🐛 Fix editing message

lib/controllers/chat_message_controller.dart

@@ -214,7 +214,7 @@ class ChatMessageController extends ChangeNotifier {
           final idx =
               messages.indexWhere((x) => x.id == message.relatedEventId);
           if (idx != -1) {
-            final newBody = message.body;
+            final newBody = Map<String, dynamic>.from(message.body);
             newBody.remove('related_event');
             messages[idx] = messages[idx].copyWith(
               body: newBody,

lib/screens/chat.dart

@@ -41,6 +41,7 @@ class _ChatScreenState extends State<ChatScreen> {
   Future<void> _fetchWhatsNew() async {
     final sn = context.read<SnNetworkProvider>();
     final resp = await sn.client.get('/cgi/im/whats-new');
+    if (resp.data == null) return;
     final List<dynamic> out = resp.data;
     setState(() {
       _unreadCounts = {for (var v in out) v['channel_id']: v['count']};