Synapse error logged on opening client (room list handler)

[V02460]

Whenever I open up a client, this error is emitted to Synapse’s logs:

AttributeError: 'NoneType' object has no attribute 'content'

The code line at fault is in the room list handler. It seems to assume there is always a create event returned from the database, which in my case appears to fail:

synapse/synapse/handlers/room_list.py

Lines 284 to 285 in 883ac4b

	create_event = current_state.get((EventTypes.Create, ""))
	result["m.federate"] = create_event.content.get("m.federate", True)

I am running Synapse v1.12.3.

[clokep]

I think this is a duplicate of #4891, but it is hard to tell without the full stack trace. It seems to point to the same line of code though so I'm going to close this as a duplicate. Please reopen it if this seems to be a different issue.