Change the parameter immediate of send_device_messages to default to True

changelog.d/15297.bugfix

@@ -0,0 +1 @@
+Fix a bug introduced in Synapse v1.55.0 which could delay remote homeservers being able to decrypt encrypted messages sent by local users.

synapse/federation/send_queue.py

@@ -244,7 +244,7 @@ def send_presence_to_destinations(
 
         self.notifier.on_new_replication_data()
 
-    def send_device_messages(self, destination: str, immediate: bool = False) -> None:
+    def send_device_messages(self, destination: str, immediate: bool = True) -> None:
         """As per FederationSender"""
         # We don't need to replicate this as it gets sent down a different
         # stream.

synapse/federation/sender/__init__.py

@@ -783,7 +783,7 @@ def send_edu(self, edu: Edu, key: Optional[Hashable]) -> None:
         else:
             queue.send_edu(edu)
 
-    def send_device_messages(self, destination: str, immediate: bool = False) -> None:
+    def send_device_messages(self, destination: str, immediate: bool = True) -> None:
         if destination == self.server_name:
             logger.warning("Not sending device update to ourselves")
             return