multiple runtime bugfixes for 1.5.5+65

lib/view/pages/talk/details/chat_info.dart

@@ -39,6 +39,7 @@ class _ChatInfoState extends State<ChatInfo> {
     GetParticipantsCache(
       chatToken: widget.room.token,
       onUpdate: (GetParticipantsResponse data) {
+        if (!mounted) return;
         setState(() {
           participants = data;
         });