2 files changed, 1 insertions, 2 deletions
diff --git a/synapse/api/filtering.py b/synapse/api/filtering.py
index 0d8957175d..f3a056110f 100644
--- a/synapse/api/filtering.py
+++ b/synapse/api/filtering.py
@@ -454,7 +454,7 @@ class Filter(object):
             filter: A new filter including the given rooms and the old
                     filter's rooms.
         """
-        newFilter = self
+        newFilter = Filter(self.filter_json)
         newFilter.rooms += room_ids
         return newFilter
 
diff --git a/synapse/storage/state.py b/synapse/storage/state.py
index b064671851..981d1e3600 100644
--- a/synapse/storage/state.py
+++ b/synapse/storage/state.py
@@ -448,7 +448,6 @@ class StateGroupWorkerStore(EventsWorkerStore, SQLBaseStore):
         Returns:
             Deferred[str]: predecessor room id
         """
-
         state_ids = yield self.get_current_state_ids(room_id)
         create_id = state_ids.get((EventTypes.Create, ""))