diff --git a/lib/home.dart b/lib/home.dart
index e536470b..3dc71bd9 100644
--- a/lib/home.dart
+++ b/lib/home.dart
@@ -191,20 +191,15 @@ class _HomeState extends State<Home> {
           search,
           me,
         ];
-        break;
       case PlatformType.gitlab:
         return [explore, group, search, me];
-        break;
       case PlatformType.bitbucket:
         return [explore, group, me];
-        break;
       case PlatformType.gitea:
         return [group, me];
-        break;
       case PlatformType.gitee:
       case PlatformType.gogs:
         return [search, me];
-        break;
       default:
         return [];
     }
diff --git a/lib/scaffolds/list_stateful.dart b/lib/scaffolds/list_stateful.dart
index 8981cc77..e307fb7c 100644
--- a/lib/scaffolds/list_stateful.dart
+++ b/lib/scaffolds/list_stateful.dart
@@ -26,7 +26,7 @@ class ListStatefulScaffold<T, K> extends StatefulWidget {
   final Widget title;
   final Widget Function()? actionBuilder;
   final Widget Function(T payload) itemBuilder;
-  final Future<ListPayload<T, K>> Function(K cursor) fetch;
+  final Future<ListPayload<T, K>> Function(K? cursor) fetch;
 
   ListStatefulScaffold({
     required this.title,
@@ -41,7 +41,7 @@ class ListStatefulScaffold<T, K> extends StatefulWidget {
 }
 
 class _ListStatefulScaffoldState<T, K>
-    extends State<ListStatefulScaffold<T, K?>> {
+    extends State<ListStatefulScaffold<T, K>> {
   bool loading = false;
   bool loadingMore = false;
   String error = '';
diff --git a/lib/scaffolds/refresh_stateful.dart b/lib/scaffolds/refresh_stateful.dart
index 1d2e6151..8b6e51c7 100644
--- a/lib/scaffolds/refresh_stateful.dart
+++ b/lib/scaffolds/refresh_stateful.dart
@@ -7,7 +7,8 @@ class RefreshStatefulScaffold<T> extends StatefulWidget {
   final Widget title;
   final Widget? Function(T data, void Function(T newData) setData) bodyBuilder;
   final Future<T> Function() fetch;
-  final Widget? Function(T data, void Function(T newData) setData)? actionBuilder;
+  final Widget? Function(T data, void Function(T newData) setData)?
+      actionBuilder;
   final Widget? action;
   final canRefresh;
 
@@ -26,7 +27,7 @@ class RefreshStatefulScaffold<T> extends StatefulWidget {
 }
 
 class _RefreshStatefulScaffoldState<T>
-    extends State<RefreshStatefulScaffold<T?>> {
+    extends State<RefreshStatefulScaffold<T>> {
   // bool _loading;
   T? _data;
   String _error = '';
@@ -60,7 +61,7 @@ class _RefreshStatefulScaffoldState<T>
   Widget? get _action {
     if (widget.action != null) return widget.action;
     if (widget.actionBuilder == null || _data == null) return null;
-    return widget.actionBuilder!(_data, (v) {
+    return widget.actionBuilder!(_data!, (v) {
       setState(() {
         _data = v;
       });
@@ -70,7 +71,7 @@ class _RefreshStatefulScaffoldState<T>
   @override
   Widget build(BuildContext context) {
     Widget child = ErrorLoadingWrapper(
-      bodyBuilder: () => widget.bodyBuilder(_data, (v) {
+      bodyBuilder: () => widget.bodyBuilder(_data!, (v) {
         setState(() {
           _data = v;
         });
diff --git a/lib/scaffolds/tab_stateful.dart b/lib/scaffolds/tab_stateful.dart
index dc32598c..1823c0b2 100644
--- a/lib/scaffolds/tab_stateful.dart
+++ b/lib/scaffolds/tab_stateful.dart
@@ -22,7 +22,7 @@ class TabStatefulScaffold<T> extends StatefulWidget {
   _TabStatefulScaffoldState<T> createState() => _TabStatefulScaffoldState();
 }
 
-class _TabStatefulScaffoldState<T> extends State<TabStatefulScaffold<T?>> {
+class _TabStatefulScaffoldState<T> extends State<TabStatefulScaffold<T>> {
   late bool _loading;
   T? _payload0;
   T? _payload1;
@@ -90,7 +90,7 @@ class _TabStatefulScaffoldState<T> extends State<TabStatefulScaffold<T?>> {
       title: widget.title,
       action: widget.actionBuilder == null
           ? null
-          : widget.actionBuilder!(_payload, _refresh),
+          : widget.actionBuilder!(_payload!, _refresh),
       tabs: widget.tabs,
       activeTab: _activeTab,
       onTabSwitch: (selected) async {
@@ -105,7 +105,7 @@ class _TabStatefulScaffoldState<T> extends State<TabStatefulScaffold<T?>> {
       },
       onRefresh: _refresh,
       body: ErrorLoadingWrapper(
-        bodyBuilder: () => widget.bodyBuilder(_payload, _activeTab),
+        bodyBuilder: () => widget.bodyBuilder(_payload!, _activeTab),
         error: _error,
         loading: _payload == null,
         reload: _refresh,
diff --git a/lib/screens/gh_notification.dart b/lib/screens/gh_notification.dart
index c6fd9993..d2756afd 100644
--- a/lib/screens/gh_notification.dart
+++ b/lib/screens/gh_notification.dart
@@ -20,7 +20,7 @@ class GhNotificationScreen extends StatefulWidget {
 }
 
 class GhNotificationScreenState extends State<GhNotificationScreen> {
-  Future<Map<String?, NotificationGroup>> fetchNotifications(int index) async {
+  Future<Map<String, NotificationGroup>> fetchNotifications(int index) async {
     final ns = await context.read<AuthModel>().ghClient!.getJSON(
           '/notifications?all=${index == 2}&participating=${index == 1}',
           convert: (dynamic vs) =>
@@ -30,10 +30,10 @@ class GhNotificationScreenState extends State<GhNotificationScreen> {
       context.read<NotificationModel>().setCount(ns.length);
     }
 
-    Map<String?, NotificationGroup> _groupMap = {};
+    Map<String, NotificationGroup> _groupMap = {};
 
     ns.forEach((item) {
-      final repo = item.repository!.fullName;
+      final repo = item.repository!.fullName ?? ''; // TODO: nullable
       if (_groupMap[repo] == null) {
         _groupMap[repo] = NotificationGroup(repo);
       }
@@ -155,7 +155,7 @@ ${item.key}: pullRequest(number: ${item.subject!.number}) {
 
   @override
   Widget build(context) {
-    return TabStatefulScaffold(
+    return TabStatefulScaffold<Map<String, NotificationGroup>>(
       title: AppBarTitle(AppLocalizations.of(context)!.notification),
       tabs: [
         AppLocalizations.of(context)!.unread,
diff --git a/lib/widgets/notification_item.dart b/lib/widgets/notification_item.dart
index cc1070c4..967df160 100644
--- a/lib/widgets/notification_item.dart
+++ b/lib/widgets/notification_item.dart
@@ -42,7 +42,6 @@ class _NotificationItemState extends State<NotificationItem> {
           default:
             return _buildIcon(Octicons.person);
         }
-        break;
       case 'PullRequest':
         switch (payload.state) {
           case 'OPEN':
@@ -54,7 +53,6 @@ class _NotificationItemState extends State<NotificationItem> {
           default:
             return _buildIcon(Octicons.person);
         }
-        break;
       // color: Color.fromRGBO(0x6f, 0x42, 0xc1, 1),
       case 'Release':
         return _buildIcon(Octicons.tag);
diff --git a/pubspec.lock b/pubspec.lock
index e35888ea..9ad1ba9e 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -28,7 +28,7 @@ packages:
       name: async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.5.0"
+    version: "2.6.1"
   boolean_selector:
     dependency: transitive
     description:
@@ -760,7 +760,7 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0"
+    version: "1.8.1"
   stack_trace:
     dependency: transitive
     description:
@@ -802,7 +802,7 @@ packages:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.2.19"
+    version: "0.3.0"
   timeago:
     dependency: "direct main"
     description: