Use temporary prefixes as per the MSC

synapse/handlers/sync.py

@@ -1895,7 +1895,9 @@ class SyncHandler(object):
                 if notifs is not None:
                     unread_notifications["notification_count"] = notifs["notify_count"]
                     unread_notifications["highlight_count"] = notifs["highlight_count"]
-                    unread_notifications["unread_count"] = notifs["unread_count"]
+                    unread_notifications["org.matrix.msc2625.unread_count"] = (
+                        notifs["unread_count"]
+                    )
 
                 sync_result_builder.joined.append(room_sync)
 

synapse/rest/client/v1/push_rule.py

@@ -267,7 +267,7 @@ def _check_actions(actions):
         raise InvalidRuleException("No actions found")
 
     for a in actions:
-        if a in ["notify", "dont_notify", "coalesce", "mark_unread"]:
+        if a in ["notify", "dont_notify", "coalesce", "org.matrix.msc2625.mark_unread"]:
             pass
         elif isinstance(a, dict) and "set_tweak" in a:
             pass

synapse/storage/data_stores/main/event_push_actions.py

@@ -454,7 +454,7 @@ class EventPushActionsWorkerStore(SQLBaseStore):
         # can be used to insert into the `event_push_actions_staging` table.
         def _gen_entry(user_id, actions):
             is_highlight = 1 if _action_has_highlight(actions) else 0
-            notif = 0 if "mark_unread" in actions else 1
+            notif = 0 if "org.matrix.msc2625.mark_unread" in actions else 1
             return (
                 event_id,  # event_id column
                 user_id,  # user_id column