Fix leaving call with screenshare active

src/Room.jsx

@@ -400,8 +400,11 @@ function InRoomView({
       const participant = participants.find(
         (p) => p.usermediaCallFeed.userId === callFeed.userId
       );
+
+      if (participant) {
         participant.screenshareCallFeed = callFeed;
       }
+    }
 
     return participants;
   }, [userMediaFeeds, activeSpeaker, screenshareFeeds]);