From 35c01042db7f6aab1fd84b0a3475a616d927c615 Mon Sep 17 00:00:00 2001
From: Neil Alexander <neilalexander@users.noreply.github.com>
Date: Fri, 1 Apr 2022 15:54:23 +0100
Subject: [PATCH] Check existence of state key for membership events

---
 syncapi/streams/stream_pdu.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/syncapi/streams/stream_pdu.go b/syncapi/streams/stream_pdu.go
index 8215e0977..d23209af3 100644
--- a/syncapi/streams/stream_pdu.go
+++ b/syncapi/streams/stream_pdu.go
@@ -255,7 +255,7 @@ func (p *PDUStreamProvider) addRoomDeltaToResponse(
 
 	hasMembershipChange := false
 	for _, recentEvent := range recentStreamEvents {
-		if recentEvent.Type() == gomatrixserverlib.MRoomMember {
+		if recentEvent.Type() == gomatrixserverlib.MRoomMember && recentEvent.StateKey() != nil {
 			hasMembershipChange = true
 			break
 		}