest.HomeserverTestCase):
             b"POST", LOGIN_URL, params, access_token=self.another_service.token
         )
 
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
 
     def test_login_appservice_no_token(self) -> None:
         """Test that users must provide a token when using the appservice
@@ -1208,7 +1207,7 @@ class AppserviceLoginRestServletTestCase(unittest.HomeserverTestCase):
         }
         channel = self.make_request(b"POST", LOGIN_URL, params)
 
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, msg=channel.result)
 
 
 @skip_unless(HAS_OIDC, "requires OIDC")
@@ -1246,7 +1245,7 @@ class UsernamePickerTestCase(HomeserverTestCase):
         )
 
         # that should redirect to the username picker
-        self.assertEqual(channel.code, HTTPStatus.FOUND, channel.result)
+        self.assertEqual(channel.code, 302, channel.result)
         location_headers = channel.headers.getRawHeaders("Location")
         assert location_headers
         picker_url = location_headers[0]
@@ -1290,7 +1289,7 @@ class UsernamePickerTestCase(HomeserverTestCase):
                 ("Content-Length", str(len(content))),
             ],
         )
-        self.assertEqual(chan.code, HTTPStatus.FOUND, chan.result)
+        self.assertEqual(chan.code, 302, chan.result)
         location_headers = chan.headers.getRawHeaders("Location")
         assert location_headers
 
@@ -1300,7 +1299,7 @@ class UsernamePickerTestCase(HomeserverTestCase):
             path=location_headers[0],
             custom_headers=[("Cookie", "username_mapping_session=" + session_id)],
         )
-        self.assertEqual(chan.code, HTTPStatus.FOUND, chan.result)
+        self.assertEqual(chan.code, 302, chan.result)
         location_headers = chan.headers.getRawHeaders("Location")
         assert location_headers
 
@@ -1325,5 +1324,5 @@ class UsernamePickerTestCase(HomeserverTestCase):
             "/login",
             content={"type": "m.login.token", "token": login_token},
         )
-        self.assertEqual(chan.code, HTTPStatus.OK, chan.result)
+        self.assertEqual(chan.code, 200, chan.result)
         self.assertEqual(chan.json_body["user_id"], "@bobby:test")
diff --git a/tests/rest/client/test_models.py b/tests/rest/client/test_models.py
new file mode 100644
index 0000000000..a9da00665e
--- /dev/null
+++ b/tests/rest/client/test_models.py
@@ -0,0 +1,53 @@
+# Copyright 2022 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import unittest
+
+from pydantic import ValidationError
+
+from synapse.rest.client.models import EmailRequestTokenBody
+
+
+class EmailRequestTokenBodyTestCase(unittest.TestCase):
+    base_request = {
+        "client_secret": "hunter2",
+        "email": "alice@wonderland.com",
+        "send_attempt": 1,
+    }
+
+    def test_token_required_if_id_server_provided(self) -> None:
+        with self.assertRaises(ValidationError):
+            EmailRequestTokenBody.parse_obj(
+                {
+                    **self.base_request,
+                    "id_server": "identity.wonderland.com",
+                }
+            )
+        with self.assertRaises(ValidationError):
+            EmailRequestTokenBody.parse_obj(
+                {
+                    **self.base_request,
+                    "id_server": "identity.wonderland.com",
+                    "id_access_token": None,
+                }
+            )
+
+    def test_token_typechecked_when_id_server_provided(self) -> None:
+        with self.assertRaises(ValidationError):
+            EmailRequestTokenBody.parse_obj(
+                {
+                    **self.base_request,
+                    "id_server": "identity.wonderland.com",
+                    "id_access_token": 1337,
+                }
+            )
diff --git a/tests/rest/client/test_redactions.py b/tests/rest/client/test_redactions.py
index 7401b5e0c0..be4c67d68e 100644
--- a/tests/rest/client/test_redactions.py
+++ b/tests/rest/client/test_redactions.py
@@ -76,12 +76,12 @@ class RedactionsTestCase(HomeserverTestCase):
         path = "/_matrix/client/r0/rooms/%s/redact/%s" % (room_id, event_id)
 
         channel = self.make_request("POST", path, content={}, access_token=access_token)
-        self.assertEqual(int(channel.result["code"]), expect_code)
+        self.assertEqual(channel.code, expect_code)
         return channel.json_body
 
     def _sync_room_timeline(self, access_token: str, room_id: str) -> List[JsonDict]:
         channel = self.make_request("GET", "sync", access_token=self.mod_access_token)
-        self.assertEqual(channel.result["code"], b"200")
+        self.assertEqual(channel.code, 200)
         room_sync = channel.json_body["rooms"]["join"][room_id]
         return room_sync["timeline"]["events"]
 
diff --git a/tests/rest/client/test_register.py b/tests/rest/client/test_register.py
index 071b488cc0..b781875d52 100644
--- a/tests/rest/client/test_register.py
+++ b/tests/rest/client/test_register.py
@@ -70,7 +70,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
             b"POST", self.url + b"?access_token=i_am_an_app_service", request_data
         )
 
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
         det_data = {"user_id": user_id, "home_server": self.hs.hostname}
         self.assertDictContainsSubset(det_data, channel.json_body)
 
@@ -91,7 +91,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
             b"POST", self.url + b"?access_token=i_am_an_app_service", request_data
         )
 
-        self.assertEqual(channel.result["code"], b"400", channel.result)
+        self.assertEqual(channel.code, 400, msg=channel.result)
 
     def test_POST_appservice_registration_invalid(self) -> None:
         self.appservice = None  # no application service exists
@@ -100,20 +100,20 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
             b"POST", self.url + b"?access_token=i_am_an_app_service", request_data
         )
 
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, msg=channel.result)
 
     def test_POST_bad_password(self) -> None:
         request_data = {"username": "kermit", "password": 666}
         channel = self.make_request(b"POST", self.url, request_data)
 
-        self.assertEqual(channel.result["code"], b"400", channel.result)
+        self.assertEqual(channel.code, 400, msg=channel.result)
         self.assertEqual(channel.json_body["error"], "Invalid password")
 
     def test_POST_bad_username(self) -> None:
         request_data = {"username": 777, "password": "monkey"}
         channel = self.make_request(b"POST", self.url, request_data)
 
-        self.assertEqual(channel.result["code"], b"400", channel.result)
+        self.assertEqual(channel.code, 400, msg=channel.result)
         self.assertEqual(channel.json_body["error"], "Invalid username")
 
     def test_POST_user_valid(self) -> None:
@@ -132,7 +132,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
             "home_server": self.hs.hostname,
             "device_id": device_id,
         }
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
         self.assertDictContainsSubset(det_data, channel.json_body)
 
     @override_config({"enable_registration": False})
@@ -142,7 +142,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
 
         channel = self.make_request(b"POST", self.url, request_data)
 
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(channel.json_body["error"], "Registration has been disabled")
         self.assertEqual(channel.json_body["errcode"], "M_FORBIDDEN")
 
@@ -153,7 +153,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
         channel = self.make_request(b"POST", self.url + b"?kind=guest", b"{}")
 
         det_data = {"home_server": self.hs.hostname, "device_id": "guest_device"}
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
         self.assertDictContainsSubset(det_data, channel.json_body)
 
     def test_POST_disabled_guest_registration(self) -> None:
@@ -161,7 +161,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
 
         channel = self.make_request(b"POST", self.url + b"?kind=guest", b"{}")
 
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(channel.json_body["error"], "Guest access is disabled")
 
     @override_config({"rc_registration": {"per_second": 0.17, "burst_count": 5}})
@@ -171,16 +171,16 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
             channel = self.make_request(b"POST", url, b"{}")
 
             if i == 5:
-                self.assertEqual(channel.result["code"], b"429", channel.result)
+                self.assertEqual(channel.code, 429, msg=channel.result)
                 retry_after_ms = int(channel.json_body["retry_after_ms"])
             else:
-                self.assertEqual(channel.result["code"], b"200", channel.result)
+                self.assertEqual(channel.code, 200, msg=channel.result)
 
         self.reactor.advance(retry_after_ms / 1000.0 + 1.0)
 
         channel = self.make_request(b"POST", self.url + b"?kind=guest", b"{}")
 
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
     @override_config({"rc_registration": {"per_second": 0.17, "burst_count": 5}})
     def test_POST_ratelimiting(self) -> None:
@@ -194,16 +194,16 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
             channel = self.make_request(b"POST", self.url, request_data)
 
             if i == 5:
-                self.assertEqual(channel.result["code"], b"429", channel.result)
+                self.assertEqual(channel.code, 429, msg=channel.result)
                 retry_after_ms = int(channel.json_body["retry_after_ms"])
             else:
-                self.assertEqual(channel.result["code"], b"200", channel.result)
+                self.assertEqual(channel.code, 200, msg=channel.result)
 
         self.reactor.advance(retry_after_ms / 1000.0 + 1.0)
 
         channel = self.make_request(b"POST", self.url + b"?kind=guest", b"{}")
 
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
     @override_config({"registration_requires_token": True})
     def test_POST_registration_requires_token(self) -> None:
@@ -231,7 +231,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
 
         # Request without auth to get flows and session
         channel = self.make_request(b"POST", self.url, params)
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, msg=channel.result)
         flows = channel.json_body["flows"]
         # Synapse adds a dummy stage to differentiate flows where otherwise one
         # flow would be a subset of another flow.
@@ -248,7 +248,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
             "session": session,
         }
         channel = self.make_request(b"POST", self.url, params)
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, msg=channel.result)
         completed = channel.json_body["completed"]
         self.assertCountEqual([LoginType.REGISTRATION_TOKEN], completed)
 
@@ -263,7 +263,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
             "home_server": self.hs.hostname,
             "device_id": device_id,
         }
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
         self.assertDictContainsSubset(det_data, channel.json_body)
 
         # Check the `completed` counter has been incremented and pending is 0
@@ -293,21 +293,21 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
             "session": session,
         }
         channel = self.make_request(b"POST", self.url, params)
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], Codes.MISSING_PARAM)
         self.assertEqual(channel.json_body["completed"], [])
 
         # Test with non-string (invalid)
         params["auth"]["token"] = 1234
         channel = self.make_request(b"POST", self.url, params)
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], Codes.INVALID_PARAM)
         self.assertEqual(channel.json_body["completed"], [])
 
         # Test with unknown token (invalid)
         params["auth"]["token"] = "1234"
         channel = self.make_request(b"POST", self.url, params)
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], Codes.UNAUTHORIZED)
         self.assertEqual(channel.json_body["completed"], [])
 
@@ -361,7 +361,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
             "session": session2,
         }
         channel = self.make_request(b"POST", self.url, params2)
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], Codes.UNAUTHORIZED)
         self.assertEqual(channel.json_body["completed"], [])
 
@@ -381,7 +381,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
 
         # Check auth still fails when using token with session2
         channel = self.make_request(b"POST", self.url, params2)
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], Codes.UNAUTHORIZED)
         self.assertEqual(channel.json_body["completed"], [])
 
@@ -415,7 +415,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
             "session": session,
         }
         channel = self.make_request(b"POST", self.url, params)
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, msg=channel.result)
         self.assertEqual(channel.json_body["errcode"], Codes.UNAUTHORIZED)
         self.assertEqual(channel.json_body["completed"], [])
 
@@ -570,7 +570,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
 
     def test_advertised_flows(self) -> None:
         channel = self.make_request(b"POST", self.url, b"{}")
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, msg=channel.result)
         flows = channel.json_body["flows"]
 
         # with the stock config, we only expect the dummy flow
@@ -593,7 +593,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
     )
     def test_advertised_flows_captcha_and_terms_and_3pids(self) -> None:
         channel = self.make_request(b"POST", self.url, b"{}")
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, msg=channel.result)
         flows = channel.json_body["flows"]
 
         self.assertCountEqual(
@@ -625,7 +625,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
     )
     def test_advertised_flows_no_msisdn_email_required(self) -> None:
         channel = self.make_request(b"POST", self.url, b"{}")
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, msg=channel.result)
         flows = channel.json_body["flows"]
 
         # with the stock config, we expect all four combinations of 3pid
@@ -797,13 +797,13 @@ class AccountValidityTestCase(unittest.HomeserverTestCase):
         # endpoint.
         channel = self.make_request(b"GET", "/sync", access_token=tok)
 
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
         self.reactor.advance(datetime.timedelta(weeks=1).total_seconds())
 
         channel = self.make_request(b"GET", "/sync", access_token=tok)
 
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(
             channel.json_body["errcode"], Codes.EXPIRED_ACCOUNT, channel.result
         )
@@ -823,12 +823,12 @@ class AccountValidityTestCase(unittest.HomeserverTestCase):
         url = "/_synapse/admin/v1/account_validity/validity"
         request_data = {"user_id": user_id}
         channel = self.make_request(b"POST", url, request_data, access_token=admin_tok)
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
         # The specific endpoint doesn't matter, all we need is an authenticated
         # endpoint.
         channel = self.make_request(b"GET", "/sync", access_token=tok)
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
     def test_manual_expire(self) -> None:
         user_id = self.register_user("kermit", "monkey")
@@ -844,12 +844,12 @@ class AccountValidityTestCase(unittest.HomeserverTestCase):
             "enable_renewal_emails": False,
         }
         channel = self.make_request(b"POST", url, request_data, access_token=admin_tok)
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
         # The specific endpoint doesn't matter, all we need is an authenticated
         # endpoint.
         channel = self.make_request(b"GET", "/sync", access_token=tok)
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, msg=channel.result)
         self.assertEqual(
             channel.json_body["errcode"], Codes.EXPIRED_ACCOUNT, channel.result
         )
@@ -868,18 +868,18 @@ class AccountValidityTestCase(unittest.HomeserverTestCase):
             "enable_renewal_emails": False,
         }
         channel = self.make_request(b"POST", url, request_data, access_token=admin_tok)
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
         # Try to log the user out
         channel = self.make_request(b"POST", "/logout", access_token=tok)
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
         # Log the user in again (allowed for expired accounts)
         tok = self.login("kermit", "monkey")
 
         # Try to log out all of the user's sessions
         channel = self.make_request(b"POST", "/logout/all", access_token=tok)
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
 
 class AccountValidityRenewalByEmailTestCase(unittest.HomeserverTestCase):
@@ -954,7 +954,7 @@ class AccountValidityRenewalByEmailTestCase(unittest.HomeserverTestCase):
         renewal_token = self.get_success(self.store.get_renewal_token_for_user(user_id))
         url = "/_matrix/client/unstable/account_validity/renew?token=%s" % renewal_token
         channel = self.make_request(b"GET", url)
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
         # Check that we're getting HTML back.
         content_type = channel.headers.getRawHeaders(b"Content-Type")
@@ -972,7 +972,7 @@ class AccountValidityRenewalByEmailTestCase(unittest.HomeserverTestCase):
         # Move 1 day forward. Try to renew with the same token again.
         url = "/_matrix/client/unstable/account_validity/renew?token=%s" % renewal_token
         channel = self.make_request(b"GET", url)
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
         # Check that we're getting HTML back.
         content_type = channel.headers.getRawHeaders(b"Content-Type")
@@ -992,14 +992,14 @@ class AccountValidityRenewalByEmailTestCase(unittest.HomeserverTestCase):
         # succeed.
         self.reactor.advance(datetime.timedelta(days=3).total_seconds())
         channel = self.make_request(b"GET", "/sync", access_token=tok)
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
     def test_renewal_invalid_token(self) -> None:
         # Hit the renewal endpoint with an invalid token and check that it behaves as
         # expected, i.e. that it responds with 404 Not Found and the correct HTML.
         url = "/_matrix/client/unstable/account_validity/renew?token=123"
         channel = self.make_request(b"GET", url)
-        self.assertEqual(channel.result["code"], b"404", channel.result)
+        self.assertEqual(channel.code, 404, msg=channel.result)
 
         # Check that we're getting HTML back.
         content_type = channel.headers.getRawHeaders(b"Content-Type")
@@ -1023,7 +1023,7 @@ class AccountValidityRenewalByEmailTestCase(unittest.HomeserverTestCase):
             "/_matrix/client/unstable/account_validity/send_mail",
             access_token=tok,
         )
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
         self.assertEqual(len(self.email_attempts), 1)
 
@@ -1096,7 +1096,7 @@ class AccountValidityRenewalByEmailTestCase(unittest.HomeserverTestCase):
             "/_matrix/client/unstable/account_validity/send_mail",
             access_token=tok,
         )
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
 
         self.assertEqual(len(self.email_attempts), 1)
 
@@ -1176,7 +1176,7 @@ class RegistrationTokenValidityRestServletTestCase(unittest.HomeserverTestCase):
             b"GET",
             f"{self.url}?token={token}",
         )
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
         self.assertEqual(channel.json_body["valid"], True)
 
     def test_GET_token_invalid(self) -> None:
@@ -1185,7 +1185,7 @@ class RegistrationTokenValidityRestServletTestCase(unittest.HomeserverTestCase):
             b"GET",
             f"{self.url}?token={token}",
         )
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
         self.assertEqual(channel.json_body["valid"], False)
 
     @override_config(
@@ -1201,10 +1201,10 @@ class RegistrationTokenValidityRestServletTestCase(unittest.HomeserverTestCase):
             )
 
             if i == 5:
-                self.assertEqual(channel.result["code"], b"429", channel.result)
+                self.assertEqual(channel.code, 429, msg=channel.result)
                 retry_after_ms = int(channel.json_body["retry_after_ms"])
             else:
-                self.assertEqual(channel.result["code"], b"200", channel.result)
+                self.assertEqual(channel.code, 200, msg=channel.result)
 
         self.reactor.advance(retry_after_ms / 1000.0 + 1.0)
 
@@ -1212,4 +1212,4 @@ class RegistrationTokenValidityRestServletTestCase(unittest.HomeserverTestCase):
             b"GET",
             f"{self.url}?token={token}",
         )
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, msg=channel.result)
diff --git a/tests/rest/client/test_relations.py b/tests/rest/client/test_relations.py
index ad03eee17b..d589f07314 100644
--- a/tests/rest/client/test_relations.py
+++ b/tests/rest/client/test_relations.py
@@ -1060,6 +1060,7 @@ class BundledAggregationsTestCase(BaseRelationsTestCase):
                     participated, bundled_aggregations.get("current_user_participated")
                 )
                 # The latest thread event has some fields that don't matter.
+                self.assertIn("latest_event", bundled_aggregations)
                 self.assert_dict(
                     {
                         "content": {
@@ -1072,7 +1073,7 @@ class BundledAggregationsTestCase(BaseRelationsTestCase):
                         "sender": self.user2_id,
                         "type": "m.room.test",
                     },
-                    bundled_aggregations.get("latest_event"),
+                    bundled_aggregations["latest_event"],
                 )
 
             return assert_thread
@@ -1112,6 +1113,7 @@ class BundledAggregationsTestCase(BaseRelationsTestCase):
             self.assertEqual(2, bundled_aggregations.get("count"))
             self.assertTrue(bundled_aggregations.get("current_user_participated"))
             # The latest thread event has some fields that don't matter.
+            self.assertIn("latest_event", bundled_aggregations)
             self.assert_dict(
                 {
                     "content": {
@@ -1124,7 +1126,7 @@ class BundledAggregationsTestCase(BaseRelationsTestCase):
                     "sender": self.user_id,
                     "type": "m.room.test",
                 },
-                bundled_aggregations.get("latest_event"),
+                bundled_aggregations["latest_event"],
             )
             # Check the unsigned field on the latest event.
             self.assert_dict(
diff --git a/tests/rest/client/test_report_event.py b/tests/rest/client/test_report_event.py
index ad0d0209f7..7cb1017a4a 100644
--- a/tests/rest/client/test_report_event.py
+++ b/tests/rest/client/test_report_event.py
@@ -77,6 +77,4 @@ class ReportEventTestCase(unittest.HomeserverTestCase):
         channel = self.make_request(
             "POST", self.report_path, data, access_token=self.other_user_tok
         )
-        self.assertEqual(
-            response_status, int(channel.result["code"]), msg=channel.result["body"]
-        )
+        self.assertEqual(response_status, channel.code, msg=channel.result["body"])
diff --git a/tests/rest/client/test_retention.py b/tests/rest/client/test_retention.py
index ac9c113354..9c8c1889d3 100644
--- a/tests/rest/client/test_retention.py
+++ b/tests/rest/client/test_retention.py
@@ -20,7 +20,7 @@ from synapse.api.constants import EventTypes
 from synapse.rest import admin
 from synapse.rest.client import login, room
 from synapse.server import HomeServer
-from synapse.types import JsonDict
+from synapse.types import JsonDict, create_requester
 from synapse.util import Clock
 from synapse.visibility import filter_events_for_client
 
@@ -188,7 +188,7 @@ class RetentionTestCase(unittest.HomeserverTestCase):
         message_handler = self.hs.get_message_handler()
         create_event = self.get_success(
             message_handler.get_room_data(
-                self.user_id, room_id, EventTypes.Create, state_key=""
+                create_requester(self.user_id), room_id, EventTypes.Create, state_key=""
             )
         )
 
diff --git a/tests/rest/client/test_rooms.py b/tests/rest/client/test_rooms.py
index c45cb32090..aa2f578441 100644
--- a/tests/rest/client/test_rooms.py
+++ b/tests/rest/client/test_rooms.py
@@ -496,7 +496,7 @@ class RoomStateTestCase(RoomBase):
 
         self.assertEqual(HTTPStatus.OK, channel.code, msg=channel.result["body"])
         self.assertCountEqual(
-            [state_event["type"] for state_event in channel.json_body],
+            [state_event["type"] for state_event in channel.json_list],
             {
                 "m.room.create",
                 "m.room.power_levels",
@@ -2070,7 +2070,6 @@ class PublicRoomsRoomTypeFilterTestCase(unittest.HomeserverTestCase):
 
         config = self.default_config()
         config["allow_public_rooms_without_auth"] = True
-        config["experimental_features"] = {"msc3827_enabled": True}
         self.hs = self.setup_test_homeserver(config=config)
         self.url = b"/_matrix/client/r0/publicRooms"
 
@@ -2123,13 +2122,13 @@ class PublicRoomsRoomTypeFilterTestCase(unittest.HomeserverTestCase):
         chunk, count = self.make_public_rooms_request([None])
 
         self.assertEqual(count, 1)
-        self.assertEqual(chunk[0].get("org.matrix.msc3827.room_type", None), None)
+        self.assertEqual(chunk[0].get("room_type", None), None)
 
     def test_returns_only_space_based_on_filter(self) -> None:
         chunk, count = self.make_public_rooms_request(["m.space"])
 
         self.assertEqual(count, 1)
-        self.assertEqual(chunk[0].get("org.matrix.msc3827.room_type", None), "m.space")
+        self.assertEqual(chunk[0].get("room_type", None), "m.space")
 
     def test_returns_both_rooms_and_space_based_on_filter(self) -> None:
         chunk, count = self.make_public_rooms_request(["m.space", None])
diff --git a/tests/rest/client/test_shadow_banned.py b/tests/rest/client/test_shadow_banned.py
index d9bd8c4a28..c50f034b34 100644
--- a/tests/rest/client/test_shadow_banned.py
+++ b/tests/rest/client/test_shadow_banned.py
@@ -26,7 +26,7 @@ from synapse.rest.client import (
     room_upgrade_rest_servlet,
 )
 from synapse.server import HomeServer
-from synapse.types import UserID
+from synapse.types import UserID, create_requester
 from synapse.util import Clock
 
 from tests import unittest
@@ -275,7 +275,7 @@ class ProfileTestCase(_ShadowBannedBase):
         message_handler = self.hs.get_message_handler()
         event = self.get_success(
             message_handler.get_room_data(
-                self.banned_user_id,
+                create_requester(self.banned_user_id),
                 room_id,
                 "m.room.member",
                 self.banned_user_id,
@@ -310,7 +310,7 @@ class ProfileTestCase(_ShadowBannedBase):
         message_handler = self.hs.get_message_handler()
         event = self.get_success(
             message_handler.get_room_data(
-                self.banned_user_id,
+                create_requester(self.banned_user_id),
                 room_id,
                 "m.room.member",
                 self.banned_user_id,
diff --git a/tests/rest/client/test_sync.py b/tests/rest/client/test_sync.py
index b085c50356..de0dec8539 100644
--- a/tests/rest/client/test_sync.py
+++ b/tests/rest/client/test_sync.py
@@ -38,7 +38,6 @@ from tests.federation.transport.test_knocking import (
     KnockingStrippedStateEventHelperMixin,
 )
 from tests.server import TimedOutException
-from tests.unittest import override_config
 
 
 class FilterTestCase(unittest.HomeserverTestCase):
@@ -390,6 +389,12 @@ class ReadReceiptsTestCase(unittest.HomeserverTestCase):
         sync.register_servlets,
     ]
 
+    def make_homeserver(self, reactor: MemoryReactor, clock: Clock) -> HomeServer:
+        config = self.default_config()
+        config["experimental_features"] = {"msc2285_enabled": True}
+
+        return self.setup_test_homeserver(config=config)
+
     def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.url = "/sync?since=%s"
         self.next_batch = "s0"
@@ -408,15 +413,17 @@ class ReadReceiptsTestCase(unittest.HomeserverTestCase):
         # Join the second user
         self.helper.join(room=self.room_id, user=self.user2, tok=self.tok2)
 
-    @override_config({"experimental_features": {"msc2285_enabled": True}})
-    def test_private_read_receipts(self) -> None:
+    @parameterized.expand(
+        [ReceiptTypes.READ_PRIVATE, ReceiptTypes.UNSTABLE_READ_PRIVATE]
+    )
+    def test_private_read_receipts(self, receipt_type: str) -> None:
         # Send a message as the first user
         res = self.helper.send(self.room_id, body="hello", tok=self.tok)
 
         # Send a private read receipt to tell the server the first user's message was read
         channel = self.make_request(
             "POST",
-            f"/rooms/{self.room_id}/receipt/org.matrix.msc2285.read.private/{res['event_id']}",
+            f"/rooms/{self.room_id}/receipt/{receipt_type}/{res['event_id']}",
             {},
             access_token=self.tok2,
         )
@@ -425,8 +432,10 @@ class ReadReceiptsTestCase(unittest.HomeserverTestCase):
         # Test that the first user can't see the other user's private read receipt
         self.assertIsNone(self._get_read_receipt())
 
-    @override_config({"experimental_features": {"msc2285_enabled": True}})
-    def test_public_receipt_can_override_private(self) -> None:
+    @parameterized.expand(
+        [ReceiptTypes.READ_PRIVATE, ReceiptTypes.UNSTABLE_READ_PRIVATE]
+    )
+    def test_public_receipt_can_override_private(self, receipt_type: str) -> None:
         """
         Sending a public read receipt to the same event which has a private read
         receipt should cause that receipt to become public.
@@ -437,7 +446,7 @@ class ReadReceiptsTestCase(unittest.HomeserverTestCase):
         # Send a private read receipt
         channel = self.make_request(
             "POST",
-            f"/rooms/{self.room_id}/receipt/{ReceiptTypes.READ_PRIVATE}/{res['event_id']}",
+            f"/rooms/{self.room_id}/receipt/{receipt_type}/{res['event_id']}",
             {},
             access_token=self.tok2,
         )
@@ -456,8 +465,10 @@ class ReadReceiptsTestCase(unittest.HomeserverTestCase):
         # Test that we did override the private read receipt
         self.assertNotEqual(self._get_read_receipt(), None)
 
-    @override_config({"experimental_features": {"msc2285_enabled": True}})
-    def test_private_receipt_cannot_override_public(self) -> None:
+    @parameterized.expand(
+        [ReceiptTypes.READ_PRIVATE, ReceiptTypes.UNSTABLE_READ_PRIVATE]
+    )
+    def test_private_receipt_cannot_override_public(self, receipt_type: str) -> None:
         """
         Sending a private read receipt to the same event which has a public read
         receipt should cause no change.
@@ -478,7 +489,7 @@ class ReadReceiptsTestCase(unittest.HomeserverTestCase):
         # Send a private read receipt
         channel = self.make_request(
             "POST",
-            f"/rooms/{self.room_id}/receipt/{ReceiptTypes.READ_PRIVATE}/{res['event_id']}",
+            f"/rooms/{self.room_id}/receipt/{receipt_type}/{res['event_id']}",
             {},
             access_token=self.tok2,
         )
@@ -590,7 +601,10 @@ class UnreadMessagesTestCase(unittest.HomeserverTestCase):
             tok=self.tok,
         )
 
-    def test_unread_counts(self) -> None:
+    @parameterized.expand(
+        [ReceiptTypes.READ_PRIVATE, ReceiptTypes.UNSTABLE_READ_PRIVATE]
+    )
+    def test_unread_counts(self, receipt_type: str) -> None:
         """Tests that /sync returns the right value for the unread count (MSC2654)."""
 
         # Check that our own messages don't increase the unread count.
@@ -624,7 +638,7 @@ class UnreadMessagesTestCase(unittest.HomeserverTestCase):
         # Send a read receipt to tell the server we've read the latest event.
         channel = self.make_request(
             "POST",
-            f"/rooms/{self.room_id}/receipt/org.matrix.msc2285.read.private/{res['event_id']}",
+            f"/rooms/{self.room_id}/receipt/{receipt_type}/{res['event_id']}",
             {},
             access_token=self.tok,
         )
@@ -700,7 +714,7 @@ class UnreadMessagesTestCase(unittest.HomeserverTestCase):
         self._check_unread_count(5)
         res2 = self.helper.send(self.room_id, "hello", tok=self.tok2)
 
-        # Make sure both m.read and org.matrix.msc2285.read.private advance
+        # Make sure both m.read and m.read.private advance
         channel = self.make_request(
             "POST",
             f"/rooms/{self.room_id}/receipt/m.read/{res1['event_id']}",
@@ -712,16 +726,22 @@ class UnreadMessagesTestCase(unittest.HomeserverTestCase):
 
         channel = self.make_request(
             "POST",
-            f"/rooms/{self.room_id}/receipt/org.matrix.msc2285.read.private/{res2['event_id']}",
+            f"/rooms/{self.room_id}/receipt/{receipt_type}/{res2['event_id']}",
             {},
             access_token=self.tok,
         )
         self.assertEqual(channel.code, 200, channel.json_body)
         self._check_unread_count(0)
 
-    # We test for both receipt types that influence notification counts
-    @parameterized.expand([ReceiptTypes.READ, ReceiptTypes.READ_PRIVATE])
-    def test_read_receipts_only_go_down(self, receipt_type: ReceiptTypes) -> None:
+    # We test for all three receipt types that influence notification counts
+    @parameterized.expand(
+        [
+            ReceiptTypes.READ,
+            ReceiptTypes.READ_PRIVATE,
+            ReceiptTypes.UNSTABLE_READ_PRIVATE,
+        ]
+    )
+    def test_read_receipts_only_go_down(self, receipt_type: str) -> None:
         # Join the new user
         self.helper.join(room=self.room_id, user=self.user2, tok=self.tok2)
 
@@ -739,11 +759,11 @@ class UnreadMessagesTestCase(unittest.HomeserverTestCase):
         self.assertEqual(channel.code, 200, channel.json_body)
         self._check_unread_count(0)
 
-        # Make sure neither m.read nor org.matrix.msc2285.read.private make the
+        # Make sure neither m.read nor m.read.private make the
         # read receipt go up to an older event
         channel = self.make_request(
             "POST",
-            f"/rooms/{self.room_id}/receipt/org.matrix.msc2285.read.private/{res1['event_id']}",
+            f"/rooms/{self.room_id}/receipt/{receipt_type}/{res1['event_id']}",
             {},
             access_token=self.tok,
         )
@@ -948,3 +968,24 @@ class ExcludeRoomTestCase(unittest.HomeserverTestCase):
 
         self.assertNotIn(self.excluded_room_id, channel.json_body["rooms"]["invite"])
         self.assertIn(self.included_room_id, channel.json_body["rooms"]["invite"])
+
+    def test_incremental_sync(self) -> None:
+        """Tests that activity in the room is properly filtered out of incremental
+        syncs.
+        """
+        channel = self.make_request("GET", "/sync", access_token=self.tok)
+        self.assertEqual(channel.code, 200, channel.result)
+        next_batch = channel.json_body["next_batch"]
+
+        self.helper.send(self.excluded_room_id, tok=self.tok)
+        self.helper.send(self.included_room_id, tok=self.tok)
+
+        channel = self.make_request(
+            "GET",
+            f"/sync?since={next_batch}",
+            access_token=self.tok,
+        )
+        self.assertEqual(channel.code, 200, channel.result)
+
+        self.assertNotIn(self.excluded_room_id, channel.json_body["rooms"]["join"])
+        self.assertIn(self.included_room_id, channel.json_body["rooms"]["join"])
diff --git a/tests/rest/client/test_third_party_rules.py b/tests/rest/client/test_third_party_rules.py
index 9a48e9286f..3325d43a2f 100644
--- a/tests/rest/client/test_third_party_rules.py
+++ b/tests/rest/client/test_third_party_rules.py
@@ -20,6 +20,7 @@ from twisted.test.proto_helpers import MemoryReactor
 from synapse.api.constants import EventTypes, LoginType, Membership
 from synapse.api.errors import SynapseError
 from synapse.api.room_versions import RoomVersion
+from synapse.config.homeserver import HomeServerConfig
 from synapse.events import EventBase
 from synapse.events.third_party_rules import load_legacy_third_party_event_rules
 from synapse.rest import admin
@@ -154,7 +155,7 @@ class ThirdPartyRulesTestCase(unittest.FederatingHomeserverTestCase):
             {},
             access_token=self.tok,
         )
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
 
         callback.assert_called_once()
 
@@ -172,7 +173,7 @@ class ThirdPartyRulesTestCase(unittest.FederatingHomeserverTestCase):
             {},
             access_token=self.tok,
         )
-        self.assertEqual(channel.result["code"], b"403", channel.result)
+        self.assertEqual(channel.code, 403, channel.result)
 
     def test_third_party_rules_workaround_synapse_errors_pass_through(self) -> None:
         """
@@ -185,12 +186,12 @@ class ThirdPartyRulesTestCase(unittest.FederatingHomeserverTestCase):
         """
 
         class NastyHackException(SynapseError):
-            def error_dict(self) -> JsonDict:
+            def error_dict(self, config: Optional[HomeServerConfig]) -> JsonDict:
                 """
                 This overrides SynapseError's `error_dict` to nastily inject
                 JSON into the error response.
                 """
-                result = super().error_dict()
+                result = super().error_dict(config)
                 result["nasty"] = "very"
                 return result
 
@@ -210,7 +211,7 @@ class ThirdPartyRulesTestCase(unittest.FederatingHomeserverTestCase):
             access_token=self.tok,
         )
         # Check the error code
-        self.assertEqual(channel.result["code"], b"429", channel.result)
+        self.assertEqual(channel.code, 429, channel.result)
         # Check the JSON body has had the `nasty` key injected
         self.assertEqual(
             channel.json_body,
@@ -259,7 +260,7 @@ class ThirdPartyRulesTestCase(unittest.FederatingHomeserverTestCase):
             {"x": "x"},
             access_token=self.tok,
         )
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
         event_id = channel.json_body["event_id"]
 
         # ... and check that it got modified
@@ -268,7 +269,7 @@ class ThirdPartyRulesTestCase(unittest.FederatingHomeserverTestCase):
             "/_matrix/client/r0/rooms/%s/event/%s" % (self.room_id, event_id),
             access_token=self.tok,
         )
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
         ev = channel.json_body
         self.assertEqual(ev["content"]["x"], "y")
 
@@ -297,7 +298,7 @@ class ThirdPartyRulesTestCase(unittest.FederatingHomeserverTestCase):
             },
             access_token=self.tok,
         )
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
         orig_event_id = channel.json_body["event_id"]
 
         channel = self.make_request(
@@ -314,7 +315,7 @@ class ThirdPartyRulesTestCase(unittest.FederatingHomeserverTestCase):
             },
             access_token=self.tok,
         )
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
         edited_event_id = channel.json_body["event_id"]
 
         # ... and check that they both got modified
@@ -323,7 +324,7 @@ class ThirdPartyRulesTestCase(unittest.FederatingHomeserverTestCase):
             "/_matrix/client/r0/rooms/%s/event/%s" % (self.room_id, orig_event_id),
             access_token=self.tok,
         )
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
         ev = channel.json_body
         self.assertEqual(ev["content"]["body"], "ORIGINAL BODY")
 
@@ -332,7 +333,7 @@ class ThirdPartyRulesTestCase(unittest.FederatingHomeserverTestCase):
             "/_matrix/client/r0/rooms/%s/event/%s" % (self.room_id, edited_event_id),
             access_token=self.tok,
         )
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
         ev = channel.json_body
         self.assertEqual(ev["content"]["body"], "EDITED BODY")
 
@@ -378,7 +379,7 @@ class ThirdPartyRulesTestCase(unittest.FederatingHomeserverTestCase):
             },
             access_token=self.tok,
         )
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
 
         event_id = channel.json_body["event_id"]
 
@@ -387,7 +388,7 @@ class ThirdPartyRulesTestCase(unittest.FederatingHomeserverTestCase):
             "/_matrix/client/r0/rooms/%s/event/%s" % (self.room_id, event_id),
             access_token=self.tok,
         )
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
 
         self.assertIn("foo", channel.json_body["content"].keys())
         self.assertEqual(channel.json_body["content"]["foo"], "bar")
diff --git a/tests/rest/client/utils.py b/tests/rest/client/utils.py
index 105d418698..dd26145bf8 100644
--- a/tests/rest/client/utils.py
+++ b/tests/rest/client/utils.py
@@ -140,7 +140,7 @@ class RestHelper:
             custom_headers=custom_headers,
         )
 
-        assert channel.result["code"] == b"%d" % expect_code, channel.result
+        assert channel.code == expect_code, channel.result
         self.auth_user_id = temp_id
 
         if expect_code == HTTPStatus.OK:
@@ -213,11 +213,9 @@ class RestHelper:
             data,
         )
 
-        assert (
-            int(channel.result["code"]) == expect_code
-        ), "Expected: %d, got: %d, resp: %r" % (
+        assert channel.code == expect_code, "Expected: %d, got: %d, resp: %r" % (
             expect_code,
-            int(channel.result["code"]),
+            channel.code,
             channel.result["body"],
         )
 
@@ -312,11 +310,9 @@ class RestHelper:
             data,
         )
 
-        assert (
-            int(channel.result["code"]) == expect_code
-        ), "Expected: %d, got: %d, resp: %r" % (
+        assert channel.code == expect_code, "Expected: %d, got: %d, resp: %r" % (
             expect_code,
-            int(channel.result["code"]),
+            channel.code,
             channel.result["body"],
         )
 
@@ -396,11 +392,9 @@ class RestHelper:
             custom_headers=custom_headers,
         )
 
-        assert (
-            int(channel.result["code"]) == expect_code
-        ), "Expected: %d, got: %d, resp: %r" % (
+        assert channel.code == expect_code, "Expected: %d, got: %d, resp: %r" % (
             expect_code,
-            int(channel.result["code"]),
+            channel.code,
             channel.result["body"],
         )
 
@@ -449,11 +443,9 @@ class RestHelper:
 
         channel = make_request(self.hs.get_reactor(), self.site, method, path, content)
 
-        assert (
-            int(channel.result["code"]) == expect_code
-        ), "Expected: %d, got: %d, resp: %r" % (
+        assert channel.code == expect_code, "Expected: %d, got: %d, resp: %r" % (
             expect_code,
-            int(channel.result["code"]),
+            channel.code,
             channel.result["body"],
         )
 
@@ -545,7 +537,7 @@ class RestHelper:
 
         assert channel.code == expect_code, "Expected: %d, got: %d, resp: %r" % (
             expect_code,
-            int(channel.result["code"]),
+            channel.code,
             channel.result["body"],
         )
 
diff --git a/tests/rest/test_health.py b/tests/rest/test_health.py
index da325955f8..c0a2501742 100644
--- a/tests/rest/test_health.py
+++ b/tests/rest/test_health.py
@@ -11,8 +11,6 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from http import HTTPStatus
-
 from synapse.rest.health import HealthResource
 
 from tests import unittest
@@ -26,5 +24,5 @@ class HealthCheckTests(unittest.HomeserverTestCase):
     def test_health(self) -> None:
         channel = self.make_request("GET", "/health", shorthand=False)
 
-        self.assertEqual(channel.code, HTTPStatus.OK)
+        self.assertEqual(channel.code, 200)
         self.assertEqual(channel.result["body"], b"OK")
diff --git a/tests/rest/test_well_known.py b/tests/rest/test_well_known.py
index d8faafec75..2091b08d89 100644
--- a/tests/rest/test_well_known.py
+++ b/tests/rest/test_well_known.py
@@ -11,8 +11,6 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from http import HTTPStatus
-
 from twisted.web.resource import Resource
 
 from synapse.rest.well_known import well_known_resource
@@ -38,7 +36,7 @@ class WellKnownTests(unittest.HomeserverTestCase):
             "GET", "/.well-known/matrix/client", shorthand=False
         )
 
-        self.assertEqual(channel.code, HTTPStatus.OK)
+        self.assertEqual(channel.code, 200)
         self.assertEqual(
             channel.json_body,
             {
@@ -57,7 +55,7 @@ class WellKnownTests(unittest.HomeserverTestCase):
             "GET", "/.well-known/matrix/client", shorthand=False
         )
 
-        self.assertEqual(channel.code, HTTPStatus.NOT_FOUND)
+        self.assertEqual(channel.code, 404)
 
     @unittest.override_config(
         {
@@ -71,7 +69,7 @@ class WellKnownTests(unittest.HomeserverTestCase):
             "GET", "/.well-known/matrix/client", shorthand=False
         )
 
-        self.assertEqual(channel.code, HTTPStatus.OK)
+        self.assertEqual(channel.code, 200)
         self.assertEqual(
             channel.json_body,
             {
@@ -87,7 +85,7 @@ class WellKnownTests(unittest.HomeserverTestCase):
             "GET", "/.well-known/matrix/server", shorthand=False
         )
 
-        self.assertEqual(channel.code, HTTPStatus.OK)
+        self.assertEqual(channel.code, 200)
         self.assertEqual(
             channel.json_body,
             {"m.server": "test:443"},
@@ -97,4 +95,4 @@ class WellKnownTests(unittest.HomeserverTestCase):
         channel = self.make_request(
             "GET", "/.well-known/matrix/server", shorthand=False
         )
-        self.assertEqual(channel.code, HTTPStatus.NOT_FOUND)
+        self.assertEqual(channel.code, 404)
diff --git a/tests/server.py b/tests/server.py
index df3f1564c9..c447d5e4c4 100644
--- a/tests/server.py
+++ b/tests/server.py
@@ -25,6 +25,7 @@ from typing import (
     Callable,
     Dict,
     Iterable,
+    List,
     MutableMapping,
     Optional,
     Tuple,
@@ -60,6 +61,10 @@ from twisted.web.resource import IResource
 from twisted.web.server import Request, Site
 
 from synapse.config.database import DatabaseConnectionConfig
+from synapse.events.presence_router import load_legacy_presence_router
+from synapse.events.spamcheck import load_legacy_spam_checkers
+from synapse.events.third_party_rules import load_legacy_third_party_event_rules
+from synapse.handlers.auth import load_legacy_password_auth_providers
 from synapse.http.site import SynapseRequest
 from synapse.logging.context import ContextResourceUsage
 from synapse.server import HomeServer
@@ -121,7 +126,15 @@ class FakeChannel:
 
     @property
     def json_body(self) -> JsonDict:
-        return json.loads(self.text_body)
+        body = json.loads(self.text_body)
+        assert isinstance(body, dict)
+        return body
+
+    @property
+    def json_list(self) -> List[JsonDict]:
+        body = json.loads(self.text_body)
+        assert isinstance(body, list)
+        return body
 
     @property
     def text_body(self) -> str:
@@ -904,4 +917,14 @@ def setup_test_homeserver(
     # Make the threadpool and database transactions synchronous for testing.
     _make_test_homeserver_synchronous(hs)
 
+    # Load any configured modules into the homeserver
+    module_api = hs.get_module_api()
+    for module, config in hs.config.modules.loaded_modules:
+        module(config=config, api=module_api)
+
+    load_legacy_spam_checkers(hs)
+    load_legacy_third_party_event_rules(hs)
+    load_legacy_presence_router(hs)
+    load_legacy_password_auth_providers(hs)
+
     return hs
diff --git a/tests/server_notices/test_resource_limits_server_notices.py b/tests/server_notices/test_resource_limits_server_notices.py
index e07ae78fc4..bf403045e9 100644
--- a/tests/server_notices/test_resource_limits_server_notices.py
+++ b/tests/server_notices/test_resource_limits_server_notices.py
@@ -11,16 +11,19 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-
 from unittest.mock import Mock
 
+from twisted.test.proto_helpers import MemoryReactor
+
 from synapse.api.constants import EventTypes, LimitBlockingTypes, ServerNoticeMsgType
 from synapse.api.errors import ResourceLimitError
 from synapse.rest import admin
 from synapse.rest.client import login, room, sync
+from synapse.server import HomeServer
 from synapse.server_notices.resource_limits_server_notices import (
     ResourceLimitsServerNotices,
 )
+from synapse.util import Clock
 
 from tests import unittest
 from tests.test_utils import make_awaitable
@@ -52,7 +55,7 @@ class TestResourceLimitsServerNotices(unittest.HomeserverTestCase):
 
         return config
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.server_notices_sender = self.hs.get_server_notices_sender()
 
         # relying on [1] is far from ideal, but the only case where
@@ -251,7 +254,7 @@ class TestResourceLimitsServerNoticesWithRealRooms(unittest.HomeserverTestCase):
         c["admin_contact"] = "mailto:user@test.com"
         return c
 
-    def prepare(self, reactor, clock, hs):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         self.store = self.hs.get_datastores().main
         self.server_notices_sender = self.hs.get_server_notices_sender()
         self.server_notices_manager = self.hs.get_server_notices_manager()
diff --git a/tests/storage/test_event_push_actions.py b/tests/storage/test_event_push_actions.py
index ba40124c8a..62fd4aeb2f 100644
--- a/tests/storage/test_event_push_actions.py
+++ b/tests/storage/test_event_push_actions.py
@@ -135,7 +135,22 @@ class EventPushActionsStoreTestCase(HomeserverTestCase):
         _assert_counts(1, 1, 0)
 
         # Delete old event push actions, this should not affect the (summarised) count.
+        #
+        # All event push actions are kept for 24 hours, so need to move forward
+        # in time.
+        self.pump(60 * 60 * 24)
         self.get_success(self.store._remove_old_push_actions_that_have_rotated())
+        # Double check that the event push actions have been cleared (i.e. that
+        # any results *must* come from the summary).
+        result = self.get_success(
+            self.store.db_pool.simple_select_list(
+                table="event_push_actions",
+                keyvalues={"1": 1},
+                retcols=("event_id",),
+                desc="",
+            )
+        )
+        self.assertEqual(result, [])
         _assert_counts(1, 1, 0)
 
         _mark_read(last_event_id)
diff --git a/tests/storage/test_events.py b/tests/storage/test_events.py
index 2ff88e64a5..3ce4f35cb7 100644
--- a/tests/storage/test_events.py
+++ b/tests/storage/test_events.py
@@ -70,7 +70,11 @@ class ExtremPruneTestCase(HomeserverTestCase):
     def persist_event(self, event, state=None):
         """Persist the event, with optional state"""
         context = self.get_success(
-            self.state.compute_event_context(event, state_ids_before_event=state)
+            self.state.compute_event_context(
+                event,
+                state_ids_before_event=state,
+                partial_state=None if state is None else False,
+            )
         )
         self.get_success(self._persistence.persist_event(event, context))
 
@@ -148,6 +152,7 @@ class ExtremPruneTestCase(HomeserverTestCase):
             self.state.compute_event_context(
                 remote_event_2,
                 state_ids_before_event=state_before_gap,
+                partial_state=False,
             )
         )
 
diff --git a/tests/replication/slave/storage/test_receipts.py b/tests/storage/test_receipts.py
index 19f57115a1..191c957fb5 100644
--- a/tests/replication/slave/storage/test_receipts.py
+++ b/tests/storage/test_receipts.py
@@ -12,24 +12,24 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from parameterized import parameterized
+
 from synapse.api.constants import ReceiptTypes
-from synapse.replication.slave.storage.receipts import SlavedReceiptsStore
 from synapse.types import UserID, create_requester
 
 from tests.test_utils.event_injection import create_event
-
-from ._base import BaseSlavedStoreTestCase
+from tests.unittest import HomeserverTestCase
 
 OTHER_USER_ID = "@other:test"
 OUR_USER_ID = "@our:test"
 
 
-class SlavedReceiptTestCase(BaseSlavedStoreTestCase):
+class ReceiptTestCase(HomeserverTestCase):
+    def prepare(self, reactor, clock, homeserver) -> None:
+        super().prepare(reactor, clock, homeserver)
 
-    STORE_TYPE = SlavedReceiptsStore
+        self.store = homeserver.get_datastores().main
 
-    def prepare(self, reactor, clock, homeserver):
-        super().prepare(reactor, clock, homeserver)
         self.room_creator = homeserver.get_room_creation_handler()
         self.persist_event_storage_controller = (
             self.hs.get_storage_controllers().persistence
@@ -85,32 +85,48 @@ class SlavedReceiptTestCase(BaseSlavedStoreTestCase):
             )
         )
 
-    def test_return_empty_with_no_data(self):
+    def test_return_empty_with_no_data(self) -> None:
         res = self.get_success(
-            self.master_store.get_receipts_for_user(
-                OUR_USER_ID, [ReceiptTypes.READ, ReceiptTypes.READ_PRIVATE]
+            self.store.get_receipts_for_user(
+                OUR_USER_ID,
+                [
+                    ReceiptTypes.READ,
+                    ReceiptTypes.READ_PRIVATE,
+                    ReceiptTypes.UNSTABLE_READ_PRIVATE,
+                ],
             )
         )
         self.assertEqual(res, {})
 
         res = self.get_success(
-            self.master_store.get_receipts_for_user_with_orderings(
+            self.store.get_receipts_for_user_with_orderings(
                 OUR_USER_ID,
-                [ReceiptTypes.READ, ReceiptTypes.READ_PRIVATE],
+                [
+                    ReceiptTypes.READ,
+                    ReceiptTypes.READ_PRIVATE,
+                    ReceiptTypes.UNSTABLE_READ_PRIVATE,
+                ],
             )
         )
         self.assertEqual(res, {})
 
         res = self.get_success(
-            self.master_store.get_last_receipt_event_id_for_user(
+            self.store.get_last_receipt_event_id_for_user(
                 OUR_USER_ID,
                 self.room_id1,
-                [ReceiptTypes.READ, ReceiptTypes.READ_PRIVATE],
+                [
+                    ReceiptTypes.READ,
+                    ReceiptTypes.READ_PRIVATE,
+                    ReceiptTypes.UNSTABLE_READ_PRIVATE,
+                ],
             )
         )
         self.assertEqual(res, None)
 
-    def test_get_receipts_for_user(self):
+    @parameterized.expand(
+        [ReceiptTypes.READ_PRIVATE, ReceiptTypes.UNSTABLE_READ_PRIVATE]
+    )
+    def test_get_receipts_for_user(self, receipt_type: str) -> None:
         # Send some events into the first room
         event1_1_id = self.create_and_send_event(
             self.room_id1, UserID.from_string(OTHER_USER_ID)
@@ -121,47 +137,45 @@ class SlavedReceiptTestCase(BaseSlavedStoreTestCase):
 
         # Send public read receipt for the first event
         self.get_success(
-            self.master_store.insert_receipt(
+            self.store.insert_receipt(
                 self.room_id1, ReceiptTypes.READ, OUR_USER_ID, [event1_1_id], {}
             )
         )
         # Send private read receipt for the second event
         self.get_success(
-            self.master_store.insert_receipt(
-                self.room_id1, ReceiptTypes.READ_PRIVATE, OUR_USER_ID, [event1_2_id], {}
+            self.store.insert_receipt(
+                self.room_id1, receipt_type, OUR_USER_ID, [event1_2_id], {}
             )
         )
 
         # Test we get the latest event when we want both private and public receipts
         res = self.get_success(
-            self.master_store.get_receipts_for_user(
-                OUR_USER_ID, [ReceiptTypes.READ, ReceiptTypes.READ_PRIVATE]
+            self.store.get_receipts_for_user(
+                OUR_USER_ID, [ReceiptTypes.READ, receipt_type]
             )
         )
         self.assertEqual(res, {self.room_id1: event1_2_id})
 
         # Test we get the older event when we want only public receipt
         res = self.get_success(
-            self.master_store.get_receipts_for_user(OUR_USER_ID, [ReceiptTypes.READ])
+            self.store.get_receipts_for_user(OUR_USER_ID, [ReceiptTypes.READ])
         )
         self.assertEqual(res, {self.room_id1: event1_1_id})
 
         # Test we get the latest event when we want only the public receipt
         res = self.get_success(
-            self.master_store.get_receipts_for_user(
-                OUR_USER_ID, [ReceiptTypes.READ_PRIVATE]
-            )
+            self.store.get_receipts_for_user(OUR_USER_ID, [receipt_type])
         )
         self.assertEqual(res, {self.room_id1: event1_2_id})
 
         # Test receipt updating
         self.get_success(
-            self.master_store.insert_receipt(
+            self.store.insert_receipt(
                 self.room_id1, ReceiptTypes.READ, OUR_USER_ID, [event1_2_id], {}
             )
         )
         res = self.get_success(
-            self.master_store.get_receipts_for_user(OUR_USER_ID, [ReceiptTypes.READ])
+            self.store.get_receipts_for_user(OUR_USER_ID, [ReceiptTypes.READ])
         )
         self.assertEqual(res, {self.room_id1: event1_2_id})
 
@@ -172,18 +186,21 @@ class SlavedReceiptTestCase(BaseSlavedStoreTestCase):
 
         # Test new room is reflected in what the method returns
         self.get_success(
-            self.master_store.insert_receipt(
-                self.room_id2, ReceiptTypes.READ_PRIVATE, OUR_USER_ID, [event2_1_id], {}
+            self.store.insert_receipt(
+                self.room_id2, receipt_type, OUR_USER_ID, [event2_1_id], {}
             )
         )
         res = self.get_success(
-            self.master_store.get_receipts_for_user(
-                OUR_USER_ID, [ReceiptTypes.READ, ReceiptTypes.READ_PRIVATE]
+            self.store.get_receipts_for_user(
+                OUR_USER_ID, [ReceiptTypes.READ, receipt_type]
             )
         )
         self.assertEqual(res, {self.room_id1: event1_2_id, self.room_id2: event2_1_id})
 
-    def test_get_last_receipt_event_id_for_user(self):
+    @parameterized.expand(
+        [ReceiptTypes.READ_PRIVATE, ReceiptTypes.UNSTABLE_READ_PRIVATE]
+    )
+    def test_get_last_receipt_event_id_for_user(self, receipt_type: str) -> None:
         # Send some events into the first room
         event1_1_id = self.create_and_send_event(
             self.room_id1, UserID.from_string(OTHER_USER_ID)
@@ -194,30 +211,30 @@ class SlavedReceiptTestCase(BaseSlavedStoreTestCase):
 
         # Send public read receipt for the first event
         self.get_success(
-            self.master_store.insert_receipt(
+            self.store.insert_receipt(
                 self.room_id1, ReceiptTypes.READ, OUR_USER_ID, [event1_1_id], {}
             )
         )
         # Send private read receipt for the second event
         self.get_success(
-            self.master_store.insert_receipt(
-                self.room_id1, ReceiptTypes.READ_PRIVATE, OUR_USER_ID, [event1_2_id], {}
+            self.store.insert_receipt(
+                self.room_id1, receipt_type, OUR_USER_ID, [event1_2_id], {}
             )
         )
 
         # Test we get the latest event when we want both private and public receipts
         res = self.get_success(
-            self.master_store.get_last_receipt_event_id_for_user(
+            self.store.get_last_receipt_event_id_for_user(
                 OUR_USER_ID,
                 self.room_id1,
-                [ReceiptTypes.READ, ReceiptTypes.READ_PRIVATE],
+                [ReceiptTypes.READ, receipt_type],
             )
         )
         self.assertEqual(res, event1_2_id)
 
         # Test we get the older event when we want only public receipt
         res = self.get_success(
-            self.master_store.get_last_receipt_event_id_for_user(
+            self.store.get_last_receipt_event_id_for_user(
                 OUR_USER_ID, self.room_id1, [ReceiptTypes.READ]
             )
         )
@@ -225,20 +242,20 @@ class SlavedReceiptTestCase(BaseSlavedStoreTestCase):
 
         # Test we get the latest event when we want only the private receipt
         res = self.get_success(
-            self.master_store.get_last_receipt_event_id_for_user(
-                OUR_USER_ID, self.room_id1, [ReceiptTypes.READ_PRIVATE]
+            self.store.get_last_receipt_event_id_for_user(
+                OUR_USER_ID, self.room_id1, [receipt_type]
             )
         )
         self.assertEqual(res, event1_2_id)
 
         # Test receipt updating
         self.get_success(
-            self.master_store.insert_receipt(
+            self.store.insert_receipt(
                 self.room_id1, ReceiptTypes.READ, OUR_USER_ID, [event1_2_id], {}
             )
         )
         res = self.get_success(
-            self.master_store.get_last_receipt_event_id_for_user(
+            self.store.get_last_receipt_event_id_for_user(
                 OUR_USER_ID, self.room_id1, [ReceiptTypes.READ]
             )
         )
@@ -251,15 +268,15 @@ class SlavedReceiptTestCase(BaseSlavedStoreTestCase):
 
         # Test new room is reflected in what the method returns
         self.get_success(
-            self.master_store.insert_receipt(
-                self.room_id2, ReceiptTypes.READ_PRIVATE, OUR_USER_ID, [event2_1_id], {}
+            self.store.insert_receipt(
+                self.room_id2, receipt_type, OUR_USER_ID, [event2_1_id], {}
             )
         )
         res = self.get_success(
-            self.master_store.get_last_receipt_event_id_for_user(
+            self.store.get_last_receipt_event_id_for_user(
                 OUR_USER_ID,
                 self.room_id2,
-                [ReceiptTypes.READ, ReceiptTypes.READ_PRIVATE],
+                [ReceiptTypes.READ, receipt_type],
             )
         )
         self.assertEqual(res, event2_1_id)
diff --git a/tests/storage/test_roommember.py b/tests/storage/test_roommember.py
index 240b02cb9f..ceec690285 100644
--- a/tests/storage/test_roommember.py
+++ b/tests/storage/test_roommember.py
@@ -23,6 +23,7 @@ from synapse.util import Clock
 
 from tests import unittest
 from tests.server import TestHomeServer
+from tests.test_utils import event_injection
 
 
 class RoomMemberStoreTestCase(unittest.HomeserverTestCase):
@@ -157,6 +158,75 @@ class RoomMemberStoreTestCase(unittest.HomeserverTestCase):
         # Check that alice's display name is now None
         self.assertEqual(row[0]["display_name"], None)
 
+    def test_room_is_locally_forgotten(self):
+        """Test that when the last local user has forgotten a room it is known as forgotten."""
+        # join two local and one remote user
+        self.room = self.helper.create_room_as(self.u_alice, tok=self.t_alice)
+        self.get_success(
+            event_injection.inject_member_event(self.hs, self.room, self.u_bob, "join")
+        )
+        self.get_success(
+            event_injection.inject_member_event(
+                self.hs, self.room, self.u_charlie.to_string(), "join"
+            )
+        )
+        self.assertFalse(
+            self.get_success(self.store.is_locally_forgotten_room(self.room))
+        )
+
+        # local users leave the room and the room is not forgotten
+        self.get_success(
+            event_injection.inject_member_event(
+                self.hs, self.room, self.u_alice, "leave"
+            )
+        )
+        self.get_success(
+            event_injection.inject_member_event(self.hs, self.room, self.u_bob, "leave")
+        )
+        self.assertFalse(
+            self.get_success(self.store.is_locally_forgotten_room(self.room))
+        )
+
+        # first user forgets the room, room is not forgotten
+        self.get_success(self.store.forget(self.u_alice, self.room))
+        self.assertFalse(
+            self.get_success(self.store.is_locally_forgotten_room(self.room))
+        )
+
+        # second (last local) user forgets the room and the room is forgotten
+        self.get_success(self.store.forget(self.u_bob, self.room))
+        self.assertTrue(
+            self.get_success(self.store.is_locally_forgotten_room(self.room))
+        )
+
+    def test_join_locally_forgotten_room(self):
+        """Tests if a user joins a forgotten room the room is not forgotten anymore."""
+        self.room = self.helper.create_room_as(self.u_alice, tok=self.t_alice)
+        self.assertFalse(
+            self.get_success(self.store.is_locally_forgotten_room(self.room))
+        )
+
+        # after leaving and forget the room, it is forgotten
+        self.get_success(
+            event_injection.inject_member_event(
+                self.hs, self.room, self.u_alice, "leave"
+            )
+        )
+        self.get_success(self.store.forget(self.u_alice, self.room))
+        self.assertTrue(
+            self.get_success(self.store.is_locally_forgotten_room(self.room))
+        )
+
+        # after rejoin the room is not forgotten anymore
+        self.get_success(
+            event_injection.inject_member_event(
+                self.hs, self.room, self.u_alice, "join"
+            )
+        )
+        self.assertFalse(
+            self.get_success(self.store.is_locally_forgotten_room(self.room))
+        )
+
 
 class CurrentStateMembershipUpdateTestCase(unittest.HomeserverTestCase):
     def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
diff --git a/tests/storage/test_state.py b/tests/storage/test_state.py
index 8043bdbde2..5564161750 100644
--- a/tests/storage/test_state.py
+++ b/tests/storage/test_state.py
@@ -369,8 +369,8 @@ class StateStoreTestCase(HomeserverTestCase):
         state_dict_ids = cache_entry.value
 
         self.assertEqual(cache_entry.full, False)
-        self.assertEqual(cache_entry.known_absent, {(e1.type, e1.state_key)})
-        self.assertDictEqual(state_dict_ids, {(e1.type, e1.state_key): e1.event_id})
+        self.assertEqual(cache_entry.known_absent, set())
+        self.assertDictEqual(state_dict_ids, {})
 
         ############################################
         # test that things work with a partial cache
@@ -387,7 +387,7 @@ class StateStoreTestCase(HomeserverTestCase):
         )
 
         self.assertEqual(is_all, False)
-        self.assertDictEqual({(e1.type, e1.state_key): e1.event_id}, state_dict)
+        self.assertDictEqual({}, state_dict)
 
         room_id = self.room.to_string()
         (state_dict, is_all,) = self.state_datastore._get_state_for_group_using_cache(
@@ -412,7 +412,7 @@ class StateStoreTestCase(HomeserverTestCase):
         )
 
         self.assertEqual(is_all, False)
-        self.assertDictEqual({(e1.type, e1.state_key): e1.event_id}, state_dict)
+        self.assertDictEqual({}, state_dict)
 
         (state_dict, is_all,) = self.state_datastore._get_state_for_group_using_cache(
             self.state_datastore._state_group_members_cache,
@@ -443,7 +443,7 @@ class StateStoreTestCase(HomeserverTestCase):
         )
 
         self.assertEqual(is_all, False)
-        self.assertDictEqual({(e1.type, e1.state_key): e1.event_id}, state_dict)
+        self.assertDictEqual({}, state_dict)
 
         (state_dict, is_all,) = self.state_datastore._get_state_for_group_using_cache(
             self.state_datastore._state_group_members_cache,
diff --git a/tests/test_server.py b/tests/test_server.py
index 2fe4411401..d2b2d8344a 100644
--- a/tests/test_server.py
+++ b/tests/test_server.py
@@ -104,7 +104,7 @@ class JsonResourceTests(unittest.TestCase):
             self.reactor, FakeSite(res, self.reactor), b"GET", b"/_matrix/foo"
         )
 
-        self.assertEqual(channel.result["code"], b"500")
+        self.assertEqual(channel.code, 500)
 
     def test_callback_indirect_exception(self) -> None:
         """
@@ -130,7 +130,7 @@ class JsonResourceTests(unittest.TestCase):
             self.reactor, FakeSite(res, self.reactor), b"GET", b"/_matrix/foo"
         )
 
-        self.assertEqual(channel.result["code"], b"500")
+        self.assertEqual(channel.code, 500)
 
     def test_callback_synapseerror(self) -> None:
         """
@@ -150,7 +150,7 @@ class JsonResourceTests(unittest.TestCase):
             self.reactor, FakeSite(res, self.reactor), b"GET", b"/_matrix/foo"
         )
 
-        self.assertEqual(channel.result["code"], b"403")
+        self.assertEqual(channel.code, 403)
         self.assertEqual(channel.json_body["error"], "Forbidden!!one!")
         self.assertEqual(channel.json_body["errcode"], "M_FORBIDDEN")
 
@@ -174,7 +174,7 @@ class JsonResourceTests(unittest.TestCase):
             self.reactor, FakeSite(res, self.reactor), b"GET", b"/_matrix/foobar"
         )
 
-        self.assertEqual(channel.result["code"], b"400")
+        self.assertEqual(channel.code, 400)
         self.assertEqual(channel.json_body["error"], "Unrecognized request")
         self.assertEqual(channel.json_body["errcode"], "M_UNRECOGNIZED")
 
@@ -203,7 +203,7 @@ class JsonResourceTests(unittest.TestCase):
             self.reactor, FakeSite(res, self.reactor), b"HEAD", b"/_matrix/foo"
         )
 
-        self.assertEqual(channel.result["code"], b"200")
+        self.assertEqual(channel.code, 200)
         self.assertNotIn("body", channel.result)
 
 
@@ -242,7 +242,7 @@ class OptionsResourceTests(unittest.TestCase):
     def test_unknown_options_request(self) -> None:
         """An OPTIONS requests to an unknown URL still returns 204 No Content."""
         channel = self._make_request(b"OPTIONS", b"/foo/")
-        self.assertEqual(channel.result["code"], b"204")
+        self.assertEqual(channel.code, 204)
         self.assertNotIn("body", channel.result)
 
         # Ensure the correct CORS headers have been added
@@ -262,7 +262,7 @@ class OptionsResourceTests(unittest.TestCase):
     def test_known_options_request(self) -> None:
         """An OPTIONS requests to an known URL still returns 204 No Content."""
         channel = self._make_request(b"OPTIONS", b"/res/")
-        self.assertEqual(channel.result["code"], b"204")
+        self.assertEqual(channel.code, 204)
         self.assertNotIn("body", channel.result)
 
         # Ensure the correct CORS headers have been added
@@ -282,12 +282,12 @@ class OptionsResourceTests(unittest.TestCase):
     def test_unknown_request(self) -> None:
         """A non-OPTIONS request to an unknown URL should 404."""
         channel = self._make_request(b"GET", b"/foo/")
-        self.assertEqual(channel.result["code"], b"404")
+        self.assertEqual(channel.code, 404)
 
     def test_known_request(self) -> None:
         """A non-OPTIONS request to an known URL should query the proper resource."""
         channel = self._make_request(b"GET", b"/res/")
-        self.assertEqual(channel.result["code"], b"200")
+        self.assertEqual(channel.code, 200)
         self.assertEqual(channel.result["body"], b"/res/")
 
 
@@ -314,7 +314,7 @@ class WrapHtmlRequestHandlerTests(unittest.TestCase):
             self.reactor, FakeSite(res, self.reactor), b"GET", b"/path"
         )
 
-        self.assertEqual(channel.result["code"], b"200")
+        self.assertEqual(channel.code, 200)
         body = channel.result["body"]
         self.assertEqual(body, b"response")
 
@@ -334,7 +334,7 @@ class WrapHtmlRequestHandlerTests(unittest.TestCase):
             self.reactor, FakeSite(res, self.reactor), b"GET", b"/path"
         )
 
-        self.assertEqual(channel.result["code"], b"301")
+        self.assertEqual(channel.code, 301)
         headers = channel.result["headers"]
         location_headers = [v for k, v in headers if k == b"Location"]
         self.assertEqual(location_headers, [b"/look/an/eagle"])
@@ -357,7 +357,7 @@ class WrapHtmlRequestHandlerTests(unittest.TestCase):
             self.reactor, FakeSite(res, self.reactor), b"GET", b"/path"
         )
 
-        self.assertEqual(channel.result["code"], b"304")
+        self.assertEqual(channel.code, 304)
         headers = channel.result["headers"]
         location_headers = [v for k, v in headers if k == b"Location"]
         self.assertEqual(location_headers, [b"/no/over/there"])
@@ -378,7 +378,7 @@ class WrapHtmlRequestHandlerTests(unittest.TestCase):
             self.reactor, FakeSite(res, self.reactor), b"HEAD", b"/path"
         )
 
-        self.assertEqual(channel.result["code"], b"200")
+        self.assertEqual(channel.code, 200)
         self.assertNotIn("body", channel.result)
 
 
diff --git a/tests/test_state.py b/tests/test_state.py
index bafd6d1750..504530b49a 100644
--- a/tests/test_state.py
+++ b/tests/test_state.py
@@ -462,6 +462,7 @@ class StateTestCase(unittest.TestCase):
                 state_ids_before_event={
                     (e.type, e.state_key): e.event_id for e in old_state
                 },
+                partial_state=False,
             )
         )
 
@@ -492,6 +493,7 @@ class StateTestCase(unittest.TestCase):
                 state_ids_before_event={
                     (e.type, e.state_key): e.event_id for e in old_state
                 },
+                partial_state=False,
             )
         )
 
diff --git a/tests/test_terms_auth.py b/tests/test_terms_auth.py
index d3c13cf14c..abd7459a8c 100644
--- a/tests/test_terms_auth.py
+++ b/tests/test_terms_auth.py
@@ -53,7 +53,7 @@ class TermsTestCase(unittest.HomeserverTestCase):
         request_data = {"username": "kermit", "password": "monkey"}
         channel = self.make_request(b"POST", self.url, request_data)
 
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, channel.result)
 
         self.assertTrue(channel.json_body is not None)
         self.assertIsInstance(channel.json_body["session"], str)
@@ -96,7 +96,7 @@ class TermsTestCase(unittest.HomeserverTestCase):
 
         # We don't bother checking that the response is correct - we'll leave that to
         # other tests. We just want to make sure we're on the right path.
-        self.assertEqual(channel.result["code"], b"401", channel.result)
+        self.assertEqual(channel.code, 401, channel.result)
 
         # Finish the UI auth for terms
         request_data = {
@@ -112,7 +112,7 @@ class TermsTestCase(unittest.HomeserverTestCase):
         # We're interested in getting a response that looks like a successful
         # registration, not so much that the details are exactly what we want.
 
-        self.assertEqual(channel.result["code"], b"200", channel.result)
+        self.assertEqual(channel.code, 200, channel.result)
 
         self.assertTrue(channel.json_body is not None)
         self.assertIsInstance(channel.json_body["user_id"], str)
diff --git a/tests/unittest.py b/tests/unittest.py
index 66ce92f4a6..975b0a23a7 100644
--- a/tests/unittest.py
+++ b/tests/unittest.py
@@ -28,6 +28,7 @@ from typing import (
     Generic,
     Iterable,
     List,
+    NoReturn,
     Optional,
     Tuple,
     Type,
@@ -39,7 +40,7 @@ from unittest.mock import Mock, patch
 import canonicaljson
 import signedjson.key
 import unpaddedbase64
-from typing_extensions import Protocol
+from typing_extensions import Concatenate, ParamSpec, Protocol
 
 from twisted.internet.defer import Deferred, ensureDeferred
 from twisted.python.failure import Failure
@@ -67,7 +68,7 @@ from synapse.logging.context import (
 from synapse.rest import RegisterServletsFunc
 from synapse.server import HomeServer
 from synapse.storage.keys import FetchKeyResult
-from synapse.types import JsonDict, UserID, create_requester
+from synapse.types import JsonDict, Requester, UserID, create_requester
 from synapse.util import Clock
 from synapse.util.httpresourcetree import create_resource_tree
 
@@ -88,6 +89,10 @@ setup_logging()
 TV = TypeVar("TV")
 _ExcType = TypeVar("_ExcType", bound=BaseException, covariant=True)
 
+P = ParamSpec("P")
+R = TypeVar("R")
+S = TypeVar("S")
+
 
 class _TypedFailure(Generic[_ExcType], Protocol):
     """Extension to twisted.Failure, where the 'value' has a certain type."""
@@ -97,7 +102,7 @@ class _TypedFailure(Generic[_ExcType], Protocol):
         ...
 
 
-def around(target):
+def around(target: TV) -> Callable[[Callable[Concatenate[S, P], R]], None]:
     """A CLOS-style 'around' modifier, which wraps the original method of the
     given instance with another piece of code.
 
@@ -106,11 +111,11 @@ def around(target):
         return orig(*args, **kwargs)
     """
 
-    def _around(code):
+    def _around(code: Callable[Concatenate[S, P], R]) -> None:
         name = code.__name__
         orig = getattr(target, name)
 
-        def new(*args, **kwargs):
+        def new(*args: P.args, **kwargs: P.kwargs) -> R:
             return code(orig, *args, **kwargs)
 
         setattr(target, name, new)
@@ -131,7 +136,7 @@ class TestCase(unittest.TestCase):
         level = getattr(method, "loglevel", getattr(self, "loglevel", None))
 
         @around(self)
-        def setUp(orig):
+        def setUp(orig: Callable[[], R]) -> R:
             # if we're not starting in the sentinel logcontext, then to be honest
             # all future bets are off.
             if current_context():
@@ -144,7 +149,7 @@ class TestCase(unittest.TestCase):
             if level is not None and old_level != level:
 
                 @around(self)
-                def tearDown(orig):
+                def tearDown(orig: Callable[[], R]) -> R:
                     ret = orig()
                     logging.getLogger().setLevel(old_level)
                     return ret
@@ -158,7 +163,7 @@ class TestCase(unittest.TestCase):
             return orig()
 
         @around(self)
-        def tearDown(orig):
+        def tearDown(orig: Callable[[], R]) -> R:
             ret = orig()
             # force a GC to workaround problems with deferreds leaking logcontexts when
             # they are GCed (see the logcontext docs)
@@ -167,7 +172,7 @@ class TestCase(unittest.TestCase):
 
             return ret
 
-    def assertObjectHasAttributes(self, attrs, obj):
+    def assertObjectHasAttributes(self, attrs: Dict[str, object], obj: object) -> None:
         """Asserts that the given object has each of the attributes given, and
         that the value of each matches according to assertEqual."""
         for key in attrs.keys():
@@ -178,12 +183,12 @@ class TestCase(unittest.TestCase):
             except AssertionError as e:
                 raise (type(e))(f"Assert error for '.{key}':") from e
 
-    def assert_dict(self, required, actual):
+    def assert_dict(self, required: dict, actual: dict) -> None:
         """Does a partial assert of a dict.
 
         Args:
-            required (dict): The keys and value which MUST be in 'actual'.
-            actual (dict): The test result. Extra keys will not be checked.
+            required: The keys and value which MUST be in 'actual'.
+            actual: The test result. Extra keys will not be checked.
         """
         for key in required:
             self.assertEqual(
@@ -191,31 +196,31 @@ class TestCase(unittest.TestCase):
             )
 
 
-def DEBUG(target):
+def DEBUG(target: TV) -> TV:
     """A decorator to set the .loglevel attribute to logging.DEBUG.
     Can apply to either a TestCase or an individual test method."""
-    target.loglevel = logging.DEBUG
+    target.loglevel = logging.DEBUG  # type: ignore[attr-defined]
     return target
 
 
-def INFO(target):
+def INFO(target: TV) -> TV:
     """A decorator to set the .loglevel attribute to logging.INFO.
     Can apply to either a TestCase or an individual test method."""
-    target.loglevel = logging.INFO
+    target.loglevel = logging.INFO  # type: ignore[attr-defined]
     return target
 
 
-def logcontext_clean(target):
+def logcontext_clean(target: TV) -> TV:
     """A decorator which marks the TestCase or method as 'logcontext_clean'
 
     ... ie, any logcontext errors should cause a test failure
     """
 
-    def logcontext_error(msg):
+    def logcontext_error(msg: str) -> NoReturn:
         raise AssertionError("logcontext error: %s" % (msg))
 
     patcher = patch("synapse.logging.context.logcontext_error", new=logcontext_error)
-    return patcher(target)
+    return patcher(target)  # type: ignore[call-overload]
 
 
 class HomeserverTestCase(TestCase):
@@ -255,7 +260,7 @@ class HomeserverTestCase(TestCase):
         method = getattr(self, methodName)
         self._extra_config = getattr(method, "_extra_config", None)
 
-    def setUp(self):
+    def setUp(self) -> None:
         """
         Set up the TestCase by calling the homeserver constructor, optionally
         hijacking the authentication system to return a fixed user, and then
@@ -306,7 +311,9 @@ class HomeserverTestCase(TestCase):
                     )
                 )
 
-                async def get_user_by_access_token(token=None, allow_guest=False):
+                async def get_user_by_access_token(
+                    token: Optional[str] = None, allow_guest: bool = False
+                ) -> JsonDict:
                     assert self.helper.auth_user_id is not None
                     return {
                         "user": UserID.from_string(self.helper.auth_user_id),
@@ -314,7 +321,11 @@ class HomeserverTestCase(TestCase):
                         "is_guest": False,
                     }
 
-                async def get_user_by_req(request, allow_guest=False):
+                async def get_user_by_req(
+                    request: SynapseRequest,
+                    allow_guest: bool = False,
+                    allow_expired: bool = False,
+                ) -> Requester:
                     assert self.helper.auth_user_id is not None
                     return create_requester(
                         UserID.from_string(self.helper.auth_user_id),
@@ -339,11 +350,11 @@ class HomeserverTestCase(TestCase):
         if hasattr(self, "prepare"):
             self.prepare(self.reactor, self.clock, self.hs)
 
-    def tearDown(self):
+    def tearDown(self) -> None:
         # Reset to not use frozen dicts.
         events.USE_FROZEN_DICTS = False
 
-    def wait_on_thread(self, deferred, timeout=10):
+    def wait_on_thread(self, deferred: Deferred, timeout: int = 10) -> None:
         """
         Wait until a Deferred is done, where it's waiting on a real thread.
         """
@@ -374,7 +385,7 @@ class HomeserverTestCase(TestCase):
             clock (synapse.util.Clock): The Clock, associated with the reactor.
 
         Returns:
-            A homeserver (synapse.server.HomeServer) suitable for testing.
+            A homeserver suitable for testing.
 
         Function to be overridden in subclasses.
         """
@@ -408,7 +419,7 @@ class HomeserverTestCase(TestCase):
             "/_synapse/admin": servlet_resource,
         }
 
-    def default_config(self):
+    def default_config(self) -> JsonDict:
         """
         Get a default HomeServer config dict.
         """
@@ -421,7 +432,9 @@ class HomeserverTestCase(TestCase):
 
         return config
 
-    def prepare(self, reactor: MemoryReactor, clock: Clock, homeserver: HomeServer):
+    def prepare(
+        self, reactor: MemoryReactor, clock: Clock, homeserver: HomeServer
+    ) -> None:
         """
         Prepare for the test.  This involves things like mocking out parts of
         the homeserver, or building test data common across the whole test
@@ -519,7 +532,7 @@ class HomeserverTestCase(TestCase):
         config_obj.parse_config_dict(config, "", "")
         kwargs["config"] = config_obj
 
-        async def run_bg_updates():
+        async def run_bg_updates() -> None:
             with LoggingContext("run_bg_updates"):
                 self.get_success(stor.db_pool.updates.run_background_updates(False))
 
@@ -538,11 +551,7 @@ class HomeserverTestCase(TestCase):
         """
         self.reactor.pump([by] * 100)
 
-    def get_success(
-        self,
-        d: Awaitable[TV],
-        by: float = 0.0,
-    ) -> TV:
+    def get_success(self, d: Awaitable[TV], by: float = 0.0) -> TV:
         deferred: Deferred[TV] = ensureDeferred(d)  # type: ignore[arg-type]
         self.pump(by=by)
         return self.successResultOf(deferred)
@@ -668,14 +677,29 @@ class HomeserverTestCase(TestCase):
         username: str,
         password: str,
         device_id: Optional[str] = None,
+        additional_request_fields: Optional[Dict[str, str]] = None,
         custom_headers: Optional[Iterable[CustomHeaderType]] = None,
     ) -> str:
         """
         Log in a user, and get an access token. Requires the Login API be registered.
+
+        Args:
+            username: The localpart to assign to the new user.
+            password: The password to assign to the new user.
+            device_id: An optional device ID to assign to the new device created during
+                login.
+            additional_request_fields: A dictionary containing any additional /login
+                request fields and their values.
+            custom_headers: Custom HTTP headers and values to add to the /login request.
+
+        Returns:
+            The newly registered user's Matrix ID.
         """
         body = {"type": "m.login.password", "user": username, "password": password}
         if device_id:
             body["device_id"] = device_id
+        if additional_request_fields:
+            body.update(additional_request_fields)
 
         channel = self.make_request(
             "POST",
@@ -755,7 +779,7 @@ class FederatingHomeserverTestCase(HomeserverTestCase):
     OTHER_SERVER_NAME = "other.example.com"
     OTHER_SERVER_SIGNATURE_KEY = signedjson.key.generate_signing_key("test")
 
-    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer):
+    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
         super().prepare(reactor, clock, hs)
 
         # poke the other server's signing key into the key store, so that we don't
@@ -879,7 +903,7 @@ def _auth_header_for_request(
     )
 
 
-def override_config(extra_config):
+def override_config(extra_config: JsonDict) -> Callable[[TV], TV]:
     """A decorator which can be applied to test functions to give additional HS config
 
     For use
@@ -892,12 +916,13 @@ def override_config(extra_config):
                 ...
 
     Args:
-        extra_config(dict): Additional config settings to be merged into the default
+        extra_config: Additional config settings to be merged into the default
             config dict before instantiating the test homeserver.
     """
 
-    def decorator(func):
-        func._extra_config = extra_config
+    def decorator(func: TV) -> TV:
+        # This attribute is being defined.
+        func._extra_config = extra_config  # type: ignore[attr-defined]
         return func
 
     return decorator
diff --git a/tests/util/test_dict_cache.py b/tests/util/test_dict_cache.py
index bee66dee43..e8b6246ab5 100644
--- a/tests/util/test_dict_cache.py
+++ b/tests/util/test_dict_cache.py
@@ -20,7 +20,7 @@ from tests import unittest
 
 class DictCacheTestCase(unittest.TestCase):
     def setUp(self):
-        self.cache = DictionaryCache("foobar")
+        self.cache = DictionaryCache("foobar", max_entries=10)
 
     def test_simple_cache_hit_full(self):
         key = "test_simple_cache_hit_full"
@@ -76,13 +76,13 @@ class DictCacheTestCase(unittest.TestCase):
 
         seq = self.cache.sequence
         test_value_1 = {"test": "test_simple_cache_hit_miss_partial"}
-        self.cache.update(seq, key, test_value_1, fetched_keys=set("test"))
+        self.cache.update(seq, key, test_value_1, fetched_keys={"test"})
 
         seq = self.cache.sequence
         test_value_2 = {"test2": "test_simple_cache_hit_miss_partial2"}
-        self.cache.update(seq, key, test_value_2, fetched_keys=set("test2"))
+        self.cache.update(seq, key, test_value_2, fetched_keys={"test2"})
 
-        c = self.cache.get(key)
+        c = self.cache.get(key, dict_keys=["test", "test2"])
         self.assertEqual(
             {
                 "test": "test_simple_cache_hit_miss_partial",
@@ -90,3 +90,30 @@ class DictCacheTestCase(unittest.TestCase):
             },
             c.value,
         )
+        self.assertEqual(c.full, False)
+
+    def test_invalidation(self):
+        """Test that the partial dict and full dicts get invalidated
+        separately.
+        """
+        key = "some_key"
+
+        seq = self.cache.sequence
+        # start by populating a "full dict" entry
+        self.cache.update(seq, key, {"a": "b", "c": "d"})
+
+        # add a bunch of individual entries, also keeping the individual
+        # entry for "a" warm.
+        for i in range(20):
+            self.cache.get(key, ["a"])
+            self.cache.update(seq, f"key{i}", {1: 2})
+
+        # We should have evicted the full dict...
+        r = self.cache.get(key)
+        self.assertFalse(r.full)
+        self.assertTrue("c" not in r.value)
+
+        # ... but kept the "a" entry that we kept querying.
+        r = self.cache.get(key, dict_keys=["a"])
+        self.assertFalse(r.full)
+        self.assertEqual(r.value, {"a": "b"})