implemented dual Nextcloud push registration with separate general and talk apptypes to ensure reliable Talk notification delivery; introduced stacked MessagingStyle notifications for chat threads with support for circular conversation avatars and disk caching

android/app/src/main/AndroidManifest.xml

@@ -48,6 +48,17 @@
             android:name="flutterEmbedding"
             android:value="2" />
 
+        <!-- Fallback small icon + accent for anything FCM ever renders itself
+             (e.g. plain notification messages). Launcher mipmaps are unusable
+             as small icons: Android only draws their alpha silhouette, which
+             shows up as a solid circle in the status bar. -->
+        <meta-data
+            android:name="com.google.firebase.messaging.default_notification_icon"
+            android:resource="@drawable/ic_stat_notification" />
+        <meta-data
+            android:name="com.google.firebase.messaging.default_notification_color"
+            android:resource="@color/notification_accent" />
+
         <!-- Receiver classes live at the package root (NOT under .widgets) because
              the home_widget Flutter plugin resolves them as <app-package>.<name>. -->
         <receiver

android/app/src/main/res/drawable/ic_stat_notification.xml

@@ -0,0 +1,34 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  Status-bar small icon: monochrome Marianum M, ported from
+  marianum_m_watermark.xml (same path + nested transforms). Android renders
+  only the alpha channel of small icons, so the fill is hard white and never
+  tinted at runtime. 24dp with the source's non-square viewport — the system
+  fits it into the icon bounds.
+-->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="70.000168"
+    android:viewportHeight="82.227348">
+
+    <group
+        android:scaleX="0.26458333"
+        android:scaleY="0.26458334"
+        android:translateX="107.44411"
+        android:translateY="-80.482198">
+        <group
+            android:translateX="-749.41293"
+            android:translateY="290.52252">
+            <group
+                android:scaleX="0.13333333"
+                android:scaleY="-0.13333333"
+                android:translateX="0"
+                android:translateY="632.14667">
+                <path
+                    android:fillColor="#FFFFFFFF"
+                    android:pathData="M 3499.67,4594.33 c -16.43,-106.19 -29.71,-199.97 -43.79,-293.49 86.83,-19 138.5,-27.61 223.38,-43.82 63.81,-12.18 175.24,-20.4 179.64,-83.23 6.46,-92.69 -124.69,-55.41 -188.38,-43.81 -84.33,15.36 -159.13,28.84 -232.2,43.81 -13.68,-60.72 -26.83,-118.68 -39.43,-179.61 -36.76,-178.32 -73.67,-368.16 -105.11,-551.97 18.09,25.66 30.84,42.72 43.8,65.7 66.7,118.26 140.39,245.04 227.76,354.83 33.49,42.05 76.86,94.81 118.31,113.91 98.42,45.36 166.68,-22.2 170.87,-118.28 3.68,-85.28 -23.09,-181.17 -35.08,-275.99 -12.4,-98.19 -22.89,-194.93 -35.03,-275.98 72.44,102.69 147.93,269.64 240.95,381.12 27.51,33 73.55,80.61 118.27,87.62 218.76,34.33 126.58,-312.17 127.05,-473.13 0.4,-144.9 44.01,-255.37 175.21,-271.59 43.02,-5.31 105.84,11.16 112.7,-26.34 8.67,-47.38 -78.15,-60.52 -125.84,-61.28 -291.34,-4.51 -322.06,262.33 -311.01,573.88 -19.85,-18.57 -35.71,-47.53 -52.57,-74.47 -97.59,-155.88 -203.95,-327.22 -297.92,-503.79 -25.93,-48.79 -53.68,-114.7 -135.8,-83.23 -17.27,6.63 -48.25,44.39 -52.56,56.96 -19.58,57.19 1.55,137.42 8.76,205.89 21.54,203.72 57.81,389.09 78.87,587.01 -26.3,0.51 -43.93,-30.07 -56.96,-48.2 -46.9,-65.27 -86.02,-140.76 -127.04,-214.64 -52.84,-95.15 -108.23,-192.84 -157.71,-293.52 -75.25,-153.09 -188.6,-501.89 -242.12,-678.81 -8.67,-28.67 -17.7,-58.08 -26.3,-87.64 -7.48,-25.72 -10.39,-57.68 -35.05,-74.46 -100.02,18.93 -89.71,104.89 -70.09,205.9 47.35,243.43 170.89,706.45 211.48,946.04 -72.97,-70.97 -153.99,-207.41 -289.14,-236.55 -136.47,-29.44 -217.95,47.68 -271.6,122.66 -17.14,23.96 -41.43,49.54 -26.29,78.84 83.96,35.51 113.37,-65.2 197.15,-74.47 22.65,-2.5 54.56,2.4 74.46,8.78 132.4,42.34 237.57,218.76 297.87,346.07 74.16,156.45 125.32,330.5 148.95,490.64 -65.71,11.4 -142.96,22.15 -219.25,36.52 -109.8,20.72 -158.81,10.75 -201.29,59.86 9.15,41.95 41.41,60.8 70.1,83.24 126.26,-16.84 252.45,-33.77 372.36,-56.97 20.43,89.25 51.98,218.51 74.45,311.05 40.53,26.02 88.88,-8.43 105.17,-35.06 z" />
+            </group>
+        </group>
+    </group>
+</vector>

android/app/src/main/res/values/colors.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <!-- Brand accent for notifications; mirrors LightAppTheme.marianumRed
+         (Color.fromARGB(255, 153, 51, 51)). Used as the FCM default
+         notification color and must stay in sync with the Dart constant. -->
+    <color name="notification_accent">#993333</color>
+</resources>

lib/api/marianumcloud/app_password/delete_app_password.dart

@@ -2,19 +2,24 @@ import 'package:http/http.dart' as http;
 
 import '../nextcloud_ocs.dart';
 
-/// Revokes the current app password server-side via
-/// `DELETE /ocs/v2.php/core/apppassword`. Best-effort: the shared OCS headers
-/// authenticate with the app password itself (it revokes the credential it was
-/// made with) and the result is ignored — logout clears local state regardless.
+/// Revokes an app password server-side via
+/// `DELETE /ocs/v2.php/core/apppassword`. The endpoint revokes the credential
+/// the request authenticates WITH — by default the shared OCS headers (general
+/// app password); pass [authorizationHeader] to revoke another one (the Talk
+/// app password). Best-effort: the result is ignored — logout clears local
+/// state regardless.
 class DeleteAppPassword {
   final http.Client _client;
 
   DeleteAppPassword({http.Client? client}) : _client = client ?? http.Client();
 
-  Future<void> run() async {
+  Future<void> run({String? authorizationHeader}) async {
     await _client.delete(
       NextcloudOcs.uri('core/apppassword'),
-      headers: NextcloudOcs.headers(),
+      headers: {
+        ...NextcloudOcs.headers(),
+        'Authorization': ?authorizationHeader,
+      },
     );
   }
 }

lib/api/marianumconnect/queries/push_device_register/push_device_register.dart

@@ -19,6 +19,7 @@ class PushDeviceRegister {
     required String userPublicKey,
     required String pushToken,
     required String platform,
+    required String registrationType,
     String? appVersion,
   }) async {
     try {
@@ -30,6 +31,9 @@ class PushDeviceRegister {
           'userPublicKey': userPublicKey,
           'pushToken': pushToken,
           'platform': platform,
+          // 'general' | 'talk' — the backend derives the NC hash comparison
+          // value from it (general = sha512(token), talk = sha512(token+'#talk')).
+          'registrationType': registrationType,
           'appVersion': ?appVersion,
         },
       );

lib/main.dart

@@ -96,7 +96,7 @@ Future<void> main() async {
   // decrypts and renders Nextcloud pushes while the app is not in foreground.
   await NotificationService().initializeNotifications();
   await PushRenderer.ensureChannels();
-  FirebaseMessaging.onBackgroundMessage(PushMessageHandler.onBackgroundMessage);
+  FirebaseMessaging.onBackgroundMessage(pushOnBackgroundMessage);
 
   // Wire up the home-screen widget bridge before runApp so any widget render
   // triggered during startup hits initialised native storage.
@@ -375,13 +375,13 @@ class _MainState extends State<Main> {
                       return Stack(
                         fit: StackFit.expand,
                         children: [
-                          if (_appMounted) const App(key: ValueKey('app-shell')),
+                          if (_appMounted)
+                            const App(key: ValueKey('app-shell')),
                           if (_showPostLoginSplash)
                             PostLoginSplash(
                               key: const ValueKey('post-login-splash'),
-                              onComplete: () => setState(
-                                () => _showPostLoginSplash = false,
-                              ),
+                              onComplete: () =>
+                                  setState(() => _showPostLoginSplash = false),
                             ),
                         ],
                       );

lib/model/account_data.dart

@@ -11,9 +11,13 @@ import '../push/push_secure_storage.dart';
 class AccountData {
   static const _usernameField = 'username';
   static const _passwordField = 'password';
-  // App password lives in the push-shared (group-scoped) keystore so the iOS
+  // App passwords live in the push-shared (group-scoped) keystore so the iOS
   // Notification Service Extension can authenticate Nextcloud calls too.
+  // The talk password authenticates the second (apptype=talk) push
+  // registration — Nextcloud binds each push subscription to its session
+  // token, so two registrations need two app passwords.
   static const _appPasswordField = 'nextcloud_app_password';
+  static const _appPasswordTalkField = 'nextcloud_app_password_talk';
 
   static const FlutterSecureStorage _secureStorage = FlutterSecureStorage();
 
@@ -29,6 +33,7 @@ class AccountData {
   String? _username;
   String? _password;
   String? _appPassword;
+  String? _appPasswordTalk;
 
   String getUsername() {
     if (_username == null) throw Exception('Username not initialized');
@@ -65,9 +70,11 @@ class AccountData {
     _username = null;
     _password = null;
     _appPassword = null;
+    _appPasswordTalk = null;
     await _secureStorage.delete(key: _usernameField);
     await _secureStorage.delete(key: _passwordField);
     await _clearAppPasswordStorage();
+    await _clearAppPasswordTalkStorage();
   }
 
   /// Persists a freshly minted Nextcloud app password. After this every
@@ -90,6 +97,28 @@ class AccountData {
 
   bool hasAppPassword() => _appPassword != null && _appPassword!.isNotEmpty;
 
+  /// Persists the app password backing the Talk push registration.
+  Future<void> setAppPasswordTalk(String appPassword) async {
+    _appPasswordTalk = appPassword;
+    try {
+      await pushSecureStorage.write(
+        key: _appPasswordTalkField,
+        value: appPassword,
+      );
+    } on Object {
+      // Group-scoped keystore may be unavailable — in-memory still works for
+      // this session, matching setAppPassword.
+    }
+  }
+
+  Future<void> clearAppPasswordTalk() async {
+    _appPasswordTalk = null;
+    await _clearAppPasswordTalkStorage();
+  }
+
+  bool hasAppPasswordTalk() =>
+      _appPasswordTalk != null && _appPasswordTalk!.isNotEmpty;
+
   Future<void> _clearAppPasswordStorage() async {
     try {
       await pushSecureStorage.delete(key: _appPasswordField);
@@ -98,14 +127,26 @@ class AccountData {
     }
   }
 
+  Future<void> _clearAppPasswordTalkStorage() async {
+    try {
+      await pushSecureStorage.delete(key: _appPasswordTalkField);
+    } on Object {
+      // ignore — nothing stored or keystore unavailable
+    }
+  }
+
   Future<void> _migrateAndLoad() async {
     await _migrateFromLegacyStorage();
     _username = await _secureStorage.read(key: _usernameField);
     _password = await _secureStorage.read(key: _passwordField);
     try {
       _appPassword = await pushSecureStorage.read(key: _appPasswordField);
+      _appPasswordTalk = await pushSecureStorage.read(
+        key: _appPasswordTalkField,
+      );
     } on Object {
       _appPassword = null;
+      _appPasswordTalk = null;
     }
     if (!_populated.isCompleted) _populated.complete();
   }
@@ -149,6 +190,22 @@ class AccountData {
     return 'Basic ${base64Encode(utf8.encode('$_username:$secret'))}';
   }
 
+  /// Basic-auth header using the Talk app password — authenticates the
+  /// apptype=talk push registration (and its unregister). Throws when the
+  /// talk password has not been minted yet; callers treat that as a failed
+  /// talk registration and retry on the next start.
+  String getTalkBasicAuthHeader() {
+    if (!isPopulated()) {
+      throw Exception(
+        'AccountData (e.g. username or password) is not initialized!',
+      );
+    }
+    if (!hasAppPasswordTalk()) {
+      throw StateError('Talk app password not available yet');
+    }
+    return 'Basic ${base64Encode(utf8.encode('$_username:$_appPasswordTalk'))}';
+  }
+
   /// Basic-auth header that always uses the real password. Needed exactly once,
   /// to mint the app password via `core/getapppassword` (an app password cannot
   /// mint another).

lib/notification/notification_service.dart

@@ -15,8 +15,11 @@ class NotificationService {
       FlutterLocalNotificationsPlugin();
 
   Future<void> initializeNotifications() async {
+    // Dedicated monochrome status-bar icon: launcher mipmaps are unusable as
+    // small icons because Android renders only their alpha silhouette (a
+    // solid circle in the status bar).
     const androidSettings = AndroidInitializationSettings(
-      '@mipmap/ic_launcher',
+      '@drawable/ic_stat_notification',
     );
 
     // iOS Talk category mirrors the Android inline reply + mark-as-read actions

lib/notification/notification_tasks.dart

@@ -6,6 +6,7 @@ import 'package:flutter/services.dart';
 import 'package:flutter_app_badge/flutter_app_badge.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 
+import '../push/chat_thread_store.dart';
 import '../routing/app_routes.dart';
 import '../state/app/modules/chat_list/bloc/chat_list_bloc.dart';
 import 'notification_service.dart';
@@ -25,9 +26,9 @@ class NotificationTasks {
     }
   }
 
-  /// Per-chat tag scheme. MUST match the Notify backend, which sets this
-  /// value on `AndroidNotification.setTag` AND `apns-collapse-id`.
-  static String chatTag(String chatToken) => 'talk_$chatToken';
+  /// Per-chat tag scheme — canonical definition lives beside the stacked
+  /// notification id in chat_thread_store.dart.
+  static String chatTag(String chatToken) => chatNotificationTag(chatToken);
 
   /// Removes tray notifications belonging to [chatToken]. Eraser handles
   /// iOS (where the plugin's `getActiveNotifications` returns null ids
@@ -54,6 +55,13 @@ class NotificationTasks {
     } on Object catch (e) {
       log('Active-notification sweep failed: $e');
     }
+    // Drop the stacked-notification history too — otherwise the next push
+    // would resurrect all already-read messages in the new notification.
+    try {
+      await ChatThreadStore().clearChat(chatToken);
+    } on Object catch (e) {
+      log('Chat thread cleanup failed: $e');
+    }
   }
 
   /// Refreshes the chat list. Deliberately does NOT touch [ChatBloc] —

lib/push/chat_thread_store.dart

@@ -0,0 +1,210 @@
+import 'dart:convert';
+
+import 'package:localstore/localstore.dart';
+
+/// Maximum messages kept per chat thread — enough for a messenger-style
+/// notification, small enough to stay cheap in the background isolate.
+const int kChatThreadCap = 15;
+
+/// Canonical per-chat notification tag (kept in sync with
+/// `NotificationTasks.chatTag`, which delegates here).
+String chatNotificationTag(String chatToken) => 'talk_$chatToken';
+
+/// Deterministic non-negative 31-bit notification id per chat, so every
+/// message of the same conversation updates ONE stacked notification instead
+/// of adding a new card per push.
+int stableChatNotificationId(String chatToken) {
+  var hash = 0;
+  for (final unit in chatToken.codeUnits) {
+    hash = (hash * 31 + unit) & 0x7fffffff;
+  }
+  return hash;
+}
+
+/// One message inside a chat's notification history.
+class ThreadMessage {
+  final int nid;
+  final String sender;
+  final String text;
+  final int timestampMs;
+
+  /// Room name parsed from a group-chat subject (`<sender> in <room>`);
+  /// null for 1:1 chats and for history entries written before this field
+  /// existed (tolerated on read — they simply carry no room information).
+  final String? roomName;
+
+  const ThreadMessage({
+    required this.nid,
+    required this.sender,
+    required this.text,
+    required this.timestampMs,
+    this.roomName,
+  });
+
+  Map<String, dynamic> toJson() => {
+    'nid': nid,
+    'sender': sender,
+    'text': text,
+    'timestampMs': timestampMs,
+    'roomName': ?roomName,
+  };
+
+  factory ThreadMessage.fromJson(Map<String, dynamic> json) => ThreadMessage(
+    nid: (json['nid'] as num).toInt(),
+    sender: json['sender'] as String? ?? '',
+    text: json['text'] as String? ?? '',
+    timestampMs: (json['timestampMs'] as num?)?.toInt() ?? 0,
+    roomName: json['roomName'] as String?,
+  );
+}
+
+/// Appends [message] to [messages], replacing an entry with the same nid
+/// (redelivered push) and capping the history at [cap] (oldest dropped).
+/// Pure so the stacking behavior is unit-testable.
+List<ThreadMessage> appendThreadMessage(
+  List<ThreadMessage> messages,
+  ThreadMessage message, {
+  int cap = kChatThreadCap,
+}) {
+  final result = [...messages.where((m) => m.nid != message.nid), message];
+  return result.length > cap ? result.sublist(result.length - cap) : result;
+}
+
+/// Removes the message with [nid]; the caller cancels the notification when
+/// the returned list is empty and re-renders it silently otherwise.
+List<ThreadMessage> removeThreadNid(List<ThreadMessage> messages, int nid) =>
+    messages.where((m) => m.nid != nid).toList();
+
+/// History for the next notification after [message] arrives, given whether
+/// the chat's previous notification is still on screen ([isActive]):
+///
+/// - `true` → the user hasn't dismissed/read it, so [message] STACKS onto the
+///   existing history.
+/// - `false` → the notification is gone (swiped away or the chat was read
+///   without our cleanup running), so the thread RESTARTS with only [message].
+/// - `null` → the active-notification probe failed or isn't supported; keep
+///   stacking defensively — degraded stacking never loses a message.
+///
+/// Android provides no reliable "notification dismissed" callback, so the
+/// visible-state probe at append time is the substitute.
+List<ThreadMessage> threadAfterIncoming(
+  List<ThreadMessage> existing,
+  ThreadMessage message,
+  bool? isActive, {
+  int cap = kChatThreadCap,
+}) {
+  final base = isActive == false ? const <ThreadMessage>[] : existing;
+  return appendThreadMessage(base, message, cap: cap);
+}
+
+/// MessagingStyle header per Android convention: a 1:1 chat gets NO
+/// `conversationTitle` — the system then shows the person once as the header
+/// and plain texts per line; setting a title would repeat the name on every
+/// row. Groups get the ROOM NAME as title (parsed from the subject) plus
+/// per-line sender names; when no room name is known, >1 distinct sender
+/// still marks the thread as group with the last sender as title fallback.
+({String? conversationTitle, bool groupConversation}) conversationHeader(
+  List<ThreadMessage> messages,
+) {
+  final roomName = messages
+      .lastWhere(
+        (m) => m.roomName?.isNotEmpty ?? false,
+        orElse: () =>
+            const ThreadMessage(nid: 0, sender: '', text: '', timestampMs: 0),
+      )
+      .roomName;
+  if (roomName != null && roomName.isNotEmpty) {
+    return (conversationTitle: roomName, groupConversation: true);
+  }
+  final distinctSenders = messages.map((m) => m.sender).toSet().length;
+  if (distinctSenders <= 1) {
+    return (conversationTitle: null, groupConversation: false);
+  }
+  return (conversationTitle: messages.last.sender, groupConversation: true);
+}
+
+/// Persists the per-chat message history via [Localstore] so both the
+/// foreground and the FCM background isolate build the same stacked
+/// notification. Complements [NidStore], which keeps the nid → chat mapping
+/// needed to resolve delete-pushes.
+class ChatThreadStore {
+  static const _collection = 'push_chat_threads';
+
+  final Localstore _db;
+
+  ChatThreadStore({Localstore? db}) : _db = db ?? Localstore.instance;
+
+  /// Localstore doc ids become file names — tokens are normally URL-safe and
+  /// used verbatim, anything else is base64url-encoded.
+  static String docIdForToken(String chatToken) =>
+      RegExp(r'^[A-Za-z0-9_-]+$').hasMatch(chatToken)
+      ? chatToken
+      : base64Url.encode(utf8.encode(chatToken)).replaceAll('=', '');
+
+  Future<List<ThreadMessage>> messages(String chatToken) async {
+    final data = await _doc(chatToken).get();
+    final raw = data?['messages'];
+    if (raw is! List) return const [];
+    return raw
+        .whereType<Map<String, dynamic>>()
+        .map(ThreadMessage.fromJson)
+        .toList();
+  }
+
+  /// Appends [message] and returns the updated (capped) history.
+  Future<List<ThreadMessage>> append(
+    String chatToken,
+    ThreadMessage message,
+  ) async {
+    final updated = appendThreadMessage(await messages(chatToken), message);
+    await _write(chatToken, updated);
+    return updated;
+  }
+
+  /// Appends [message], but restarts the thread first when the chat's previous
+  /// notification is no longer active ([isActive] == false — dismissed/read).
+  /// See [threadAfterIncoming] for the tri-state semantics.
+  Future<List<ThreadMessage>> appendConsideringActive(
+    String chatToken,
+    ThreadMessage message,
+    bool? isActive,
+  ) async {
+    final updated = threadAfterIncoming(
+      await messages(chatToken),
+      message,
+      isActive,
+    );
+    await _write(chatToken, updated);
+    return updated;
+  }
+
+  /// Removes the message with [nid] and returns the remaining history.
+  Future<List<ThreadMessage>> removeNid(String chatToken, int nid) async {
+    final remaining = removeThreadNid(await messages(chatToken), nid);
+    if (remaining.isEmpty) {
+      await clearChat(chatToken);
+    } else {
+      await _write(chatToken, remaining);
+    }
+    return remaining;
+  }
+
+  Future<void> clearChat(String chatToken) => _doc(chatToken).delete();
+
+  Future<void> clearAll() async {
+    final docs = await _db.collection(_collection).get();
+    if (docs == null) return;
+    for (final id in docs.keys) {
+      // Localstore keys are full document paths (/push_chat_threads/<id>).
+      await _db.collection(_collection).doc(id.split('/').last).delete();
+    }
+  }
+
+  DocumentRef _doc(String chatToken) =>
+      _db.collection(_collection).doc(docIdForToken(chatToken));
+
+  Future<void> _write(String chatToken, List<ThreadMessage> messages) =>
+      _doc(chatToken).set({
+        'messages': [for (final m in messages) m.toJson()],
+      });
+}

lib/push/nextcloud_push_api.dart

@@ -39,17 +39,24 @@ class NextcloudPushApi {
 
   NextcloudPushApi({http.Client? client}) : _client = client ?? http.Client();
 
-  /// Registers (or refreshes) this device. [devicePublicKeyPem] must be the
-  /// 64-column SPKI PEM. [proxyServer] is the MarianumConnect push-proxy base
-  /// URL (with trailing slash).
+  /// Registers (or refreshes) a device subscription. [devicePublicKeyPem] must
+  /// be the 64-column SPKI PEM. [proxyServer] is the MarianumConnect push-proxy
+  /// base URL (with trailing slash).
+  ///
+  /// [authorizationHeader] overrides the Basic auth (e.g. the Talk app
+  /// password — NC binds the subscription to the authenticated session token).
+  /// [userAgent] overrides the UA; a Talk-pattern UA makes NC classify the
+  /// subscription as apptype `talk` and route Talk pushes to it.
   Future<NextcloudPushRegistration> register({
     required String pushTokenHash,
     required String devicePublicKeyPem,
     required String proxyServer,
+    String? authorizationHeader,
+    String? userAgent,
   }) async {
     final response = await _client.post(
       NextcloudOcs.uri(_path),
-      headers: NextcloudOcs.headers(),
+      headers: _headers(authorizationHeader, userAgent),
       body: {
         'pushTokenHash': pushTokenHash,
         'devicePublicKey': devicePublicKeyPem,
@@ -76,13 +83,24 @@ class NextcloudPushApi {
     );
   }
 
-  /// Unregisters this device from Nextcloud push. Returns true when the server
-  /// responded 202, meaning the proxy subscription should also be removed.
-  Future<bool> unregister() async {
+  /// Unregisters one device subscription — the DELETE is per session token, so
+  /// each registration is removed with its own app password via
+  /// [authorizationHeader]. Returns true when the server responded 202,
+  /// meaning the proxy subscription should also be removed.
+  Future<bool> unregister({String? authorizationHeader}) async {
     final response = await _client.delete(
       NextcloudOcs.uri(_path),
-      headers: NextcloudOcs.headers(),
+      headers: _headers(authorizationHeader, null),
     );
     return response.statusCode == 202;
   }
+
+  Map<String, String> _headers(
+    String? authorizationHeader,
+    String? userAgent,
+  ) => {
+    ...NextcloudOcs.headers(),
+    'Authorization': ?authorizationHeader,
+    'User-Agent': ?userAgent,
+  };
 }

lib/push/push_actions.dart

@@ -1,12 +1,17 @@
+import 'dart:async';
 import 'dart:convert';
 import 'dart:developer';
+import 'dart:ui';
 
 import 'package:flutter_local_notifications/flutter_local_notifications.dart';
 import 'package:http/http.dart' as http;
 
 import '../api/marianumcloud/nextcloud_ocs.dart';
 import '../model/account_data.dart';
+import '../notification/notification_service.dart';
+import 'chat_thread_store.dart';
 import 'nid_store.dart';
+import 'push_renderer.dart';
 
 /// Notification action identifiers shared between the renderer (which attaches
 /// the actions) and the response handlers (which dispatch them).
@@ -24,60 +29,147 @@ class PushActions {
   static Future<void> handleBackgroundResponse(
     NotificationResponse response,
   ) async {
+    // The FLN action isolate starts WITHOUT main(): unlike the FCM background
+    // isolate, plugins are not registered automatically there. Without this,
+    // AccountData's secure-storage/prefs reads throw or never complete → no
+    // auth header, the Talk POST never happens and the RemoteInput spinner
+    // runs forever.
+    DartPluginRegistrant.ensureInitialized();
+
     final chatToken = _chatTokenFrom(response.payload);
     if (chatToken == null) return;
     switch (response.actionId) {
       case kTalkReplyActionId:
         final text = response.input?.trim();
-        if (text != null && text.isNotEmpty) {
-          await sendReply(chatToken, text);
+        final sent = text != null && text.isNotEmpty
+            ? await sendReply(chatToken, text)
+            : false;
+        if (sent) {
+          // The user has evidently seen the chat — set the read marker like
+          // the mark-read action does.
+          await markRead(chatToken);
         }
-        await markRead(chatToken);
+        await finishReply(chatToken: chatToken, sent: sent);
+        _cleanupNidEntry(response);
         break;
       case kTalkMarkReadActionId:
         await markRead(chatToken);
-        await _cancelForToken(response);
+        await _cleanupChat(chatToken);
+        _cleanupNidEntry(response);
         break;
       default:
         break;
     }
   }
 
-  static Future<void> sendReply(String chatToken, String message) async {
-    await _ocsPost(
-      'apps/spreed/api/v1/chat/$chatToken',
-      body: {'message': message},
-    );
+  /// Ends the reply interaction: Android keeps the RemoteInput spinner alive
+  /// until the notification is UPDATED or REMOVED. Success removes the whole
+  /// notification (history cleared + cancel — the chat is read); failure
+  /// re-renders the unchanged thread silently so the spinner stops (the error
+  /// itself is only loggable on notification level). Injectable seams so
+  /// tests can observe the flow without platform channels.
+  static Future<void> finishReply({
+    required String chatToken,
+    required bool sent,
+    Future<void> Function(String chatToken)? cleanupChat,
+    Future<List<ThreadMessage>> Function(String chatToken)? loadThread,
+    Future<void> Function(String chatToken, List<ThreadMessage> messages)?
+    renderSilent,
+    Future<void> Function(String chatToken)? cancelNotification,
+  }) async {
+    cleanupChat ??= _cleanupChat;
+    loadThread ??= (token) => ChatThreadStore().messages(token);
+    renderSilent ??= (token, messages) =>
+        PushRenderer().renderTalkThread(token, messages, alert: false);
+    cancelNotification ??= _cancelChatNotification;
+
+    if (sent) {
+      await cleanupChat(chatToken);
+      return;
+    }
+    final messages = await loadThread(chatToken);
+    if (messages.isEmpty) {
+      // Nothing to re-render (history cleared meanwhile) — cancel instead so
+      // the spinner cannot survive.
+      await cancelNotification(chatToken);
+      return;
+    }
+    await renderSilent(chatToken, messages);
   }
 
-  static Future<void> markRead(String chatToken) async {
-    await _ocsPost('apps/spreed/api/v1/chat/$chatToken/read');
-  }
+  /// Sends the inline reply. Success = any 2xx (the Talk chat POST answers
+  /// 201 Created). Path/body match the app's working send path
+  /// (`SendMessage`: `v1/chat/{token}`, form field `message`).
+  static Future<bool> sendReply(String chatToken, String message) => _ocsPost(
+    'apps/spreed/api/v1/chat/$chatToken',
+    body: {'message': message},
+  );
 
-  static Future<void> _ocsPost(String path, {Map<String, String>? body}) async {
+  static Future<bool> markRead(String chatToken) =>
+      _ocsPost('apps/spreed/api/v1/chat/$chatToken/read');
+
+  static Future<bool> _ocsPost(String path, {Map<String, String>? body}) async {
     try {
-      await AccountData().waitForPopulation();
+      // Bounded: a hanging population (e.g. keystore issue) must fail the
+      // action instead of leaving the notification spinner running forever.
+      await AccountData().waitForPopulation().timeout(
+        const Duration(seconds: 10),
+      );
       final response = await http.post(
         NextcloudOcs.uri(path),
         headers: NextcloudOcs.headers(),
         body: body,
       );
-      if (response.statusCode < 200 || response.statusCode >= 300) {
+      final ok = response.statusCode >= 200 && response.statusCode < 300;
+      if (ok) {
         log('Push action $path -> HTTP ${response.statusCode}');
+      } else {
+        final preview = response.body.replaceAll(RegExp(r'\s+'), ' ').trim();
+        log(
+          'Push action $path -> HTTP ${response.statusCode} '
+          'body=${preview.length > 300 ? '${preview.substring(0, 300)}…' : preview}',
+        );
       }
+      return ok;
     } on Object catch (e) {
       log('Push action $path failed: $e');
+      return false;
     }
   }
 
-  static Future<void> _cancelForToken(NotificationResponse response) async {
+  /// Mark-read cleanup: drop the stacked history (so the next push starts
+  /// fresh) and cancel the chat's notification.
+  static Future<void> _cleanupChat(String chatToken) async {
+    try {
+      await ChatThreadStore().clearChat(chatToken);
+    } on Object catch (e) {
+      log('Push action thread cleanup failed: $e');
+    }
+    await _cancelChatNotification(chatToken);
+  }
+
+  static Future<void> _cancelChatNotification(String chatToken) async {
+    try {
+      await NotificationService().flutterLocalNotificationsPlugin.cancel(
+        id: stableChatNotificationId(chatToken),
+        tag: chatNotificationTag(chatToken),
+      );
+    } on Object catch (e) {
+      log('Push action cancel failed: $e');
+    }
+  }
+
+  static void _cleanupNidEntry(NotificationResponse response) {
     final nid = _nidFrom(response.payload);
     if (nid == null) return;
-    try {
-      await NidStore().delete(nid);
-    } on Object catch (e) {
-      log('Push action nid cleanup failed: $e');
-    }
+    unawaited(
+      NidStore()
+          .delete(nid)
+          .then(
+            (_) {},
+            onError: (Object e) => log('Push action nid cleanup failed: $e'),
+          ),
+    );
   }
 
   static String? _chatTokenFrom(String? payload) =>

lib/push/push_avatar.dart

@@ -0,0 +1,245 @@
+import 'dart:async';
+import 'dart:convert';
+import 'dart:developer';
+import 'dart:io';
+import 'dart:typed_data';
+import 'dart:ui' as ui;
+
+import 'package:http/http.dart' as http;
+import 'package:path_provider/path_provider.dart';
+
+import '../api/marianumcloud/nextcloud_ocs.dart';
+
+/// Result of an avatar lookup at render time: [icon] when bytes are available
+/// within the fetch budget, otherwise [late] carries the still-running fetch
+/// so the caller can re-render once (silently) when it eventually delivers.
+typedef AvatarIconLookup = ({Uint8List? icon, Future<Uint8List?>? late});
+
+/// Masks avatar [bytes] into a circular PNG on a square canvas (center-cover
+/// crop). Devices do NOT reliably mask Person icons themselves, so the round
+/// shape is baked into the bitmap. Runs on `dart:ui`, which is available in
+/// engine-backed background isolates (the FCM handler isolate) — no
+/// BuildContext involved. Returns null when decoding fails; callers fall back
+/// to the raw bytes.
+Future<Uint8List?> maskAvatarCircular(Uint8List bytes) async {
+  try {
+    final codec = await ui.instantiateImageCodec(bytes);
+    final frame = await codec.getNextFrame();
+    final image = frame.image;
+    final size = image.width < image.height ? image.width : image.height;
+    final src = ui.Rect.fromLTWH(
+      (image.width - size) / 2,
+      (image.height - size) / 2,
+      size.toDouble(),
+      size.toDouble(),
+    );
+    final dst = ui.Rect.fromLTWH(0, 0, size.toDouble(), size.toDouble());
+
+    final recorder = ui.PictureRecorder();
+    final canvas = ui.Canvas(recorder);
+    canvas.clipPath(ui.Path()..addOval(dst));
+    canvas.drawImageRect(image, src, dst, ui.Paint()..isAntiAlias = true);
+    final masked = await recorder.endRecording().toImage(size, size);
+    final data = await masked.toByteData(format: ui.ImageByteFormat.png);
+    image.dispose();
+    masked.dispose();
+    return data?.buffer.asUint8List();
+  } on Object catch (e) {
+    log('Push avatar: circular mask failed: $e');
+    return null;
+  }
+}
+
+/// Loads conversation avatars for Talk push notifications.
+///
+/// Uses the same Spreed endpoint as the in-app `UserAvatar` widget
+/// (`room/{token}/avatar`, no query parameters — for 1:1 chats this is the
+/// other person's picture), but with its own disk cache of PRE-MASKED round
+/// PNGs: the widget cache is an in-memory LRU that is empty in the FCM
+/// background isolate, and masking must not be recomputed per push. Every
+/// failure path returns null so a missing avatar can never delay or drop a
+/// notification beyond [fetchTimeout].
+class PushAvatarStore {
+  /// Cached files older than this are treated as stale and pruned.
+  static const Duration maxAge = Duration(days: 14);
+
+  static const Duration _defaultFetchTimeout = Duration(seconds: 4);
+
+  // Versioned: `push_avatars` (raw, unmasked) was used before masking landed —
+  // reusing it would surface square icons from old cache entries.
+  static const _subDirectory = 'push_avatars_masked';
+
+  /// One shared fetch per token and isolate: the bounded render-time lookup
+  /// and the late re-render both await the SAME future, and concurrent pushes
+  /// don't stampede the endpoint.
+  static final Map<String, Future<Uint8List?>> _inflight = {};
+
+  final Future<Directory> Function() _cacheDirProvider;
+
+  /// Fetches the raw avatar response for a chat token. Injectable so tests
+  /// never touch the network or the account/endpoint singletons (the default
+  /// builds auth headers from them).
+  final Future<http.Response> Function(String chatToken) _fetch;
+  final Duration fetchTimeout;
+
+  PushAvatarStore({
+    Future<Directory> Function()? cacheDirProvider,
+    Future<http.Response> Function(String chatToken)? fetch,
+    this.fetchTimeout = _defaultFetchTimeout,
+  }) : _cacheDirProvider = cacheDirProvider ?? _defaultCacheDir,
+       _fetch = fetch ?? _defaultFetch;
+
+  static Future<Directory> _defaultCacheDir() async {
+    final base = await getApplicationCacheDirectory();
+    return Directory('${base.path}/$_subDirectory');
+  }
+
+  static Future<http.Response> _defaultFetch(String chatToken) => http.get(
+    NextcloudOcs.uri('apps/spreed/api/v1/room/$chatToken/avatar'),
+    headers: {
+      ...NextcloudOcs.headers(),
+      'Accept': 'image/png,image/jpeg,image/webp',
+    },
+  );
+
+  /// File-safe cache name for a chat token. Tokens are normally URL-safe
+  /// already and used verbatim; anything else is base64url-encoded so exotic
+  /// ids can never escape the cache directory.
+  static String fileNameForToken(String token) =>
+      RegExp(r'^[A-Za-z0-9_-]+$').hasMatch(token)
+      ? token
+      : base64Url.encode(utf8.encode(token)).replaceAll('=', '');
+
+  /// Whether a cache file written at [modified] is still fresh at [now].
+  static bool isFresh(DateTime modified, DateTime now) =>
+      now.difference(modified) <= maxAge;
+
+  /// Spreed answers with an SVG placeholder (initials/icon) when a chat has
+  /// no real picture — useless for a notification bitmap, so it is skipped.
+  static bool looksLikeSvg(Uint8List bytes) {
+    final head = utf8
+        .decode(
+          bytes.sublist(0, bytes.length < 256 ? bytes.length : 256),
+          allowMalformed: true,
+        )
+        .trimLeft();
+    return head.startsWith('<?xml') || head.startsWith('<svg');
+  }
+
+  /// Returns the (round-masked) conversation avatar for [chatToken]. Order:
+  /// fresh disk cache → shared network fetch bounded by [fetchTimeout] →
+  /// stale disk cache. On timeout the fetch keeps running and is returned as
+  /// [AvatarIconLookup.late] so the caller can re-render once it delivers.
+  Future<AvatarIconLookup> roomAvatarIcon(String chatToken) async {
+    try {
+      final file = await _fileFor(chatToken);
+      final fresh = await _readCache(file, allowStale: false);
+      if (fresh != null) return (icon: fresh, late: null);
+
+      final fetch = _inflight.putIfAbsent(chatToken, () {
+        final future = _fetchProcessAndCache(chatToken, file);
+        future.whenComplete(() {
+          if (identical(_inflight[chatToken], future)) {
+            _inflight.remove(chatToken);
+          }
+        });
+        return future;
+      });
+
+      try {
+        final fetched = await fetch.timeout(fetchTimeout);
+        if (fetched != null) return (icon: fetched, late: null);
+        // Definitive miss (no picture / error) — an outdated icon beats none.
+        return (icon: await _readCache(file, allowStale: true), late: null);
+      } on TimeoutException {
+        // Fetch continues in the background; hand it to the caller for the
+        // one-time silent re-render.
+        return (icon: await _readCache(file, allowStale: true), late: fetch);
+      }
+    } on Object catch (e) {
+      log('Push avatar $chatToken: lookup failed: $e');
+      return (icon: null, late: null);
+    }
+  }
+
+  /// Drops the cached avatar for [chatToken] — called when the app knows the
+  /// picture changed (avatar upload/removal in chat settings).
+  static Future<void> evict(String chatToken) async {
+    try {
+      final dir = await _defaultCacheDir();
+      final file = File('${dir.path}/${fileNameForToken(chatToken)}');
+      if (file.existsSync()) await file.delete();
+    } on Object {
+      // best effort — the 14-day max age catches it eventually
+    }
+  }
+
+  Future<File> _fileFor(String chatToken) async {
+    final dir = await _cacheDirProvider();
+    await dir.create(recursive: true);
+    return File('${dir.path}/${fileNameForToken(chatToken)}');
+  }
+
+  Future<Uint8List?> _readCache(File file, {required bool allowStale}) async {
+    try {
+      if (!file.existsSync()) return null;
+      if (!allowStale && !isFresh(file.lastModifiedSync(), DateTime.now())) {
+        return null;
+      }
+      final bytes = await file.readAsBytes();
+      return bytes.isEmpty ? null : bytes;
+    } on Object {
+      return null;
+    }
+  }
+
+  /// Full pipeline: fetch (with outcome diagnostics) → circular mask (raw
+  /// fallback when masking fails) → write processed cache. Never throws.
+  Future<Uint8List?> _fetchProcessAndCache(String chatToken, File file) async {
+    try {
+      final raw = await _fetchAvatar(chatToken);
+      if (raw == null) return null;
+      final icon = await maskAvatarCircular(raw) ?? raw;
+      await file.writeAsBytes(icon, flush: true);
+      unawaited(_prune(file.parent));
+      return icon;
+    } on Object catch (e) {
+      log('Push avatar $chatToken: fetch/process failed: $e');
+      return null;
+    }
+  }
+
+  Future<Uint8List?> _fetchAvatar(String chatToken) async {
+    final response = await _fetch(chatToken);
+    final contentType = response.headers['content-type']?.toLowerCase() ?? '';
+    final bytes = response.bodyBytes;
+    final svgRejected =
+        response.statusCode == 200 &&
+        bytes.isNotEmpty &&
+        (contentType.contains('svg') || looksLikeSvg(bytes));
+    // Diagnostics: makes "no icon" cases attributable (status vs. svg
+    // placeholder vs. empty body) without a debugger on the device.
+    log(
+      'Push avatar $chatToken: HTTP ${response.statusCode} '
+      'type=$contentType bytes=${bytes.length} svgRejected=$svgRejected',
+    );
+    if (response.statusCode != 200 || bytes.isEmpty || svgRejected) return null;
+    return bytes;
+  }
+
+  /// Deletes cache files past [maxAge]. Fire-and-forget after a successful
+  /// write — the directory stays small (one file per recently active chat).
+  Future<void> _prune(Directory dir) async {
+    try {
+      final now = DateTime.now();
+      await for (final entry in dir.list()) {
+        if (entry is! File) continue;
+        if (!isFresh(entry.lastModifiedSync(), now)) {
+          await entry.delete();
+        }
+      }
+    } on Object {
+      // best effort
+    }
+  }
+}

lib/push/push_keypair.dart

@@ -44,7 +44,7 @@ class PushKeypair {
   final FlutterSecureStorageLike _storage;
 
   const PushKeypair({FlutterSecureStorageLike? storage})
-    : _storage = storage ?? const _DefaultStorage();
+    : _storage = storage ?? const PushSecureStorage();
 
   /// Returns the stored keypair PEMs, generating and persisting a fresh keypair
   /// on first use. Generation is offloaded to an isolate because RSA-2048 key
@@ -79,27 +79,3 @@ class PushKeypair {
     return PushKeypairPems(privateKeyPem: priv, publicKeyPem: pub);
   }
 }
-
-/// Minimal storage contract so tests can inject an in-memory fake instead of
-/// touching the platform keystore.
-abstract class FlutterSecureStorageLike {
-  Future<String?> read({required String key});
-  Future<void> write({required String key, required String? value});
-  Future<void> delete({required String key});
-}
-
-class _DefaultStorage implements FlutterSecureStorageLike {
-  const _DefaultStorage();
-
-  @override
-  Future<String?> read({required String key}) =>
-      pushSecureStorage.read(key: key);
-
-  @override
-  Future<void> write({required String key, required String? value}) =>
-      pushSecureStorage.write(key: key, value: value);
-
-  @override
-  Future<void> delete({required String key}) =>
-      pushSecureStorage.delete(key: key);
-}

lib/push/push_message_handler.dart

@@ -4,6 +4,7 @@ import 'package:crypton/crypton.dart';
 import 'package:firebase_messaging/firebase_messaging.dart';
 
 import '../notification/notification_service.dart';
+import 'chat_thread_store.dart';
 import 'nid_store.dart';
 import 'push_decryptor.dart';
 import 'push_keypair.dart';
@@ -34,6 +35,17 @@ PushKind classifyPush(Map<String, dynamic> data) {
   return PushKind.unknown;
 }
 
+/// FCM background isolate entry point. Must be a TOP-LEVEL function with the
+/// entry-point pragma: AOT builds cannot invoke static class members from
+/// native code unless the class itself is annotated too (DartVM error
+/// "must be annotated"), so a plain function is the reliable form.
+@pragma('vm:entry-point')
+Future<void> pushOnBackgroundMessage(RemoteMessage message) async {
+  await NotificationService().initializeNotifications();
+  await PushRenderer.ensureChannels();
+  await PushMessageHandler().handle(message);
+}
+
 /// Verifies, decrypts, and renders incoming push messages. Delete-pushes cancel
 /// the matching tray notification via [NidStore]. Works both in the FCM
 /// background isolate and the foreground.
@@ -42,25 +54,19 @@ class PushMessageHandler {
   final PushRegistrationStore _registrationStore;
   final PushRenderer _renderer;
   final NidStore _nidStore;
+  final ChatThreadStore _threadStore;
 
   PushMessageHandler({
     PushKeypair? keypair,
     PushRegistrationStore? registrationStore,
     PushRenderer? renderer,
     NidStore? nidStore,
+    ChatThreadStore? threadStore,
   }) : _keypair = keypair ?? const PushKeypair(),
        _registrationStore = registrationStore ?? const PushRegistrationStore(),
        _renderer = renderer ?? PushRenderer(),
-       _nidStore = nidStore ?? NidStore();
-
-  /// Background isolate entry point registered with
-  /// `FirebaseMessaging.onBackgroundMessage`.
-  @pragma('vm:entry-point')
-  static Future<void> onBackgroundMessage(RemoteMessage message) async {
-    await NotificationService().initializeNotifications();
-    await PushRenderer.ensureChannels();
-    await PushMessageHandler().handle(message);
-  }
+       _nidStore = nidStore ?? NidStore(),
+       _threadStore = threadStore ?? ChatThreadStore();
 
   /// Processes [message]. In the foreground, pass [foreground] true and
   /// [openChatToken] so a message for the currently open chat is suppressed
@@ -157,6 +163,7 @@ class PushMessageHandler {
         await _cancel(entry);
       }
       await _nidStore.clear();
+      await _threadStore.clearAll();
       return;
     }
     final nids = <int>[
@@ -165,7 +172,20 @@ class PushMessageHandler {
     ];
     for (final nid in nids) {
       final entry = await _nidStore.get(nid);
-      if (entry != null) await _cancel(entry);
+      final chatToken = entry?.chatToken;
+      if (chatToken != null && chatToken.isNotEmpty) {
+        // Stacked chat notification: drop only this message from the thread.
+        // Remaining messages re-render WITHOUT alerting again; the last one
+        // going away cancels the whole card.
+        final remaining = await _threadStore.removeNid(chatToken, nid);
+        if (remaining.isEmpty) {
+          await _cancel(entry!);
+        } else {
+          await _renderer.renderTalkThread(chatToken, remaining, alert: false);
+        }
+      } else if (entry != null) {
+        await _cancel(entry);
+      }
       await _nidStore.delete(nid);
     }
   }

lib/push/push_registration.dart

@@ -15,11 +15,26 @@ import '../model/endpoint_data.dart';
 import 'nextcloud_push_api.dart';
 import 'push_keypair.dart';
 import 'push_registration_store.dart';
+import 'push_registration_type.dart';
 
 /// Orchestrates the full push-v2 registration lifecycle:
 /// Nextcloud device registration → MarianumConnect proxy registration, plus
 /// unregister and token-refresh handling.
+///
+/// Every device maintains TWO Nextcloud registrations (see
+/// [PushRegistrationType]) sharing one keypair: a `general` one and a
+/// Talk-classified one, because NC routes Talk pushes only to apptype=talk
+/// subscriptions once the user has any (e.g. the official Talk app).
 class PushRegistration {
+  /// User agents matching nextcloud/server `IRequest` Talk patterns
+  /// (`USER_AGENT_TALK_ANDROID = '/^Mozilla\/5\.0 \(Android\) Nextcloud\-Talk
+  /// v([^ ]*).*$/'`, `USER_AGENT_TALK_IOS = '/^Mozilla\/5\.0 \(iOS\)
+  /// Nextcloud\-Talk v([^ ]*).*$/'`). Sent only on the talk registration so
+  /// NC stores it with apptype `talk`.
+  static const String talkUserAgentAndroid =
+      'Mozilla/5.0 (Android) Nextcloud-Talk v1.0.0 MarianumMobile';
+  static const String talkUserAgentIos =
+      'Mozilla/5.0 (iOS) Nextcloud-Talk v1.0.0 MarianumMobile';
   final PushKeypair _keypair;
   final PushRegistrationStore _store;
   final NextcloudPushApi _nextcloud;
@@ -34,13 +49,18 @@ class PushRegistration {
 
   String get _platform => Platform.isIOS ? 'ios' : 'android';
 
+  String get _talkUserAgent =>
+      Platform.isIOS ? talkUserAgentIos : talkUserAgentAndroid;
+
   /// Derives the push-proxy base URL from the active MarianumConnect endpoint,
   /// so a beta/dev build registers against the matching proxy automatically.
-  String get _proxyServer => '${MarianumConnectEndpoint.current()}/push-proxy/';
+  /// Public so the push status view can compare it against the stored binding.
+  String get currentProxyServer =>
+      '${MarianumConnectEndpoint.current()}/push-proxy/';
 
   /// Nextcloud origin the registration targets (full origin, no trailing
   /// slash) — persisted alongside the registration to detect endpoint changes.
-  String get _ncBaseUrl => 'https://${EndpointData().nextcloud().full()}';
+  String get currentNcBaseUrl => 'https://${EndpointData().nextcloud().full()}';
 
   /// Ensures the Nextcloud app password exists (idempotent, best-effort). Push
   /// registration binds to it, so it must be obtained before registering.
@@ -54,28 +74,94 @@ class PushRegistration {
     }
   }
 
-  /// Registers this device end-to-end. No-op-safe: transport failures are
-  /// logged and swallowed so callers can fire-and-forget.
-  Future<void> register() async {
+  /// Ensures the second app password backing the Talk registration exists
+  /// (each `getapppassword` call with the real password mints a fresh one).
+  Future<void> ensureTalkAppPassword() async {
+    if (AccountData().hasAppPasswordTalk()) return;
     try {
-      final fcmToken = await FirebaseMessaging.instance.getToken();
-      if (fcmToken == null || fcmToken.isEmpty) {
-        log('Push: no FCM token, skipping registration');
-        return;
-      }
-      await ensureAppPassword();
-      await _persistNativeAuthContext();
+      final appPassword = await GetAppPassword().run();
+      await AccountData().setAppPasswordTalk(appPassword);
+    } on Object catch (e) {
+      log('Push: could not obtain talk app password (non-blocking): $e');
+    }
+  }
 
-      final proxyServer = _proxyServer;
-      final ncBaseUrl = _ncBaseUrl;
-      final pems = await _keypair.ensure();
+  /// Registers this device end-to-end: both Nextcloud registrations (general,
+  /// then talk) each followed by their MarianumConnect proxy registration.
+  /// Partial results are persisted per type — one failing registration never
+  /// blocks the other. Returns true only when BOTH succeeded. No-op-safe:
+  /// transport failures are logged and swallowed so callers can
+  /// fire-and-forget (and simply ignore the result).
+  Future<bool> register() async {
+    final String? fcmToken;
+    try {
+      fcmToken = await FirebaseMessaging.instance.getToken();
+    } on Object catch (e) {
+      log('Push: could not obtain FCM token: $e');
+      await _recordAttempts('Kein FCM-Token verfügbar');
+      return false;
+    }
+    if (fcmToken == null || fcmToken.isEmpty) {
+      log('Push: no FCM token, skipping registration');
+      await _recordAttempts('Kein FCM-Token verfügbar');
+      return false;
+    }
+
+    await ensureAppPassword();
+    await ensureTalkAppPassword();
+    await _persistNativeAuthContext();
+
+    final PushKeypairPems pems;
+    try {
+      pems = await _keypair.ensure();
+    } on Object catch (e) {
+      log('Push: keypair unavailable: $e');
+      await _recordAttempts(_shortError(e));
+      return false;
+    }
+
+    String? appVersion;
+    try {
+      appVersion = (await PackageInfo.fromPlatform()).version;
+    } on Object {
+      appVersion = null;
+    }
+
+    var allOk = true;
+    for (final type in PushRegistrationType.values) {
+      final ok = await _registerType(
+        type: type,
+        fcmToken: fcmToken,
+        pems: pems,
+        appVersion: appVersion,
+      );
+      allOk = allOk && ok;
+    }
+    return allOk;
+  }
+
+  Future<bool> _registerType({
+    required PushRegistrationType type,
+    required String fcmToken,
+    required PushKeypairPems pems,
+    required String? appVersion,
+  }) async {
+    try {
+      final proxyServer = currentProxyServer;
+      final ncBaseUrl = currentNcBaseUrl;
+      final isTalk = type == PushRegistrationType.talk;
       final registration = await _nextcloud.register(
-        pushTokenHash: generatePushTokenHash(fcmToken),
+        pushTokenHash: generatePushTokenHash(pushTokenVariant(fcmToken, type)),
         devicePublicKeyPem: pems.publicKeyPem,
         proxyServer: proxyServer,
+        authorizationHeader: isTalk
+            ? AccountData().getTalkBasicAuthHeader()
+            : null,
+        userAgent: isTalk ? _talkUserAgent : null,
       );
 
       await _store.save(
+        type: type,
         deviceIdentifier: registration.deviceIdentifier,
         serverPublicKeyPem: registration.publicKey,
         fcmToken: fcmToken,
@@ -83,27 +169,53 @@ class PushRegistration {
         ncBaseUrl: ncBaseUrl,
       );
 
-      String? appVersion;
-      try {
-        appVersion = (await PackageInfo.fromPlatform()).version;
-      } on Object {
-        appVersion = null;
-      }
-
       await PushDeviceRegister().run(
         deviceIdentifier: registration.deviceIdentifier,
         deviceIdentifierSignature: registration.signature,
         userPublicKey: registration.publicKey,
         pushToken: fcmToken,
         platform: _platform,
+        registrationType: type.wireName,
         appVersion: appVersion,
       );
-      log('Push: registered (created=${registration.created})');
+      log(
+        'Push: registered ${type.wireName} '
+        '(created=${registration.created})',
+      );
+      await _recordAttempt(type, null);
+      return true;
     } on Object catch (e) {
-      log('Push: registration failed: $e');
+      log('Push: ${type.wireName} registration failed: $e');
+      await _recordAttempt(type, _shortError(e));
+      return false;
     }
   }
 
+  /// Persists the attempt outcome for the push status view. Storage failures
+  /// must never mask the actual registration result.
+  Future<void> _recordAttempt(PushRegistrationType type, String? error) async {
+    try {
+      await _store.saveLastRegistrationAttempt(
+        type: type,
+        at: DateTime.now(),
+        error: error,
+      );
+    } on Object {
+      // ignore — the status view simply shows the previous attempt
+    }
+  }
+
+  Future<void> _recordAttempts(String? error) async {
+    for (final type in PushRegistrationType.values) {
+      await _recordAttempt(type, error);
+    }
+  }
+
+  static String _shortError(Object e) {
+    final text = e.toString();
+    return text.length > 300 ? '${text.substring(0, 300)}…' : text;
+  }
+
   /// Writes the username and Nextcloud base URL into the shared keychain so the
   /// native iOS Talk action handler can authenticate OCS calls without the
   /// Flutter engine. Best-effort — a failure here must not abort registration.
@@ -119,19 +231,28 @@ class PushRegistration {
     }
   }
 
-  /// Removes the subscription from Nextcloud and the proxy. Best-effort.
+  /// Removes both subscriptions from Nextcloud and the proxy. Best-effort —
+  /// each step is independent so one failure never blocks the rest.
   Future<void> unregister() async {
-    final deviceIdentifier = await _store.deviceIdentifier();
-    try {
-      await _nextcloud.unregister();
-    } on Object catch (e) {
-      log('Push: NC unregister failed: $e');
-    }
-    if (deviceIdentifier != null && deviceIdentifier.isNotEmpty) {
+    for (final type in PushRegistrationType.values) {
+      final deviceIdentifier = await _store.deviceIdentifier(type);
       try {
-        await PushDeviceUnregister().run(deviceIdentifier: deviceIdentifier);
+        // The DELETE removes the subscription bound to the authenticating
+        // session token — each registration with its own app password.
+        await _nextcloud.unregister(
+          authorizationHeader: type == PushRegistrationType.talk
+              ? AccountData().getTalkBasicAuthHeader()
+              : null,
+        );
       } on Object catch (e) {
-        log('Push: proxy unregister failed: $e');
+        log('Push: NC unregister (${type.wireName}) failed: $e');
+      }
+      if (deviceIdentifier != null && deviceIdentifier.isNotEmpty) {
+        try {
+          await PushDeviceUnregister().run(deviceIdentifier: deviceIdentifier);
+        } on Object catch (e) {
+          log('Push: proxy unregister (${type.wireName}) failed: $e');
+        }
       }
     }
     await _store.clear();
@@ -146,19 +267,24 @@ class PushRegistration {
     required String current,
   }) => registered != null && registered.isNotEmpty && registered != current;
 
-  /// True when an existing registration was made against a different
+  /// True when any existing registration was made against a different
   /// MarianumConnect proxy or Nextcloud base URL than the ones currently
   /// configured (dev-tools endpoint switch, live/beta/custom).
   Future<bool> needsEndpointReRegistration() async {
-    if (!await _store.isRegistered()) return false;
-    return endpointChanged(
-          registered: await _store.registeredProxyServer(),
-          current: _proxyServer,
-        ) ||
-        endpointChanged(
-          registered: await _store.registeredNcBaseUrl(),
-          current: _ncBaseUrl,
-        );
+    for (final type in PushRegistrationType.values) {
+      if (!await _store.isRegistered(type)) continue;
+      final changed =
+          endpointChanged(
+            registered: await _store.registeredProxyServer(type),
+            current: currentProxyServer,
+          ) ||
+          endpointChanged(
+            registered: await _store.registeredNcBaseUrl(type),
+            current: currentNcBaseUrl,
+          );
+      if (changed) return true;
+    }
+    return false;
   }
 
   /// Re-registers when the active endpoints diverge from the registered ones.
@@ -236,9 +362,10 @@ class PushRegistration {
   /// first, then the proxy) with the new token.
   Future<void> onTokenRefresh() => register();
 
-  /// Full teardown for logout: unregister push, revoke the app password, then
-  /// clear it locally. Ordered so the proxy stops pushing before credentials
-  /// are gone.
+  /// Full teardown for logout: unregister push, revoke BOTH app passwords
+  /// (each authenticated with itself — the endpoint revokes the credential it
+  /// is called with), then clear them locally. Ordered so the proxy stops
+  /// pushing before credentials are gone.
   Future<void> logoutCleanup() async {
     await unregister();
     try {
@@ -246,6 +373,16 @@ class PushRegistration {
     } on Object catch (e) {
       log('Push: delete app password failed: $e');
     }
+    try {
+      if (AccountData().hasAppPasswordTalk()) {
+        await DeleteAppPassword().run(
+          authorizationHeader: AccountData().getTalkBasicAuthHeader(),
+        );
+      }
+    } on Object catch (e) {
+      log('Push: delete talk app password failed: $e');
+    }
     await AccountData().clearAppPassword();
+    await AccountData().clearAppPasswordTalk();
   }
 }

lib/push/push_registration_store.dart

@@ -1,16 +1,25 @@
+import 'push_registration_type.dart';
 import 'push_secure_storage.dart';
 
-/// Persists the bookkeeping produced by a successful push registration:
-/// the Nextcloud device identifier, the per-user server public key (needed to
-/// verify incoming push signatures), the FCM token the registration was made
-/// with (so a token refresh can be detected) and the endpoints it was bound to
-/// (so an endpoint switch in the dev tools can be detected).
+/// Persists the bookkeeping produced by successful push registrations —
+/// per [PushRegistrationType]: the Nextcloud device identifier, the FCM token
+/// the registration was made with (so a token refresh can be detected), the
+/// endpoints it was bound to (so an endpoint switch in the dev tools can be
+/// detected) and the last attempt outcome. The server public key and the
+/// device keypair are shared between both registrations.
+///
+/// Key layout: the `general` type uses the pre-dual key names unchanged, so
+/// existing installs are implicitly migrated — their stored registration IS
+/// the general one; the missing talk registration is added by the next
+/// register-on-start self-heal.
 class PushRegistrationStore {
   static const _deviceIdentifierKey = 'push_device_identifier';
   static const _serverPublicKeyKey = 'push_server_public_key_pem';
   static const _registeredTokenKey = 'push_registered_fcm_token';
   static const _proxyServerKey = 'push_registered_proxy_server';
   static const _ncBaseUrlKey = 'push_registered_nc_base_url';
+  static const _lastAttemptAtKey = 'push_last_registration_at';
+  static const _lastAttemptErrorKey = 'push_last_registration_error';
   // Native-only context: the iOS AppDelegate answers Talk notification actions
   // (reply / mark-as-read) directly via URLSession while the Flutter engine is
   // not guaranteed to run. It needs the Nextcloud username and base URL from the
@@ -19,26 +28,46 @@ class PushRegistrationStore {
   static const _usernameKey = 'nextcloud_username';
   static const _baseUrlKey = 'nextcloud_base_url';
 
-  const PushRegistrationStore();
+  static const _perTypeKeys = [
+    _deviceIdentifierKey,
+    _registeredTokenKey,
+    _proxyServerKey,
+    _ncBaseUrlKey,
+    _lastAttemptAtKey,
+    _lastAttemptErrorKey,
+  ];
+
+  final FlutterSecureStorageLike _storage;
+
+  const PushRegistrationStore([this._storage = const PushSecureStorage()]);
+
+  /// Type-specific key: general keeps the legacy names (implicit migration of
+  /// pre-dual installs), talk appends a suffix.
+  static String keyFor(String baseKey, PushRegistrationType type) =>
+      type == PushRegistrationType.general ? baseKey : '${baseKey}_talk';
 
   Future<void> save({
+    required PushRegistrationType type,
     required String deviceIdentifier,
     required String serverPublicKeyPem,
     required String fcmToken,
     required String proxyServer,
     required String ncBaseUrl,
   }) async {
-    await pushSecureStorage.write(
-      key: _deviceIdentifierKey,
+    await _storage.write(
+      key: keyFor(_deviceIdentifierKey, type),
       value: deviceIdentifier,
     );
-    await pushSecureStorage.write(
-      key: _serverPublicKeyKey,
-      value: serverPublicKeyPem,
+    await _storage.write(key: _serverPublicKeyKey, value: serverPublicKeyPem);
+    await _storage.write(
+      key: keyFor(_registeredTokenKey, type),
+      value: fcmToken,
     );
-    await pushSecureStorage.write(key: _registeredTokenKey, value: fcmToken);
-    await pushSecureStorage.write(key: _proxyServerKey, value: proxyServer);
-    await pushSecureStorage.write(key: _ncBaseUrlKey, value: ncBaseUrl);
+    await _storage.write(
+      key: keyFor(_proxyServerKey, type),
+      value: proxyServer,
+    );
+    await _storage.write(key: keyFor(_ncBaseUrlKey, type), value: ncBaseUrl);
   }
 
   /// Persists the username and Nextcloud base URL group-scoped so the native
@@ -49,39 +78,73 @@ class PushRegistrationStore {
     required String username,
     required String baseUrl,
   }) async {
-    await pushSecureStorage.write(key: _usernameKey, value: username);
-    await pushSecureStorage.write(key: _baseUrlKey, value: baseUrl);
+    await _storage.write(key: _usernameKey, value: username);
+    await _storage.write(key: _baseUrlKey, value: baseUrl);
   }
 
-  Future<String?> deviceIdentifier() =>
-      pushSecureStorage.read(key: _deviceIdentifierKey);
+  Future<String?> deviceIdentifier(PushRegistrationType type) =>
+      _storage.read(key: keyFor(_deviceIdentifierKey, type));
 
+  /// Per-user server public key — identical for both registrations.
   Future<String?> serverPublicKeyPem() =>
-      pushSecureStorage.read(key: _serverPublicKeyKey);
+      _storage.read(key: _serverPublicKeyKey);
 
-  Future<String?> registeredFcmToken() =>
-      pushSecureStorage.read(key: _registeredTokenKey);
+  Future<String?> registeredFcmToken(PushRegistrationType type) =>
+      _storage.read(key: keyFor(_registeredTokenKey, type));
 
-  /// Proxy-server URL the current registration was made with.
-  Future<String?> registeredProxyServer() =>
-      pushSecureStorage.read(key: _proxyServerKey);
+  /// Proxy-server URL the registration of [type] was made with.
+  Future<String?> registeredProxyServer(PushRegistrationType type) =>
+      _storage.read(key: keyFor(_proxyServerKey, type));
 
-  /// Nextcloud base URL the current registration was made against.
-  Future<String?> registeredNcBaseUrl() =>
-      pushSecureStorage.read(key: _ncBaseUrlKey);
+  /// Nextcloud base URL the registration of [type] was made against.
+  Future<String?> registeredNcBaseUrl(PushRegistrationType type) =>
+      _storage.read(key: keyFor(_ncBaseUrlKey, type));
 
-  /// True when a registration has been persisted (used by the cold-start
-  /// self-heal to decide whether to (re-)register).
-  Future<bool> isRegistered() async =>
-      (await registeredFcmToken())?.isNotEmpty ?? false;
+  /// True when a registration of [type] has been persisted.
+  Future<bool> isRegistered(PushRegistrationType type) async =>
+      (await registeredFcmToken(type))?.isNotEmpty ?? false;
+
+  /// Records the outcome of the most recent registration attempt of [type] so
+  /// the push status view can show when it ran and why it failed. [error]
+  /// null = success (stored as empty string).
+  Future<void> saveLastRegistrationAttempt({
+    required PushRegistrationType type,
+    required DateTime at,
+    String? error,
+  }) async {
+    await _storage.write(
+      key: keyFor(_lastAttemptAtKey, type),
+      value: at.toIso8601String(),
+    );
+    await _storage.write(
+      key: keyFor(_lastAttemptErrorKey, type),
+      value: error ?? '',
+    );
+  }
+
+  /// Timestamp of the last registration attempt of [type], or null when none
+  /// ran yet.
+  Future<DateTime?> lastRegistrationAt(PushRegistrationType type) async {
+    final raw = await _storage.read(key: keyFor(_lastAttemptAtKey, type));
+    if (raw == null || raw.isEmpty) return null;
+    return DateTime.tryParse(raw);
+  }
+
+  /// Error text of the last registration attempt of [type], or null when it
+  /// succeeded (or never ran).
+  Future<String?> lastRegistrationError(PushRegistrationType type) async {
+    final raw = await _storage.read(key: keyFor(_lastAttemptErrorKey, type));
+    return (raw == null || raw.isEmpty) ? null : raw;
+  }
 
   Future<void> clear() async {
-    await pushSecureStorage.delete(key: _deviceIdentifierKey);
-    await pushSecureStorage.delete(key: _serverPublicKeyKey);
-    await pushSecureStorage.delete(key: _registeredTokenKey);
-    await pushSecureStorage.delete(key: _proxyServerKey);
-    await pushSecureStorage.delete(key: _ncBaseUrlKey);
-    await pushSecureStorage.delete(key: _usernameKey);
-    await pushSecureStorage.delete(key: _baseUrlKey);
+    for (final type in PushRegistrationType.values) {
+      for (final key in _perTypeKeys) {
+        await _storage.delete(key: keyFor(key, type));
+      }
+    }
+    await _storage.delete(key: _serverPublicKeyKey);
+    await _storage.delete(key: _usernameKey);
+    await _storage.delete(key: _baseUrlKey);
   }
 }

lib/push/push_registration_type.dart

@@ -0,0 +1,35 @@
+/// The two Nextcloud push registrations every device maintains.
+///
+/// Nextcloud routes Talk notifications ONLY to registrations whose session
+/// user agent matched `IRequest::USER_AGENT_TALK_*` (apptype `talk`) as soon
+/// as the user has at least one such device — e.g. the official Talk app.
+/// A single `unknown` registration therefore stops receiving Talk pushes the
+/// moment the official app is installed. The fix is one registration per
+/// route, sharing the same device keypair.
+enum PushRegistrationType {
+  /// Default registration (apptype `unknown`): files, calendar, everything
+  /// except Talk.
+  general('general'),
+
+  /// Talk registration (apptype `talk`): Talk messages and calls, ranking
+  /// equally beside the official Talk app.
+  talk('talk');
+
+  /// Value sent to MarianumConnect as `registrationType`.
+  final String wireName;
+
+  const PushRegistrationType(this.wireName);
+}
+
+/// Pseudo push token whose sha512 is registered with Nextcloud. The two
+/// registrations MUST carry different pushTokenHashes: on registration NC's
+/// `deletePushTokenByHash()` removes older subscriptions of the same user
+/// with an identical hash — identical hashes would let each registration
+/// delete its sibling. The backend derives the same variants from the real
+/// FCM token (`registrationType` field), so the proxy hash comparison still
+/// matches. Nextcloud never sees the plain token either way.
+String pushTokenVariant(String fcmToken, PushRegistrationType type) =>
+    switch (type) {
+      PushRegistrationType.general => fcmToken,
+      PushRegistrationType.talk => '$fcmToken#talk',
+    };

lib/push/push_renderer.dart

@@ -1,17 +1,22 @@
+import 'dart:async';
 import 'dart:convert';
+import 'dart:developer';
 
 import 'package:flutter_local_notifications/flutter_local_notifications.dart';
 
 import '../notification/notification_service.dart';
-import '../notification/notification_tasks.dart';
+import '../theming/light_app_theme.dart';
+import 'chat_thread_store.dart';
 import 'nid_store.dart';
 import 'push_actions.dart';
+import 'push_avatar.dart';
 import 'push_subject.dart';
 
 /// Renders decrypted push subjects (and plaintext Connect pushes) as local
-/// notifications. Talk messages get a [MessagingStyleInformation] with inline
-/// reply + mark-as-read actions and a per-chat tag; everything else renders in
-/// a generic channel.
+/// notifications. Talk messages of one chat stack into a SINGLE
+/// [MessagingStyleInformation] notification (stable id/tag per chat, history
+/// from [ChatThreadStore]) with inline reply + mark-as-read actions;
+/// everything else renders in a generic channel.
 class PushRenderer {
   static const talkChannelId = 'talk_messages';
   static const talkChannelName = 'Talk-Nachrichten';
@@ -20,9 +25,21 @@ class PushRenderer {
 
   static const String iosTalkCategory = 'TALK_MESSAGE';
 
-  final NidStore _nidStore;
+  /// Brand accent: colors the (monochrome) small icon and action buttons in
+  /// the notification shade instead of the default grey.
+  static const _accentColor = LightAppTheme.marianumRed;
 
-  PushRenderer({NidStore? nidStore}) : _nidStore = nidStore ?? NidStore();
+  final NidStore _nidStore;
+  final PushAvatarStore _avatarStore;
+  final ChatThreadStore _threadStore;
+
+  PushRenderer({
+    NidStore? nidStore,
+    PushAvatarStore? avatarStore,
+    ChatThreadStore? threadStore,
+  }) : _nidStore = nidStore ?? NidStore(),
+       _avatarStore = avatarStore ?? PushAvatarStore(),
+       _threadStore = threadStore ?? ChatThreadStore();
 
   FlutterLocalNotificationsPlugin get _plugin =>
       NotificationService().flutterLocalNotificationsPlugin;
@@ -60,24 +77,120 @@ class PushRenderer {
     }
   }
 
+  /// Tri-state probe of whether this chat's stacked notification is still in
+  /// the tray. `null` when the query fails or isn't supported (native code not
+  /// linked, older platform) — the caller then keeps stacking defensively. A
+  /// successful query is authoritative: absence means dismissed/read.
+  /// Works in the background isolate (pure plugin call, no BuildContext).
+  Future<bool?> _isChatNotificationActive(String chatToken) async {
+    final id = stableChatNotificationId(chatToken);
+    final tag = chatNotificationTag(chatToken);
+    try {
+      final actives = await _plugin.getActiveNotifications();
+      return actives.any((n) => n.id == id || n.tag == tag);
+    } on Object catch (e) {
+      log('Push: getActiveNotifications probe failed: $e');
+      return null;
+    }
+  }
+
   Future<void> _renderTalk(PushSubject subject) async {
-    final nid = subject.nid ?? _fallbackId(subject.id);
     final chatToken = subject.id;
-    final tag = chatToken != null
-        ? NotificationTasks.chatTag(chatToken)
-        : 'talk_$nid';
-    final text = subject.subject ?? 'Neue Nachricht';
-    final (senderName, messageText) = _splitSender(text);
+    final parsed = parseTalkSubject(subject.subject ?? 'Neue Nachricht');
+    final nid =
+        subject.nid ??
+        _fallbackId('${chatToken ?? ''}${parsed.sender}${parsed.text}');
 
-    final payload = _payload(chatToken: chatToken, nid: nid);
+    if (chatToken == null || chatToken.isEmpty) {
+      // Without a chat token there is nothing to stack under — render a
+      // standalone card keyed by the nid.
+      await _renderTalkStandalone(nid, parsed.sender, parsed.text);
+      return;
+    }
 
+    // Restart the thread when the previous notification is gone (swiped away
+    // or the chat was read without our cleanup running) — otherwise the new
+    // push would resurrect the already-seen history. A failed/unsupported
+    // probe keeps stacking (see threadAfterIncoming).
+    final isActive = await _isChatNotificationActive(chatToken);
+    final messages = await _threadStore.appendConsideringActive(
+      chatToken,
+      ThreadMessage(
+        nid: nid,
+        sender: parsed.sender,
+        text: parsed.text,
+        timestampMs: DateTime.now().millisecondsSinceEpoch,
+        roomName: parsed.roomName,
+      ),
+      isActive,
+    );
+    await _nidStore.put(
+      NidEntry(
+        nid: nid,
+        notificationId: stableChatNotificationId(chatToken),
+        tag: chatNotificationTag(chatToken),
+        chatToken: chatToken,
+      ),
+    );
+    await renderTalkThread(chatToken, messages);
+  }
+
+  /// Shows/updates the ONE stacked notification of [chatToken] from the given
+  /// history. Identity is stable per chat ([stableChatNotificationId] +
+  /// [chatNotificationTag]) so each new message updates the same card.
+  /// [alert] false re-renders silently — used when a delete-push removed one
+  /// of several messages and the remaining thread must not ping again.
+  Future<void> renderTalkThread(
+    String chatToken,
+    List<ThreadMessage> messages, {
+    bool alert = true,
+  }) async {
+    if (messages.isEmpty) return;
+    final tag = chatNotificationTag(chatToken);
+    final id = stableChatNotificationId(chatToken);
+    final latest = messages.last;
+
+    // Conversation avatar (the person's picture in 1:1 chats), pre-masked
+    // round. Bounded by the store's fetch timeout; when the icon isn't ready
+    // in time the notification renders without it and a still-running fetch
+    // triggers ONE silent re-render below once bytes arrive.
+    final lookup = await _avatarStore.roomAvatarIcon(chatToken);
+    final avatarBytes = lookup.icon;
+    if (alert && avatarBytes == null && lookup.late != null) {
+      unawaited(
+        lookup.late!.then((bytes) async {
+          if (bytes == null) return;
+          final fresh = await _threadStore.messages(chatToken);
+          if (fresh.isEmpty) return;
+          // Re-render hits the processed cache → icon present, no re-schedule.
+          await renderTalkThread(chatToken, fresh, alert: false);
+        }),
+      );
+    }
+    final senders = <String, Person>{};
+    Person personFor(String sender) => senders.putIfAbsent(
+      sender,
+      () => Person(
+        key: sender,
+        name: sender,
+        icon: avatarBytes == null ? null : ByteArrayAndroidIcon(avatarBytes),
+      ),
+    );
+
+    final styleMessages = [
+      for (final m in messages)
+        Message(
+          m.text,
+          DateTime.fromMillisecondsSinceEpoch(m.timestampMs),
+          personFor(m.sender),
+        ),
+    ];
+    final header = conversationHeader(messages);
     final messagingStyle = MessagingStyleInformation(
       const Person(key: 'self', name: 'Ich'),
-      conversationTitle: senderName,
-      groupConversation: false,
-      messages: [
-        Message(messageText, DateTime.now(), Person(name: senderName)),
-      ],
+      conversationTitle: header.conversationTitle,
+      groupConversation: header.groupConversation,
+      messages: styleMessages,
     );
 
     final androidDetails = AndroidNotificationDetails(
@@ -86,50 +199,89 @@ class PushRenderer {
       importance: Importance.high,
       priority: Priority.high,
       category: AndroidNotificationCategory.message,
+      color: _accentColor,
       tag: tag,
+      silent: !alert,
       styleInformation: messagingStyle,
-      actions: const [
-        AndroidNotificationAction(
-          kTalkReplyActionId,
-          'Antworten',
-          showsUserInterface: false,
-          cancelNotification: false,
-          inputs: [AndroidNotificationActionInput(label: 'Nachricht')],
-        ),
-        AndroidNotificationAction(
-          kTalkMarkReadActionId,
-          'Gelesen',
-          showsUserInterface: false,
-        ),
-      ],
+      actions: _talkActions,
     );
 
     final iosDetails = DarwinNotificationDetails(
       threadIdentifier: tag,
       categoryIdentifier: iosTalkCategory,
+      presentSound: alert ? null : false,
+      presentBanner: alert ? null : false,
     );
 
-    await _nidStore.put(
-      NidEntry(nid: nid, notificationId: nid, tag: tag, chatToken: chatToken),
+    await _plugin.show(
+      id: id,
+      title: latest.sender,
+      body: latest.text,
+      notificationDetails: NotificationDetails(
+        android: androidDetails,
+        iOS: iosDetails,
+      ),
+      payload: _payload(chatToken: chatToken, nid: latest.nid),
     );
+  }
 
+  Future<void> _renderTalkStandalone(
+    int nid,
+    String senderName,
+    String messageText,
+  ) async {
+    final tag = 'talk_$nid';
+    await _nidStore.put(NidEntry(nid: nid, notificationId: nid, tag: tag));
     await _plugin.show(
       id: nid,
       title: senderName,
       body: messageText,
       notificationDetails: NotificationDetails(
-        android: androidDetails,
-        iOS: iosDetails,
+        android: AndroidNotificationDetails(
+          talkChannelId,
+          talkChannelName,
+          importance: Importance.high,
+          priority: Priority.high,
+          category: AndroidNotificationCategory.message,
+          color: _accentColor,
+          tag: tag,
+          // Single sender ⇒ no conversationTitle (1:1 convention): the sender
+          // Person is the header, a title would repeat the name per line.
+          styleInformation: MessagingStyleInformation(
+            const Person(key: 'self', name: 'Ich'),
+            groupConversation: false,
+            messages: [
+              Message(messageText, DateTime.now(), Person(name: senderName)),
+            ],
+          ),
+        ),
+        iOS: const DarwinNotificationDetails(),
       ),
-      payload: payload,
+      payload: _payload(chatToken: null, nid: nid),
     );
   }
 
+  static const _talkActions = [
+    AndroidNotificationAction(
+      kTalkReplyActionId,
+      'Antworten',
+      showsUserInterface: false,
+      cancelNotification: false,
+      inputs: [AndroidNotificationActionInput(label: 'Nachricht')],
+    ),
+    AndroidNotificationAction(
+      kTalkMarkReadActionId,
+      'Gelesen',
+      showsUserInterface: false,
+    ),
+  ];
+
   Future<void> _renderGeneric(PushSubject subject) async {
     final nid = subject.nid ?? _fallbackId(subject.subject);
     const androidDetails = AndroidNotificationDetails(
       generalChannelId,
       generalChannelName,
+      color: _accentColor,
     );
     const iosDetails = DarwinNotificationDetails();
     await _nidStore.put(
@@ -160,6 +312,7 @@ class PushRenderer {
       generalChannelName,
       importance: Importance.high,
       priority: Priority.high,
+      color: _accentColor,
     );
     await _plugin.show(
       id: id,
@@ -173,16 +326,6 @@ class PushRenderer {
   String _payload({required String? chatToken, required int nid}) =>
       jsonEncode({'chatToken': ?chatToken, 'nid': nid});
 
-  /// Splits a `"Sender: message"` subject into its parts, falling back to a
-  /// generic sender label when there's no delimiter.
-  (String, String) _splitSender(String subject) {
-    final idx = subject.indexOf(': ');
-    if (idx > 0 && idx < subject.length - 2) {
-      return (subject.substring(0, idx), subject.substring(idx + 2));
-    }
-    return ('Talk', subject);
-  }
-
   /// Deterministic non-negative 31-bit id from a string, used when the push
   /// carries no `nid`.
   int _fallbackId(String? seed) {

lib/push/push_secure_storage.dart

@@ -25,3 +25,28 @@ const IOSOptions kPushIosOptions = IOSOptions(
 const FlutterSecureStorage pushSecureStorage = FlutterSecureStorage(
   iOptions: kPushIosOptions,
 );
+
+/// Minimal storage contract so tests can inject an in-memory fake instead of
+/// touching the platform keystore.
+abstract class FlutterSecureStorageLike {
+  Future<String?> read({required String key});
+  Future<void> write({required String key, required String? value});
+  Future<void> delete({required String key});
+}
+
+/// Default [FlutterSecureStorageLike] backed by [pushSecureStorage].
+class PushSecureStorage implements FlutterSecureStorageLike {
+  const PushSecureStorage();
+
+  @override
+  Future<String?> read({required String key}) =>
+      pushSecureStorage.read(key: key);
+
+  @override
+  Future<void> write({required String key, required String? value}) =>
+      pushSecureStorage.write(key: key, value: value);
+
+  @override
+  Future<void> delete({required String key}) =>
+      pushSecureStorage.delete(key: key);
+}

lib/push/push_status.dart

@@ -0,0 +1,278 @@
+import 'package:firebase_messaging/firebase_messaging.dart';
+import 'package:flutter/foundation.dart';
+
+import '../model/account_data.dart';
+import 'push_keypair.dart';
+import 'push_registration.dart';
+import 'push_registration_store.dart';
+import 'push_registration_type.dart';
+
+/// Tri-state result of a single push-chain check.
+enum PushCheck { ok, fail, unknown }
+
+/// State of one of the two registrations (general/talk) — Nextcloud binding,
+/// proxy binding and last attempt outcome.
+@immutable
+class PushTypeStatus {
+  /// Nextcloud subscription present (device identifier stored).
+  final bool nextcloudRegistered;
+  final String? registeredNcBaseUrl;
+  final String? registeredProxyServer;
+  final DateTime? lastRegistrationAt;
+
+  /// Error text of the last registration attempt; null = success or never ran.
+  final String? lastRegistrationError;
+
+  const PushTypeStatus({
+    required this.nextcloudRegistered,
+    required this.registeredNcBaseUrl,
+    required this.registeredProxyServer,
+    required this.lastRegistrationAt,
+    required this.lastRegistrationError,
+  });
+}
+
+/// Snapshot of every link in the push chain, in delivery order. Pure data —
+/// the display rows are derived by [buildPushStatusRows] so the mapping is
+/// unit-testable without any plugin.
+@immutable
+class PushStatusReport {
+  final bool settingEnabled;
+  final PushCheck osPermission;
+
+  /// Backend capability `pushNotifications`; [PushCheck.unknown] while the
+  /// capabilities have not been loaded yet this session.
+  final PushCheck serverCapability;
+  final bool appPasswordPresent;
+  final bool talkAppPasswordPresent;
+  final bool keypairPresent;
+
+  /// State of the general (apptype unknown) registration.
+  final PushTypeStatus general;
+
+  /// State of the Talk-classified registration.
+  final PushTypeStatus talk;
+
+  final String? currentProxyServer;
+
+  const PushStatusReport({
+    required this.settingEnabled,
+    required this.osPermission,
+    required this.serverCapability,
+    required this.appPasswordPresent,
+    required this.talkAppPasswordPresent,
+    required this.keypairPresent,
+    required this.general,
+    required this.talk,
+    required this.currentProxyServer,
+  });
+
+  /// True when the stored proxy binding of [status] diverges from the active
+  /// endpoint.
+  bool proxyEndpointMismatch(PushTypeStatus status) =>
+      currentProxyServer != null &&
+      PushRegistration.endpointChanged(
+        registered: status.registeredProxyServer,
+        current: currentProxyServer!,
+      );
+
+  /// True when a test notification can actually be delivered. The test push
+  /// is a Connect direct push routed via the general registration, so a
+  /// healthy general chain suffices — a broken talk registration only affects
+  /// Talk message delivery. The OS permission must not be denied (`unknown`
+  /// stays permissive, mirroring [PushRegistration.isPermissionUsable]).
+  bool get readyForTestNotification =>
+      osPermission != PushCheck.fail &&
+      general.nextcloudRegistered &&
+      (general.registeredProxyServer?.isNotEmpty ?? false) &&
+      !proxyEndpointMismatch(general) &&
+      general.lastRegistrationError == null;
+}
+
+/// Collects the current push chain state. Settings/capability flags come from
+/// the caller (they live in cubits); everything else is read from the secure
+/// stores and the messaging plugin.
+Future<PushStatusReport> collectPushStatus({
+  required bool settingEnabled,
+  required bool capabilityPush,
+  required bool capabilitiesLoaded,
+  PushRegistrationStore store = const PushRegistrationStore(),
+  PushKeypair keypair = const PushKeypair(),
+}) async {
+  final registration = PushRegistration();
+
+  String? currentProxy;
+  try {
+    currentProxy = registration.currentProxyServer;
+  } on Object {
+    currentProxy = null;
+  }
+
+  Future<PushTypeStatus> typeStatus(PushRegistrationType type) async =>
+      PushTypeStatus(
+        nextcloudRegistered:
+            (await store.deviceIdentifier(type))?.isNotEmpty ?? false,
+        registeredNcBaseUrl: await store.registeredNcBaseUrl(type),
+        registeredProxyServer: await store.registeredProxyServer(type),
+        lastRegistrationAt: await store.lastRegistrationAt(type),
+        lastRegistrationError: await store.lastRegistrationError(type),
+      );
+
+  return PushStatusReport(
+    settingEnabled: settingEnabled,
+    osPermission: await _osPermission(),
+    serverCapability: !capabilitiesLoaded
+        ? PushCheck.unknown
+        : (capabilityPush ? PushCheck.ok : PushCheck.fail),
+    appPasswordPresent: AccountData().hasAppPassword(),
+    talkAppPasswordPresent: AccountData().hasAppPasswordTalk(),
+    keypairPresent: (await keypair.loadPublicKeyPem())?.isNotEmpty ?? false,
+    general: await typeStatus(PushRegistrationType.general),
+    talk: await typeStatus(PushRegistrationType.talk),
+    currentProxyServer: currentProxy,
+  );
+}
+
+Future<PushCheck> _osPermission() async {
+  try {
+    final settings = await FirebaseMessaging.instance.getNotificationSettings();
+    switch (settings.authorizationStatus) {
+      case AuthorizationStatus.authorized:
+      case AuthorizationStatus.provisional:
+        return PushCheck.ok;
+      case AuthorizationStatus.denied:
+        return PushCheck.fail;
+      case AuthorizationStatus.notDetermined:
+        return PushCheck.unknown;
+    }
+  } on Object {
+    return PushCheck.unknown;
+  }
+}
+
+/// One line in the status checklist.
+@immutable
+class PushStatusRow {
+  final String label;
+  final PushCheck state;
+
+  /// Short explanation shown as subtitle — set for failures (what to do) and
+  /// for informational details (e.g. the registered URL).
+  final String? detail;
+
+  const PushStatusRow({required this.label, required this.state, this.detail});
+}
+
+const _pendingDetail =
+    'Registrierung ausstehend — sie wird beim nächsten App-Start '
+    'automatisch wiederholt';
+
+/// Derives the display checklist from a [PushStatusReport]. Pure — the order
+/// mirrors the actual chain: setting → OS → server → credentials → keys →
+/// Nextcloud (general/talk) → Connect (general/talk).
+List<PushStatusRow> buildPushStatusRows(PushStatusReport r) => [
+  PushStatusRow(
+    label: 'Push-Benachrichtigungen aktiviert',
+    state: r.settingEnabled ? PushCheck.ok : PushCheck.fail,
+    detail: r.settingEnabled
+        ? null
+        : 'In den Einstellungen deaktiviert — über den Schalter oben aktivieren',
+  ),
+  PushStatusRow(
+    label: 'Benachrichtigungsberechtigung',
+    state: r.osPermission,
+    detail: switch (r.osPermission) {
+      PushCheck.ok => null,
+      PushCheck.fail =>
+        'Die Benachrichtigungsberechtigung wurde in den Systemeinstellungen '
+            'deaktiviert',
+      PushCheck.unknown => 'Noch nicht erteilt',
+    },
+  ),
+  PushStatusRow(
+    label: 'Server-Unterstützung',
+    state: r.serverCapability,
+    detail: switch (r.serverCapability) {
+      PushCheck.ok => null,
+      PushCheck.fail =>
+        'Der Server unterstützt Push-Benachrichtigungen derzeit nicht',
+      PushCheck.unknown => 'Serverinformationen noch nicht geladen',
+    },
+  ),
+  PushStatusRow(
+    label: 'App-Passwörter',
+    state: r.appPasswordPresent && r.talkAppPasswordPresent
+        ? PushCheck.ok
+        : PushCheck.fail,
+    detail: r.appPasswordPresent && r.talkAppPasswordPresent
+        ? null
+        : '${_missingPasswords(r)} — wird beim nächsten App-Start '
+              'automatisch angefordert',
+  ),
+  PushStatusRow(
+    label: 'Geräteschlüssel',
+    state: r.keypairPresent ? PushCheck.ok : PushCheck.fail,
+    detail: r.keypairPresent
+        ? null
+        : 'Nicht vorhanden — wird bei der nächsten Registrierung erzeugt',
+  ),
+  _nextcloudRow(r.general, 'Nextcloud-Registrierung (Allgemein)'),
+  _nextcloudRow(r.talk, 'Nextcloud-Registrierung (Talk)'),
+  _connectRow(r, r.general, 'Connect-Registrierung (Allgemein)'),
+  _connectRow(r, r.talk, 'Connect-Registrierung (Talk)'),
+];
+
+String _missingPasswords(PushStatusReport r) {
+  if (!r.appPasswordPresent && !r.talkAppPasswordPresent) {
+    return 'Beide fehlen';
+  }
+  return r.appPasswordPresent
+      ? 'Talk-App-Passwort fehlt'
+      : 'Allgemeines App-Passwort fehlt';
+}
+
+PushStatusRow _nextcloudRow(PushTypeStatus status, String label) =>
+    PushStatusRow(
+      label: label,
+      state: status.nextcloudRegistered ? PushCheck.ok : PushCheck.fail,
+      detail: status.nextcloudRegistered
+          ? status.registeredNcBaseUrl
+          : _pendingDetail,
+    );
+
+PushStatusRow _connectRow(
+  PushStatusReport r,
+  PushTypeStatus status,
+  String label,
+) {
+  final registeredProxy = status.registeredProxyServer;
+  if (registeredProxy == null || registeredProxy.isEmpty) {
+    return PushStatusRow(
+      label: label,
+      state: PushCheck.fail,
+      detail: _pendingDetail,
+    );
+  }
+  if (r.proxyEndpointMismatch(status)) {
+    return PushStatusRow(
+      label: label,
+      state: PushCheck.fail,
+      detail:
+          'Für $registeredProxy registriert — der aktive Server ist '
+          '${r.currentProxyServer}. Eine erneute Registrierung ist '
+          'erforderlich.',
+    );
+  }
+  if (status.lastRegistrationError != null) {
+    return PushStatusRow(
+      label: label,
+      state: PushCheck.fail,
+      detail: 'Die letzte Registrierung ist fehlgeschlagen — Details unten',
+    );
+  }
+  return PushStatusRow(
+    label: label,
+    state: PushCheck.ok,
+    detail: registeredProxy,
+  );
+}

lib/push/push_subject.dart

@@ -1,3 +1,42 @@
+/// Parsed parts of a Talk push subject text.
+///
+/// Format verified against nextcloud/spreed `Notifier::parseChatMessage`:
+/// with message preview the parsed subject is `"{user}\n{message}"` for 1:1
+/// chats and `'{user} in {call}' . "\n{message}"` for groups — header and
+/// message are separated by a NEWLINE, and the notifications app forwards the
+/// parsed subject unmodified (only shortened). The German translation of
+/// `{user} in {call}` is identical (`l10n/de.json`), so the ` in ` separator
+/// holds for de_DE. Legacy/other variants using `": "` are kept as fallback;
+/// splitting the header at the LAST ` in ` is robust against sender names
+/// containing "in" (only a display name literally containing ` in ` in a 1:1
+/// chat would still mis-split — accepted heuristic limit).
+({String sender, String? roomName, String text}) parseTalkSubject(String raw) {
+  String header;
+  String text;
+  final newline = raw.indexOf('\n');
+  if (newline > 0) {
+    header = raw.substring(0, newline).trim();
+    text = raw.substring(newline + 1);
+  } else {
+    final colon = raw.indexOf(': ');
+    if (colon > 0 && colon < raw.length - 2) {
+      header = raw.substring(0, colon);
+      text = raw.substring(colon + 2);
+    } else {
+      return (sender: 'Talk', roomName: null, text: raw);
+    }
+  }
+  final roomSep = header.lastIndexOf(' in ');
+  if (roomSep > 0 && roomSep + 4 < header.length) {
+    return (
+      sender: header.substring(0, roomSep),
+      roomName: header.substring(roomSep + 4),
+      text: text,
+    );
+  }
+  return (sender: header, roomName: null, text: text);
+}
+
 /// The decrypted `subject` JSON of a Nextcloud push-v2 notification.
 ///
 /// Covers the full shape the notifications app emits, including the three

lib/view/pages/settings/sections/talk_section.dart

@@ -3,14 +3,12 @@ import 'dart:async';
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 
-import '../../../../api/errors/error_mapper.dart';
-import '../../../../api/marianumconnect/queries/push_device_test/push_device_test.dart';
 import '../../../../push/push_registration.dart';
-import '../../../../push/push_registration_store.dart';
 import '../../../../routing/app_routes.dart';
 import '../../../../state/app/modules/settings/bloc/settings_cubit.dart';
 import '../../../../utils/haptics.dart';
 import '../../../../widget/centered_leading.dart';
+import '../widgets/push_status_sheet.dart';
 
 class TalkSection extends StatelessWidget {
   const TalkSection({super.key});
@@ -56,7 +54,9 @@ class TalkSection extends StatelessWidget {
             Icon(Icons.notifications_active_outlined),
           ),
           title: const Text('Push-Benachrichtigungen'),
-          subtitle: const Text('Neue Talk-Nachrichten direkt aufs Gerät'),
+          subtitle: const Text(
+            'Benachrichtigungen bei neuen Talk-Nachrichten erhalten',
+          ),
           trailing: Checkbox(
             value: notificationSettings.enabled,
             onChanged: (e) {
@@ -74,8 +74,9 @@ class TalkSection extends StatelessWidget {
                     messenger.showSnackBar(
                       const SnackBar(
                         content: Text(
-                          'Benachrichtigungen sind in den Systemeinstellungen '
-                          'deaktiviert — bitte dort erlauben.',
+                          'Die Benachrichtigungsberechtigung wurde in den '
+                          'Systemeinstellungen deaktiviert. Bitte aktiviere '
+                          'sie dort, um Push-Benachrichtigungen zu erhalten.',
                         ),
                       ),
                     );
@@ -87,102 +88,14 @@ class TalkSection extends StatelessWidget {
             },
           ),
         ),
-        if (notificationSettings.enabled) const _TestNotificationTile(),
+        ListTile(
+          leading: const CenteredLeading(Icon(Icons.monitor_heart_outlined)),
+          title: const Text('Push-Status'),
+          subtitle: const Text('Registrierung und Zustellung im Detail'),
+          trailing: const Icon(Icons.arrow_right),
+          onTap: () => showPushStatusSheet(context),
+        ),
       ],
     );
   }
 }
-
-/// "Send a test notification" action, shown only while push is enabled. The
-/// button stays disabled until a registration is confirmed present, then calls
-/// the backend and reports the result via a SnackBar.
-class _TestNotificationTile extends StatefulWidget {
-  const _TestNotificationTile();
-
-  @override
-  State<_TestNotificationTile> createState() => _TestNotificationTileState();
-}
-
-class _TestNotificationTileState extends State<_TestNotificationTile> {
-  static const _permissionDeniedHint =
-      'Benachrichtigungen sind in den Systemeinstellungen deaktiviert';
-
-  bool _registered = false;
-  bool _permissionDenied = false;
-  bool _sending = false;
-
-  @override
-  void initState() {
-    super.initState();
-    _loadState();
-  }
-
-  Future<void> _loadState() async {
-    final registered = await const PushRegistrationStore().isRegistered();
-    final denied = await PushRegistration.isOsPermissionDenied();
-    if (!mounted) return;
-    setState(() {
-      _registered = registered;
-      _permissionDenied = denied;
-    });
-  }
-
-  Future<void> _sendTest() async {
-    if (_sending) return;
-    Haptics.selection();
-    final messenger = ScaffoldMessenger.of(context);
-    // Re-check right before sending: the user may have flipped the OS
-    // permission in the system settings since this tile was built.
-    final denied = await PushRegistration.isOsPermissionDenied();
-    if (!mounted) return;
-    if (denied) {
-      setState(() => _permissionDenied = true);
-      messenger.showSnackBar(
-        const SnackBar(
-          content: Text('$_permissionDeniedHint — bitte dort erlauben.'),
-        ),
-      );
-      return;
-    }
-    setState(() {
-      _permissionDenied = false;
-      _sending = true;
-    });
-    String message;
-    try {
-      final devices = await PushDeviceTest().run();
-      message = devices >= 1
-          ? 'Testbenachrichtigung an $devices Gerät(e) gesendet'
-          : 'Kein Gerät registriert — Push-Registrierung prüfen';
-    } on Object catch (e) {
-      message = errorToUserMessage(e);
-    }
-    if (!mounted) return;
-    setState(() => _sending = false);
-    messenger.showSnackBar(SnackBar(content: Text(message)));
-  }
-
-  @override
-  Widget build(BuildContext context) {
-    if (!_registered) return const SizedBox.shrink();
-    return ListTile(
-      leading: const CenteredLeading(Icon(Icons.send_outlined)),
-      title: const Text('Testbenachrichtigung senden'),
-      subtitle: _permissionDenied
-          ? Text(
-              _permissionDeniedHint,
-              style: TextStyle(color: Theme.of(context).colorScheme.error),
-            )
-          : const Text('Prüft, ob Push auf diesem Gerät ankommt'),
-      trailing: _sending
-          ? const SizedBox(
-              width: 20,
-              height: 20,
-              child: CircularProgressIndicator(strokeWidth: 2),
-            )
-          : const Icon(Icons.arrow_right),
-      enabled: !_sending,
-      onTap: _sending ? null : _sendTest,
-    );
-  }
-}

lib/view/pages/settings/widgets/push_status_sheet.dart

@@ -0,0 +1,249 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
+
+import '../../../../api/errors/error_mapper.dart';
+import '../../../../api/marianumconnect/queries/push_device_test/push_device_test.dart';
+import '../../../../extensions/date_time.dart';
+import '../../../../push/push_registration.dart';
+import '../../../../push/push_status.dart';
+import '../../../../state/app/modules/capabilities/bloc/capabilities_cubit.dart';
+import '../../../../state/app/modules/settings/bloc/settings_cubit.dart';
+import '../../../../widget/app_progress_indicator.dart';
+import '../../../../widget/details_bottom_sheet.dart';
+
+/// Opens the push status checklist: one row per link in the push chain with
+/// an explanation where it is broken, the last registration attempt (incl.
+/// verbatim error), a manual re-register action and — once the chain is
+/// operational — a test notification. Loads once on open; the refresh action
+/// re-collects on demand (no polling).
+void showPushStatusSheet(BuildContext context) {
+  // Captured here: the sheet outlives this build context's element tree.
+  final settings = context.read<SettingsCubit>();
+  final capabilities = context.read<CapabilitiesCubit>();
+  showDetailsBottomSheet(
+    context,
+    header: const ListTile(
+      leading: Icon(Icons.monitor_heart_outlined),
+      title: Text('Status der Push-Benachrichtigungen'),
+    ),
+    children: (sheetCtx) => [
+      _PushStatusBody(settings: settings, capabilities: capabilities),
+    ],
+  );
+}
+
+class _PushStatusBody extends StatefulWidget {
+  final SettingsCubit settings;
+  final CapabilitiesCubit capabilities;
+
+  const _PushStatusBody({required this.settings, required this.capabilities});
+
+  @override
+  State<_PushStatusBody> createState() => _PushStatusBodyState();
+}
+
+class _PushStatusBodyState extends State<_PushStatusBody> {
+  PushStatusReport? _report;
+  bool _busy = false;
+
+  @override
+  void initState() {
+    super.initState();
+    _load();
+  }
+
+  Future<void> _load() async {
+    final capabilitiesState = widget.capabilities.state;
+    final report = await collectPushStatus(
+      settingEnabled: widget.settings.val().notificationSettings.enabled,
+      capabilityPush: capabilitiesState.pushNotifications,
+      capabilitiesLoaded: capabilitiesState.loaded,
+    );
+    if (!mounted) return;
+    setState(() => _report = report);
+  }
+
+  Future<void> _reRegister() async {
+    if (_busy) return;
+    setState(() => _busy = true);
+    final messenger = ScaffoldMessenger.of(context);
+    final ok = await PushRegistration().register();
+    if (!mounted) return;
+    setState(() => _busy = false);
+    await _load();
+    messenger.showSnackBar(
+      SnackBar(
+        content: Text(
+          ok
+              ? 'Registrierung erfolgreich abgeschlossen'
+              : 'Registrierung fehlgeschlagen — Details in der Statusübersicht',
+        ),
+      ),
+    );
+  }
+
+  Future<void> _sendTest() async {
+    if (_busy) return;
+    setState(() => _busy = true);
+    final messenger = ScaffoldMessenger.of(context);
+    String message;
+    try {
+      final devices = await PushDeviceTest().run();
+      message = switch (devices) {
+        0 => 'Es ist kein Gerät registriert — bitte erneut registrieren',
+        1 => 'Testbenachrichtigung an 1 Gerät gesendet',
+        _ => 'Testbenachrichtigung an $devices Geräte gesendet',
+      };
+    } on Object catch (e) {
+      message = errorToUserMessage(e);
+    }
+    if (!mounted) return;
+    setState(() => _busy = false);
+    messenger.showSnackBar(SnackBar(content: Text(message)));
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final report = _report;
+    if (report == null) {
+      return const Padding(
+        padding: EdgeInsets.all(32),
+        child: Center(child: AppProgressIndicator.medium()),
+      );
+    }
+    final theme = Theme.of(context);
+    final rows = buildPushStatusRows(report);
+    return Column(
+      mainAxisSize: MainAxisSize.min,
+      crossAxisAlignment: CrossAxisAlignment.stretch,
+      children: [
+        ...rows.map(
+          (row) => ListTile(
+            dense: true,
+            leading: _stateIcon(row.state, theme),
+            title: Text(row.label),
+            subtitle: row.detail == null ? null : Text(row.detail!),
+          ),
+        ),
+        if (report.general.lastRegistrationAt != null ||
+            report.talk.lastRegistrationAt != null)
+          const Divider(height: 1),
+        ..._lastAttempt(theme, 'Allgemein', report.general),
+        ..._lastAttempt(theme, 'Talk', report.talk),
+        Padding(
+          padding: const EdgeInsets.fromLTRB(16, 8, 16, 0),
+          child: _actions(report),
+        ),
+      ],
+    );
+  }
+
+  /// Last-attempt line (+ verbatim error) for one registration type.
+  List<Widget> _lastAttempt(
+    ThemeData theme,
+    String label,
+    PushTypeStatus status,
+  ) {
+    final at = status.lastRegistrationAt;
+    if (at == null) return const [];
+    final error = status.lastRegistrationError;
+    return [
+      ListTile(
+        dense: true,
+        leading: Icon(
+          error == null ? Icons.history : Icons.error_outline,
+          color: error == null ? null : theme.colorScheme.error,
+        ),
+        title: Text(
+          'Letzte Registrierung ($label): ${at.formatDateTime()} — '
+          '${error == null ? 'erfolgreich' : 'fehlgeschlagen'}',
+        ),
+      ),
+      if (error != null)
+        Padding(
+          padding: const EdgeInsets.fromLTRB(16, 0, 16, 8),
+          child: Container(
+            width: double.infinity,
+            padding: const EdgeInsets.all(12),
+            decoration: BoxDecoration(
+              color: theme.colorScheme.surfaceContainerHighest,
+              borderRadius: BorderRadius.circular(8),
+            ),
+            child: Text(
+              error,
+              style: TextStyle(
+                fontFamily: 'monospace',
+                fontSize: 12,
+                color: theme.colorScheme.onSurfaceVariant,
+              ),
+            ),
+          ),
+        ),
+    ];
+  }
+
+  /// Action hierarchy: refresh stays a secondary icon action; the primary
+  /// (filled) button is the test notification once the chain is operational,
+  /// otherwise re-registering IS the primary next step and the test action is
+  /// omitted (it could not succeed and the checklist explains why).
+  Widget _actions(PushStatusReport report) {
+    const spinner = SizedBox(
+      width: 16,
+      height: 16,
+      child: CircularProgressIndicator(strokeWidth: 2),
+    );
+    final ready = report.readyForTestNotification;
+    return Row(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        IconButton(
+          onPressed: _busy ? null : _load,
+          tooltip: 'Aktualisieren',
+          icon: const Icon(Icons.refresh),
+        ),
+        // OverflowBar stacks the buttons vertically on narrow screens instead
+        // of overflowing the row.
+        Expanded(
+          child: OverflowBar(
+            alignment: MainAxisAlignment.end,
+            overflowAlignment: OverflowBarAlignment.end,
+            spacing: 8,
+            overflowSpacing: 4,
+            children: [
+              if (ready) ...[
+                TextButton(
+                  onPressed: _busy ? null : _reRegister,
+                  child: const Text('Erneut registrieren'),
+                ),
+                FilledButton.icon(
+                  onPressed: _busy ? null : _sendTest,
+                  icon: _busy ? spinner : const Icon(Icons.send_outlined),
+                  label: const Text('Testbenachrichtigung'),
+                ),
+              ] else
+                FilledButton.icon(
+                  onPressed: _busy ? null : _reRegister,
+                  icon: _busy ? spinner : const Icon(Icons.sync),
+                  label: const Text('Erneut registrieren'),
+                ),
+            ],
+          ),
+        ),
+      ],
+    );
+  }
+
+  Widget _stateIcon(PushCheck state, ThemeData theme) {
+    switch (state) {
+      case PushCheck.ok:
+        return const Icon(Icons.check_circle_outline, color: Colors.green);
+      case PushCheck.fail:
+        return Icon(Icons.cancel_outlined, color: theme.colorScheme.error);
+      case PushCheck.unknown:
+        return Icon(
+          Icons.remove_circle_outline,
+          color: theme.colorScheme.onSurfaceVariant,
+        );
+    }
+  }
+}

lib/widget/user_avatar.dart

@@ -1,3 +1,4 @@
+import 'dart:async';
 import 'dart:collection';
 import 'dart:convert';
 import 'dart:typed_data';
@@ -8,6 +9,7 @@ import 'package:http/http.dart' as http;
 
 import '../model/account_data.dart';
 import '../model/endpoint_data.dart';
+import '../push/push_avatar.dart';
 
 class UserAvatar extends StatefulWidget {
   final String id;
@@ -86,6 +88,9 @@ void invalidateAvatarCache({String? id, bool? isGroup}) {
     final url = avatarUrl(id: id, isGroup: true);
     _resolvedAvatars.remove(url);
     _pendingAvatars.remove(url);
+    // Keep the push-notification disk cache in sync — it serves the same
+    // room avatar to the FCM background isolate.
+    unawaited(PushAvatarStore.evict(id));
   } else {
     // User avatars include the rendered size in the URL — drop every variant.
     final host = EndpointData().nextcloud().full();
@@ -242,11 +247,7 @@ class _UserAvatarState extends State<UserAvatar> {
       backgroundColor: theme.primaryColor,
       foregroundColor: Colors.white,
       child: ClipOval(
-        child: SizedBox(
-          width: radius * 2,
-          height: radius * 2,
-          child: content,
-        ),
+        child: SizedBox(width: radius * 2, height: radius * 2, child: content),
       ),
     );
   }

test/push/chat_thread_store_test.dart

@@ -0,0 +1,178 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:marianum_mobile/push/chat_thread_store.dart';
+
+ThreadMessage _msg(int nid, {String sender = 'Max', String text = 'hi'}) =>
+    ThreadMessage(nid: nid, sender: sender, text: text, timestampMs: nid);
+
+void main() {
+  group('appendThreadMessage', () {
+    test('appends in order', () {
+      var messages = <ThreadMessage>[];
+      messages = appendThreadMessage(messages, _msg(1));
+      messages = appendThreadMessage(messages, _msg(2));
+      expect(messages.map((m) => m.nid), [1, 2]);
+    });
+
+    test('caps the history, dropping the oldest', () {
+      var messages = <ThreadMessage>[];
+      for (var nid = 1; nid <= kChatThreadCap + 3; nid++) {
+        messages = appendThreadMessage(messages, _msg(nid));
+      }
+      expect(messages, hasLength(kChatThreadCap));
+      expect(messages.first.nid, 4);
+      expect(messages.last.nid, kChatThreadCap + 3);
+    });
+
+    test('a redelivered nid replaces the old entry instead of duplicating', () {
+      var messages = [_msg(1), _msg(2)];
+      messages = appendThreadMessage(messages, _msg(1, text: 'edited'));
+      expect(messages.map((m) => m.nid), [2, 1]);
+      expect(messages.last.text, 'edited');
+    });
+  });
+
+  group('threadAfterIncoming (dismiss/read reset)', () {
+    final existing = [_msg(1), _msg(2)];
+    final incoming = _msg(3);
+
+    test('active notification → new message stacks onto history', () {
+      final result = threadAfterIncoming(existing, incoming, true);
+      expect(result.map((m) => m.nid), [1, 2, 3]);
+    });
+
+    test('inactive notification → thread restarts with only the new one', () {
+      final result = threadAfterIncoming(existing, incoming, false);
+      expect(result.map((m) => m.nid), [3]);
+    });
+
+    test('unknown active state (probe failed) → stacks defensively', () {
+      final result = threadAfterIncoming(existing, incoming, null);
+      expect(result.map((m) => m.nid), [1, 2, 3]);
+    });
+
+    test('reset still honours the cap for a burst of messages', () {
+      final result = threadAfterIncoming(existing, incoming, false, cap: 1);
+      expect(result.map((m) => m.nid), [3]);
+    });
+  });
+
+  group('removeThreadNid', () {
+    test('removes only the matching message', () {
+      final remaining = removeThreadNid([_msg(1), _msg(2), _msg(3)], 2);
+      expect(remaining.map((m) => m.nid), [1, 3]);
+    });
+
+    test('deleting the last message empties the thread (caller cancels)', () {
+      final remaining = removeThreadNid([_msg(7)], 7);
+      expect(remaining, isEmpty);
+    });
+
+    test('unknown nid leaves the thread untouched', () {
+      final remaining = removeThreadNid([_msg(1)], 99);
+      expect(remaining.map((m) => m.nid), [1]);
+    });
+  });
+
+  group('conversationHeader', () {
+    test('1:1 chat (single sender, no room) gets no title', () {
+      final header = conversationHeader([
+        _msg(1, sender: 'Max'),
+        _msg(2, sender: 'Max'),
+      ]);
+      expect(header.conversationTitle, isNull);
+      expect(header.groupConversation, isFalse);
+    });
+
+    test('a known room name becomes the title exactly once', () {
+      final header = conversationHeader([
+        ThreadMessage(
+          nid: 1,
+          sender: 'Max',
+          text: 'hi',
+          timestampMs: 1,
+          roomName: 'Projektraum',
+        ),
+        _msg(2, sender: 'Max'),
+      ]);
+      expect(header.conversationTitle, 'Projektraum');
+      expect(header.groupConversation, isTrue);
+    });
+
+    test('multiple senders without room name fall back to last sender', () {
+      final header = conversationHeader([
+        _msg(1, sender: 'Max'),
+        _msg(2, sender: 'Anna'),
+      ]);
+      expect(header.conversationTitle, 'Anna');
+      expect(header.groupConversation, isTrue);
+    });
+  });
+
+  group('ThreadMessage roomName migration', () {
+    test('entries without roomName field read as null', () {
+      final restored = ThreadMessage.fromJson({
+        'nid': 1,
+        'sender': 'Max',
+        'text': 'hi',
+        'timestampMs': 5,
+      });
+      expect(restored.roomName, isNull);
+    });
+
+    test('roomName round-trips when present', () {
+      final restored = ThreadMessage.fromJson(
+        const ThreadMessage(
+          nid: 1,
+          sender: 'Max',
+          text: 'hi',
+          timestampMs: 5,
+          roomName: 'Raum',
+        ).toJson(),
+      );
+      expect(restored.roomName, 'Raum');
+    });
+  });
+
+  group('stable notification identity', () {
+    test('same token always yields the same 31-bit id', () {
+      final a = stableChatNotificationId('abc123');
+      expect(a, stableChatNotificationId('abc123'));
+      expect(a, greaterThanOrEqualTo(0));
+      expect(a, lessThanOrEqualTo(0x7fffffff));
+    });
+
+    test('different tokens yield different ids and tags', () {
+      expect(
+        stableChatNotificationId('abc123'),
+        isNot(stableChatNotificationId('xyz789')),
+      );
+      expect(chatNotificationTag('abc123'), 'talk_abc123');
+    });
+  });
+
+  group('ThreadMessage json', () {
+    test('round-trips', () {
+      final restored = ThreadMessage.fromJson(
+        ThreadMessage(
+          nid: 5,
+          sender: 'Max',
+          text: 'Hallo',
+          timestampMs: 1234,
+        ).toJson(),
+      );
+      expect(restored.nid, 5);
+      expect(restored.sender, 'Max');
+      expect(restored.text, 'Hallo');
+      expect(restored.timestampMs, 1234);
+    });
+  });
+
+  group('ChatThreadStore.docIdForToken', () {
+    test('url-safe tokens are used verbatim, others encoded', () {
+      expect(ChatThreadStore.docIdForToken('abc_1-2'), 'abc_1-2');
+      final encoded = ChatThreadStore.docIdForToken('a/b');
+      expect(encoded, isNot(contains('/')));
+      expect(encoded, ChatThreadStore.docIdForToken('a/b'));
+    });
+  });
+}

test/push/push_avatar_test.dart

@@ -0,0 +1,211 @@
+import 'dart:async';
+import 'dart:io';
+import 'dart:typed_data';
+import 'dart:ui' as ui;
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:http/http.dart' as http;
+import 'package:marianum_mobile/push/push_avatar.dart';
+
+final Uint8List _fakeBytes = Uint8List.fromList([
+  0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A, 1, 2, 3, //
+]);
+
+http.Response _imageResponse() => http.Response.bytes(
+  _fakeBytes,
+  200,
+  headers: {'content-type': 'image/png'},
+);
+
+/// Renders a solid 40×20 PNG via dart:ui — a real decodable source image.
+Future<Uint8List> _generatePng() async {
+  final recorder = ui.PictureRecorder();
+  final canvas = ui.Canvas(recorder);
+  canvas.drawRect(
+    const ui.Rect.fromLTWH(0, 0, 40, 20),
+    ui.Paint()..color = const ui.Color(0xFF993333),
+  );
+  final image = await recorder.endRecording().toImage(40, 20);
+  final data = await image.toByteData(format: ui.ImageByteFormat.png);
+  return data!.buffer.asUint8List();
+}
+
+void main() {
+  TestWidgetsFlutterBinding.ensureInitialized();
+
+  late Directory tempDir;
+
+  setUp(() async {
+    tempDir = await Directory.systemTemp.createTemp('push_avatar_test');
+  });
+
+  tearDown(() async {
+    await tempDir.delete(recursive: true);
+  });
+
+  PushAvatarStore store({
+    required Future<http.Response> Function(String chatToken) fetch,
+    Duration timeout = const Duration(seconds: 4),
+  }) => PushAvatarStore(
+    cacheDirProvider: () async => tempDir,
+    fetch: fetch,
+    fetchTimeout: timeout,
+  );
+
+  group('maskAvatarCircular', () {
+    test('output is a square PNG sized to the shorter edge', () async {
+      final source = await _generatePng();
+      final masked = await maskAvatarCircular(source);
+      expect(masked, isNotNull);
+      // PNG magic bytes.
+      expect(masked!.sublist(0, 8), [
+        0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A, //
+      ]);
+      final codec = await ui.instantiateImageCodec(masked);
+      final frame = await codec.getNextFrame();
+      expect(frame.image.width, 20);
+      expect(frame.image.height, 20);
+    });
+
+    test('is deterministic for identical input', () async {
+      final source = await _generatePng();
+      final a = await maskAvatarCircular(source);
+      final b = await maskAvatarCircular(source);
+      expect(a, isNotNull);
+      expect(a, equals(b));
+    });
+
+    test('undecodable bytes yield null (caller falls back to raw)', () async {
+      expect(await maskAvatarCircular(_fakeBytes), isNull);
+    });
+  });
+
+  group('roomAvatarIcon', () {
+    test('fetches, caches, and serves from cache afterwards', () async {
+      var fetchCount = 0;
+      final s = store(
+        fetch: (_) async {
+          fetchCount++;
+          return _imageResponse();
+        },
+      );
+
+      final first = await s.roomAvatarIcon('iconToken1');
+      // Fake bytes are undecodable → mask falls back to the raw bytes.
+      expect(first.icon, _fakeBytes);
+      expect(first.late, isNull);
+      expect(fetchCount, 1);
+
+      final second = await s.roomAvatarIcon('iconToken1');
+      expect(second.icon, _fakeBytes);
+      expect(fetchCount, 1);
+    });
+
+    test('svg placeholder is rejected and not cached', () async {
+      final s = store(
+        fetch: (_) async => http.Response(
+          '<svg xmlns="http://www.w3.org/2000/svg"/>',
+          200,
+          headers: {'content-type': 'image/svg+xml'},
+        ),
+      );
+      final lookup = await s.roomAvatarIcon('iconToken2');
+      expect(lookup.icon, isNull);
+      expect(lookup.late, isNull);
+      expect(File('${tempDir.path}/iconToken2').existsSync(), isFalse);
+    });
+
+    test('definitive fetch error yields no icon and no late future', () async {
+      final s = store(fetch: (_) async => throw const SocketException('down'));
+      final lookup = await s.roomAvatarIcon('iconToken3');
+      expect(lookup.icon, isNull);
+      expect(lookup.late, isNull);
+    });
+
+    test('fetch error falls back to a stale cache entry', () async {
+      final file = File('${tempDir.path}/iconToken4');
+      await file.writeAsBytes(_fakeBytes);
+      await file.setLastModified(
+        DateTime.now().subtract(const Duration(days: 20)),
+      );
+
+      final s = store(fetch: (_) async => throw const SocketException('down'));
+      final lookup = await s.roomAvatarIcon('iconToken4');
+      expect(lookup.icon, _fakeBytes);
+    });
+
+    test(
+      'timeout returns a late future that delivers exactly one result',
+      () async {
+        final completer = Completer<http.Response>();
+        var fetchCount = 0;
+        final s = store(
+          fetch: (_) {
+            fetchCount++;
+            return completer.future;
+          },
+          timeout: const Duration(milliseconds: 50),
+        );
+
+        final lookup = await s.roomAvatarIcon('iconToken5');
+        expect(lookup.icon, isNull);
+        expect(lookup.late, isNotNull);
+
+        completer.complete(_imageResponse());
+        final lateBytes = await lookup.late;
+        expect(lateBytes, _fakeBytes);
+
+        // The processed cache now serves directly — no second fetch.
+        final second = await s.roomAvatarIcon('iconToken5');
+        expect(second.icon, _fakeBytes);
+        expect(second.late, isNull);
+        expect(fetchCount, 1);
+      },
+    );
+
+    test('non-200 responses yield null', () async {
+      final s = store(fetch: (_) async => http.Response('gone', 404));
+      final lookup = await s.roomAvatarIcon('iconToken6');
+      expect(lookup.icon, isNull);
+      expect(lookup.late, isNull);
+    });
+  });
+
+  group('fileNameForToken / isFresh / looksLikeSvg', () {
+    test('url-safe tokens are used verbatim', () {
+      expect(PushAvatarStore.fileNameForToken('abc123_XY-z'), 'abc123_XY-z');
+    });
+
+    test('unsafe tokens are encoded deterministically and stay distinct', () {
+      final a = PushAvatarStore.fileNameForToken('a/b');
+      expect(a, PushAvatarStore.fileNameForToken('a/b'));
+      expect(a, isNot(PushAvatarStore.fileNameForToken('a.b')));
+      expect(RegExp(r'^[A-Za-z0-9_-]+$').hasMatch(a), isTrue);
+    });
+
+    test('isFresh boundary', () {
+      final now = DateTime(2026, 7, 5, 12);
+      expect(
+        PushAvatarStore.isFresh(now.subtract(const Duration(days: 13)), now),
+        isTrue,
+      );
+      expect(
+        PushAvatarStore.isFresh(
+          now.subtract(const Duration(days: 14, hours: 1)),
+          now,
+        ),
+        isFalse,
+      );
+    });
+
+    test('svg detection', () {
+      expect(
+        PushAvatarStore.looksLikeSvg(
+          Uint8List.fromList('  <svg xmlns="..."/>'.codeUnits),
+        ),
+        isTrue,
+      );
+      expect(PushAvatarStore.looksLikeSvg(_fakeBytes), isFalse);
+    });
+  });
+}

test/push/push_dual_registration_test.dart

@@ -0,0 +1,178 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:marianum_mobile/push/push_registration.dart';
+import 'package:marianum_mobile/push/push_registration_store.dart';
+import 'package:marianum_mobile/push/push_registration_type.dart';
+import 'package:marianum_mobile/push/push_secure_storage.dart';
+
+class _MemoryStorage implements FlutterSecureStorageLike {
+  final Map<String, String> values = {};
+
+  @override
+  Future<String?> read({required String key}) async => values[key];
+
+  @override
+  Future<void> write({required String key, required String? value}) async {
+    if (value == null) {
+      values.remove(key);
+    } else {
+      values[key] = value;
+    }
+  }
+
+  @override
+  Future<void> delete({required String key}) async => values.remove(key);
+}
+
+void main() {
+  group('talk user agents', () {
+    // Quoted from nextcloud/server lib/public/IRequest.php.
+    final uaTalkAndroid = RegExp(
+      r'^Mozilla/5\.0 \(Android\) Nextcloud-Talk v([^ ]*).*$',
+    );
+    final uaTalkIos = RegExp(
+      r'^Mozilla/5\.0 \(iOS\) Nextcloud-Talk v([^ ]*).*$',
+    );
+
+    test('android UA matches USER_AGENT_TALK_ANDROID', () {
+      expect(
+        uaTalkAndroid.hasMatch(PushRegistration.talkUserAgentAndroid),
+        isTrue,
+      );
+      expect(
+        uaTalkIos.hasMatch(PushRegistration.talkUserAgentAndroid),
+        isFalse,
+      );
+    });
+
+    test('ios UA matches USER_AGENT_TALK_IOS', () {
+      expect(uaTalkIos.hasMatch(PushRegistration.talkUserAgentIos), isTrue);
+      expect(
+        uaTalkAndroid.hasMatch(PushRegistration.talkUserAgentIos),
+        isFalse,
+      );
+    });
+  });
+
+  group('pushTokenVariant', () {
+    test('general uses the raw token, talk appends the suffix', () {
+      expect(pushTokenVariant('tok', PushRegistrationType.general), 'tok');
+      expect(pushTokenVariant('tok', PushRegistrationType.talk), 'tok#talk');
+    });
+
+    test('variants always differ (NC would delete same-hash siblings)', () {
+      const token = 'any-token';
+      expect(
+        pushTokenVariant(token, PushRegistrationType.general),
+        isNot(pushTokenVariant(token, PushRegistrationType.talk)),
+      );
+    });
+  });
+
+  group('PushRegistrationStore', () {
+    test('pre-dual entries are read as the general registration', () async {
+      final storage = _MemoryStorage();
+      // State written by a pre-dual app version (no type suffixes).
+      storage.values.addAll({
+        'push_device_identifier': 'legacy-device',
+        'push_server_public_key_pem': 'legacy-key',
+        'push_registered_fcm_token': 'legacy-token',
+        'push_registered_proxy_server': 'https://old/push-proxy/',
+        'push_registered_nc_base_url': 'https://cloud',
+        'push_last_registration_at': '2026-07-01T10:00:00.000',
+        'push_last_registration_error': '',
+      });
+      final store = PushRegistrationStore(storage);
+
+      expect(
+        await store.deviceIdentifier(PushRegistrationType.general),
+        'legacy-device',
+      );
+      expect(await store.isRegistered(PushRegistrationType.general), isTrue);
+      expect(
+        await store.registeredProxyServer(PushRegistrationType.general),
+        'https://old/push-proxy/',
+      );
+      expect(
+        await store.lastRegistrationAt(PushRegistrationType.general),
+        DateTime(2026, 7, 1, 10),
+      );
+
+      // The talk registration is genuinely absent — the self-heal adds it.
+      expect(await store.deviceIdentifier(PushRegistrationType.talk), isNull);
+      expect(await store.isRegistered(PushRegistrationType.talk), isFalse);
+    });
+
+    test('per-type values stay independent', () async {
+      final storage = _MemoryStorage();
+      final store = PushRegistrationStore(storage);
+
+      await store.save(
+        type: PushRegistrationType.general,
+        deviceIdentifier: 'dev-general',
+        serverPublicKeyPem: 'server-key',
+        fcmToken: 'token',
+        proxyServer: 'https://a/push-proxy/',
+        ncBaseUrl: 'https://cloud',
+      );
+      await store.save(
+        type: PushRegistrationType.talk,
+        deviceIdentifier: 'dev-talk',
+        serverPublicKeyPem: 'server-key',
+        fcmToken: 'token',
+        proxyServer: 'https://a/push-proxy/',
+        ncBaseUrl: 'https://cloud',
+      );
+      await store.saveLastRegistrationAttempt(
+        type: PushRegistrationType.talk,
+        at: DateTime(2026, 7, 5, 12),
+        error: 'HTTP 404',
+      );
+
+      expect(
+        await store.deviceIdentifier(PushRegistrationType.general),
+        'dev-general',
+      );
+      expect(
+        await store.deviceIdentifier(PushRegistrationType.talk),
+        'dev-talk',
+      );
+      // Shared server key: last write wins, both read the same value.
+      expect(await store.serverPublicKeyPem(), 'server-key');
+      expect(
+        await store.lastRegistrationError(PushRegistrationType.general),
+        isNull,
+      );
+      expect(
+        await store.lastRegistrationError(PushRegistrationType.talk),
+        'HTTP 404',
+      );
+    });
+
+    test('clear removes both registrations and shared keys', () async {
+      final storage = _MemoryStorage();
+      final store = PushRegistrationStore(storage);
+      for (final type in PushRegistrationType.values) {
+        await store.save(
+          type: type,
+          deviceIdentifier: 'dev',
+          serverPublicKeyPem: 'key',
+          fcmToken: 'token',
+          proxyServer: 'https://a/',
+          ncBaseUrl: 'https://cloud',
+        );
+        await store.saveLastRegistrationAttempt(
+          type: type,
+          at: DateTime(2026),
+          error: 'x',
+        );
+      }
+      await store.saveNativeAuthContext(
+        username: 'user',
+        baseUrl: 'https://cloud',
+      );
+
+      await store.clear();
+      expect(storage.values, isEmpty);
+    });
+  });
+}

test/push/push_reply_action_test.dart

@@ -0,0 +1,74 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:marianum_mobile/push/chat_thread_store.dart';
+import 'package:marianum_mobile/push/push_actions.dart';
+
+void main() {
+  group('PushActions.finishReply', () {
+    const token = 'chat1';
+    final thread = [
+      const ThreadMessage(nid: 1, sender: 'Max', text: 'Hi', timestampMs: 1),
+      const ThreadMessage(nid: 2, sender: 'Max', text: 'Da?', timestampMs: 2),
+    ];
+
+    test(
+      'successful reply removes the notification via chat cleanup',
+      () async {
+        var cleanups = 0;
+        var renders = 0;
+        var cancels = 0;
+        await PushActions.finishReply(
+          chatToken: token,
+          sent: true,
+          cleanupChat: (t) async {
+            expect(t, token);
+            cleanups++;
+          },
+          loadThread: (_) async => thread,
+          renderSilent: (_, _) async => renders++,
+          cancelNotification: (_) async => cancels++,
+        );
+        expect(cleanups, 1);
+        expect(renders, 0);
+        expect(cancels, 0);
+      },
+    );
+
+    test('failed reply re-renders the unchanged thread exactly once', () async {
+      var cleanups = 0;
+      var renders = 0;
+      List<ThreadMessage>? rendered;
+      await PushActions.finishReply(
+        chatToken: token,
+        sent: false,
+        cleanupChat: (_) async => cleanups++,
+        loadThread: (_) async => thread,
+        renderSilent: (t, messages) async {
+          expect(t, token);
+          renders++;
+          rendered = messages;
+        },
+        cancelNotification: (_) async => fail('must not cancel'),
+      );
+      expect(cleanups, 0);
+      expect(renders, 1);
+      // History unchanged — same messages, no self entry appended.
+      expect(rendered!.map((m) => m.nid), [1, 2]);
+    });
+
+    test(
+      'failed reply with empty history cancels to stop the spinner',
+      () async {
+        var cancels = 0;
+        await PushActions.finishReply(
+          chatToken: token,
+          sent: false,
+          cleanupChat: (_) async => fail('must not cleanup'),
+          loadThread: (_) async => const [],
+          renderSilent: (_, _) async => fail('nothing to render'),
+          cancelNotification: (_) async => cancels++,
+        );
+        expect(cancels, 1);
+      },
+    );
+  });
+}

test/push/push_status_test.dart

@@ -0,0 +1,214 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:marianum_mobile/push/push_status.dart';
+
+const _liveProxy = 'https://connect.marianum-fulda.de/push-proxy/';
+const _betaProxy = 'https://connect-beta.marianum-fulda.de/push-proxy/';
+
+PushTypeStatus _typeStatus({
+  bool nextcloudRegistered = true,
+  String? registeredNcBaseUrl = 'https://cloud.marianum-fulda.de',
+  String? registeredProxyServer = _liveProxy,
+  DateTime? lastRegistrationAt,
+  String? lastRegistrationError,
+}) => PushTypeStatus(
+  nextcloudRegistered: nextcloudRegistered,
+  registeredNcBaseUrl: registeredNcBaseUrl,
+  registeredProxyServer: registeredProxyServer,
+  lastRegistrationAt: lastRegistrationAt,
+  lastRegistrationError: lastRegistrationError,
+);
+
+PushStatusReport _report({
+  bool settingEnabled = true,
+  PushCheck osPermission = PushCheck.ok,
+  PushCheck serverCapability = PushCheck.ok,
+  bool appPasswordPresent = true,
+  bool talkAppPasswordPresent = true,
+  bool keypairPresent = true,
+  PushTypeStatus? general,
+  PushTypeStatus? talk,
+  String? currentProxyServer = _liveProxy,
+}) => PushStatusReport(
+  settingEnabled: settingEnabled,
+  osPermission: osPermission,
+  serverCapability: serverCapability,
+  appPasswordPresent: appPasswordPresent,
+  talkAppPasswordPresent: talkAppPasswordPresent,
+  keypairPresent: keypairPresent,
+  general: general ?? _typeStatus(),
+  talk: talk ?? _typeStatus(),
+  currentProxyServer: currentProxyServer,
+);
+
+PushStatusRow _row(List<PushStatusRow> rows, String label) =>
+    rows.singleWhere((r) => r.label == label);
+
+void main() {
+  group('buildPushStatusRows', () {
+    test('healthy chain shows nine ok rows in chain order', () {
+      final rows = buildPushStatusRows(_report());
+      expect(rows, hasLength(9));
+      expect(rows.map((r) => r.label), [
+        'Push-Benachrichtigungen aktiviert',
+        'Benachrichtigungsberechtigung',
+        'Server-Unterstützung',
+        'App-Passwörter',
+        'Geräteschlüssel',
+        'Nextcloud-Registrierung (Allgemein)',
+        'Nextcloud-Registrierung (Talk)',
+        'Connect-Registrierung (Allgemein)',
+        'Connect-Registrierung (Talk)',
+      ]);
+      expect(rows.every((r) => r.state == PushCheck.ok), isTrue);
+    });
+
+    test('disabled setting fails the first row with a hint', () {
+      final rows = buildPushStatusRows(_report(settingEnabled: false));
+      final row = _row(rows, 'Push-Benachrichtigungen aktiviert');
+      expect(row.state, PushCheck.fail);
+      expect(row.detail, contains('deaktiviert'));
+    });
+
+    test('unloaded capabilities show as unknown, not as failure', () {
+      final rows = buildPushStatusRows(
+        _report(serverCapability: PushCheck.unknown),
+      );
+      final row = _row(rows, 'Server-Unterstützung');
+      expect(row.state, PushCheck.unknown);
+      expect(row.detail, contains('noch nicht geladen'));
+    });
+
+    test('missing talk app password fails the password row and names it', () {
+      final rows = buildPushStatusRows(_report(talkAppPasswordPresent: false));
+      final row = _row(rows, 'App-Passwörter');
+      expect(row.state, PushCheck.fail);
+      expect(row.detail, contains('Talk-App-Passwort fehlt'));
+    });
+
+    test('registered rows carry their URL as detail', () {
+      final rows = buildPushStatusRows(_report());
+      expect(
+        _row(rows, 'Nextcloud-Registrierung (Allgemein)').detail,
+        'https://cloud.marianum-fulda.de',
+      );
+      expect(_row(rows, 'Connect-Registrierung (Talk)').detail, _liveProxy);
+    });
+
+    test('a broken talk registration fails only the talk rows', () {
+      final rows = buildPushStatusRows(
+        _report(
+          talk: _typeStatus(
+            nextcloudRegistered: false,
+            registeredProxyServer: null,
+          ),
+        ),
+      );
+      expect(
+        _row(rows, 'Nextcloud-Registrierung (Allgemein)').state,
+        PushCheck.ok,
+      );
+      expect(
+        _row(rows, 'Connect-Registrierung (Allgemein)').state,
+        PushCheck.ok,
+      );
+      expect(
+        _row(rows, 'Nextcloud-Registrierung (Talk)').state,
+        PushCheck.fail,
+      );
+      final talkConnect = _row(rows, 'Connect-Registrierung (Talk)');
+      expect(talkConnect.state, PushCheck.fail);
+      expect(talkConnect.detail, contains('ausstehend'));
+    });
+
+    test('proxy endpoint mismatch fails the affected row naming both URLs', () {
+      final report = _report(
+        talk: _typeStatus(registeredProxyServer: _liveProxy),
+        currentProxyServer: _betaProxy,
+        general: _typeStatus(registeredProxyServer: _betaProxy),
+      );
+      expect(report.proxyEndpointMismatch(report.talk), isTrue);
+      expect(report.proxyEndpointMismatch(report.general), isFalse);
+      final row = _row(
+        buildPushStatusRows(report),
+        'Connect-Registrierung (Talk)',
+      );
+      expect(row.state, PushCheck.fail);
+      expect(row.detail, contains('connect.marianum-fulda.de'));
+      expect(row.detail, contains('connect-beta.marianum-fulda.de'));
+    });
+
+    test('per-type registration errors fail only their own connect row', () {
+      final rows = buildPushStatusRows(
+        _report(talk: _typeStatus(lastRegistrationError: 'HTTP 404')),
+      );
+      expect(
+        _row(rows, 'Connect-Registrierung (Allgemein)').state,
+        PushCheck.ok,
+      );
+      final talkRow = _row(rows, 'Connect-Registrierung (Talk)');
+      expect(talkRow.state, PushCheck.fail);
+      expect(talkRow.detail, contains('fehlgeschlagen'));
+    });
+  });
+
+  group('PushStatusReport.readyForTestNotification', () {
+    test('test push only depends on the general chain', () {
+      // Test pushes are Connect direct pushes via the general registration —
+      // a broken talk registration must not disable the test action.
+      final report = _report(
+        talk: _typeStatus(
+          nextcloudRegistered: false,
+          registeredProxyServer: null,
+          lastRegistrationError: 'HTTP 404',
+        ),
+      );
+      expect(report.readyForTestNotification, isTrue);
+    });
+
+    test('denied OS permission wins over a complete registration', () {
+      expect(
+        _report(osPermission: PushCheck.fail).readyForTestNotification,
+        isFalse,
+      );
+    });
+
+    test('undetermined OS permission stays permissive', () {
+      expect(
+        _report(osPermission: PushCheck.unknown).readyForTestNotification,
+        isTrue,
+      );
+    });
+
+    test('missing general registration is not ready', () {
+      expect(
+        _report(
+          general: _typeStatus(nextcloudRegistered: false),
+        ).readyForTestNotification,
+        isFalse,
+      );
+      expect(
+        _report(
+          general: _typeStatus(registeredProxyServer: null),
+        ).readyForTestNotification,
+        isFalse,
+      );
+    });
+
+    test('general endpoint mismatch or failed attempt is not ready', () {
+      expect(
+        _report(
+          general: _typeStatus(registeredProxyServer: _liveProxy),
+          talk: _typeStatus(registeredProxyServer: _betaProxy),
+          currentProxyServer: _betaProxy,
+        ).readyForTestNotification,
+        isFalse,
+      );
+      expect(
+        _report(
+          general: _typeStatus(lastRegistrationError: 'HTTP 404'),
+        ).readyForTestNotification,
+        isFalse,
+      );
+    });
+  });
+}

test/push/talk_subject_parse_test.dart

@@ -0,0 +1,59 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:marianum_mobile/push/push_subject.dart';
+
+void main() {
+  group('parseTalkSubject', () {
+    test('1:1 chat: "{user}\\n{message}"', () {
+      final parsed = parseTalkSubject('Max Mustermann\nHallo zusammen');
+      expect(parsed.sender, 'Max Mustermann');
+      expect(parsed.roomName, isNull);
+      expect(parsed.text, 'Hallo zusammen');
+    });
+
+    test('group chat: "{user} in {call}\\n{message}" (de identical)', () {
+      final parsed = parseTalkSubject('Max in Projektraum\nHallo');
+      expect(parsed.sender, 'Max');
+      expect(parsed.roomName, 'Projektraum');
+      expect(parsed.text, 'Hallo');
+    });
+
+    test('sender containing " in " splits at the LAST separator', () {
+      final parsed = parseTalkSubject('Max in the Middle in Raum X\nHi');
+      expect(parsed.sender, 'Max in the Middle');
+      expect(parsed.roomName, 'Raum X');
+      expect(parsed.text, 'Hi');
+    });
+
+    test('legacy ": " separator still works as fallback', () {
+      final parsed = parseTalkSubject('Max: Hallo');
+      expect(parsed.sender, 'Max');
+      expect(parsed.roomName, isNull);
+      expect(parsed.text, 'Hallo');
+    });
+
+    test('legacy group form "Sender in Raum: msg"', () {
+      final parsed = parseTalkSubject('Max in Raum: Hallo');
+      expect(parsed.sender, 'Max');
+      expect(parsed.roomName, 'Raum');
+      expect(parsed.text, 'Hallo');
+    });
+
+    test('no separator falls back to a generic sender', () {
+      final parsed = parseTalkSubject(
+        'Max hat eine Nachricht in der Unterhaltung Raum gesendet',
+      );
+      expect(parsed.sender, 'Talk');
+      expect(parsed.roomName, isNull);
+      expect(
+        parsed.text,
+        'Max hat eine Nachricht in der Unterhaltung Raum gesendet',
+      );
+    });
+
+    test('multiline message keeps newlines after the first', () {
+      final parsed = parseTalkSubject('Max\nZeile 1\nZeile 2');
+      expect(parsed.sender, 'Max');
+      expect(parsed.text, 'Zeile 1\nZeile 2');
+    });
+  });
+}