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Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

synapse/config/workers.py

@@ -145,7 +145,6 @@ class WriterLocations:
         device_lists: The instances that write to the device list stream.
         thread_subscriptions: The instances that write to the thread subscriptions
             stream.
-        profile_updates: The instances that write to the profile updates stream.
         quarantined_media_changes: The instances that write to the quarantined media
              changes stream.
     """

synapse/handlers/sync.py

@@ -2416,10 +2416,15 @@ class SyncHandler:
                         # user ID + field name + value, which ensures if the value
                         # changes, we'll miss the cache, thus sending the field update
                         # to the syncing user.
+                        import json
+
                         cache_value = hashlib.sha256(
-                            f"{other_user_id}-{field_name}-{profile_data.get(field_name)}".encode(
-                                "utf8"
-                            )
+                            json.dumps(
+                                [other_user_id, field_name, profile_data.get(field_name)],
+                                sort_keys=True,
+                                separators=(",", ":"),
+                                ensure_ascii=False,
+                            ).encode("utf8")
                         ).hexdigest()
                         if cache.get(cache_value) is None:
                             per_user_updates[field_name] = profile_data.get(field_name)

synapse/storage/databases/main/profile.py

@@ -884,10 +884,12 @@ class ProfileWorkerStore(SQLBaseStore):
             values=values,
         )
 
-        # Add per user tracking rows pointing to the latest stream ID
+        # Add per user tracking rows for each generated stream ID
         inserted_ts = self.clock.time_msec()
         per_user_values = [
-            (stream_ids[-1], user_id, inserted_ts) for user_id in target_users
+            (stream_id, user_id, inserted_ts)
+            for user_id in target_users
+            for stream_id in stream_ids
         ]
         self.db_pool.simple_insert_many_txn(
             txn,
@@ -1049,25 +1051,20 @@ class ProfileWorkerStore(SQLBaseStore):
         )
         res = txn.fetchall()
         if res:
-            stream_ids = [row[0] for row in res]
-
             user_clause, user_args = make_in_list_sql_clause(
                 txn.database_engine,
                 "user_id",
                 users_to_update,
             )
-            stream_id_clause, stream_id_args = make_in_list_sql_clause(
-                txn.database_engine,
-                "stream_id",
-                stream_ids,
-            )
             txn.execute(
                 f"""
                     DELETE FROM profile_updates_per_user
                         WHERE {user_clause}
-                        AND {stream_id_clause}
+                        AND stream_id IN (
+                            SELECT stream_id FROM profile_updates WHERE user_id = ?
+                        )
                 """,
-                (*user_args, *stream_id_args),
+                (*user_args, user_id.to_string()),
             )
 
         # Now record the "left room" action in the stream