1 files changed, 8 insertions, 0 deletions
diff --git a/synapse/federation/sender/per_destination_queue.py b/synapse/federation/sender/per_destination_queue.py
index 89df9a619b..e9c8a9f20a 100644
--- a/synapse/federation/sender/per_destination_queue.py
+++ b/synapse/federation/sender/per_destination_queue.py
@@ -29,6 +29,7 @@ from synapse.api.presence import UserPresenceState
 from synapse.events import EventBase
 from synapse.federation.units import Edu
 from synapse.handlers.presence import format_user_presence_state
+from synapse.logging.opentracing import SynapseTags, set_tag
 from synapse.metrics import sent_transactions_counter
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.types import ReadReceipt
@@ -557,6 +558,13 @@ class PerDestinationQueue:
         contents, stream_id = await self._store.get_new_device_msgs_for_remote(
             self._destination, last_device_stream_id, to_device_stream_id, limit
         )
+        for content in contents:
+            message_id = content.get("message_id")
+            if not message_id:
+                continue
+
+            set_tag(SynapseTags.TO_DEVICE_MESSAGE_ID, message_id)
+
         edus = [
             Edu(
                 origin=self._server_name,