diff --git a/lib/backend/modules/chats.dart b/lib/backend/modules/chats.dart
index 308b8a2..b1f4359 100644
--- a/lib/backend/modules/chats.dart
+++ b/lib/backend/modules/chats.dart
@@ -9,6 +9,7 @@ import '../../core/storage/app_database.dart';
 import '../../core/storage/token_storage.dart';
 import '../../core/utils/logger.dart';
 import '../api.dart';
+import 'folders.dart';
 import 'messages.dart' show ContactCache;
 
 Map<int, int> _parseParticipants(dynamic raw) {
@@ -78,6 +79,12 @@ class CachedChat {
 
   bool iAmAdmin(int myId) => owner == myId || admins.contains(myId);
 
+  bool get isMuted {
+    if (dontDisturbUntil == ChatsModule.muteOff) return false;
+    if (dontDisturbUntil < 0) return true;
+    return dontDisturbUntil > DateTime.now().millisecondsSinceEpoch;
+  }
+
   factory CachedChat.fromDbRow(Map<String, dynamic> row) => CachedChat(
     id: row['id'] as int,
     accountId: row['account_id'] as int,
@@ -140,20 +147,36 @@ class CachedChat {
 }
 
 class ChatsModule {
+  static const int muteOff = 0;
+  static const int muteForever = -1;
+
   static final ValueNotifier<int> chatsChanged = ValueNotifier(0);
   static void _bump() => chatsChanged.value = chatsChanged.value + 1;
 
   static final Set<int> _pendingContactUpdates = {};
   static Timer? _contactFlushTimer;
+  static Future<void>? _contactFlushFuture;
   static const _contactFlushDelay = Duration(milliseconds: 250);
 
   static void applyContactUpdate(int contactId) {
     _pendingContactUpdates.add(contactId);
-    _contactFlushTimer ??= Timer(_contactFlushDelay, _flushContactUpdates);
+    if (_contactFlushTimer != null) return;
+    if (_contactFlushFuture != null) return;
+    _contactFlushTimer = Timer(_contactFlushDelay, _kickFlush);
+  }
+
+  static void _kickFlush() {
+    _contactFlushTimer = null;
+    if (_contactFlushFuture != null) return;
+    _contactFlushFuture = _flushContactUpdates().whenComplete(() {
+      _contactFlushFuture = null;
+      if (_pendingContactUpdates.isNotEmpty) {
+        _contactFlushTimer ??= Timer(_contactFlushDelay, _kickFlush);
+      }
+    });
   }
 
   static Future<void> _flushContactUpdates() async {
-    _contactFlushTimer = null;
     if (_pendingContactUpdates.isEmpty) return;
     final ids = _pendingContactUpdates.toList();
     _pendingContactUpdates.clear();
@@ -161,18 +184,25 @@ class ChatsModule {
     final accountId = await TokenStorage.getActiveAccountId();
     if (accountId == null) return;
 
+    final dialogRows = await AppDatabase.loadDialogChats(accountId);
+    final byParticipant = <int, List<Map<String, dynamic>>>{};
+    for (final row in dialogRows) {
+      final cached = CachedChat.fromDbRow(row);
+      for (final pid in cached.participants.keys) {
+        if (pid == accountId) continue;
+        byParticipant.putIfAbsent(pid, () => []).add(row);
+      }
+    }
+
     final updates = <Map<String, dynamic>>[];
     for (final contactId in ids) {
       final name = ContactCache.get(contactId);
       if (name == null) continue;
       final avatar = ContactCache.getAvatar(contactId);
       final options = ContactCache.getOptions(contactId) ?? const <String>{};
-
-      final rows = await AppDatabase.findDialogChatsByParticipant(
-        accountId,
-        contactId,
-      );
-      for (final row in rows) {
+      final affected = byParticipant[contactId];
+      if (affected == null) continue;
+      for (final row in affected) {
         final cached = CachedChat.fromDbRow(row);
         final sameTitle = cached.title == name;
         final sameAvatar = (cached.iconUrl ?? '') == (avatar ?? '');
@@ -194,12 +224,15 @@ class ChatsModule {
 
   static Future<CachedChat?> cacheServerChat(
     Map<dynamic, dynamic> chat,
-    int accountId,
-  ) async {
+    int accountId, {
+    Map<int, CachedChat>? preloadedExisting,
+  }) async {
     final cachedAt = DateTime.now().millisecondsSinceEpoch;
     final id = chat['id'];
     Map<int, CachedChat> existing = const {};
-    if (id is int) {
+    if (preloadedExisting != null) {
+      existing = preloadedExisting;
+    } else if (id is int) {
       final rows = await AppDatabase.loadChat(accountId, id);
       if (rows.isNotEmpty) {
         existing = {id: CachedChat.fromDbRow(rows.first)};
@@ -219,11 +252,40 @@ class ChatsModule {
       logger.w('cacheServerChat: parse returned null for chat=${chat['id']}');
       return null;
     }
+    final ex = existing[parsed.id];
+    if (ex != null && _sameContent(ex, parsed)) {
+      return parsed;
+    }
     await AppDatabase.saveChats([parsed.toDbRow()]);
     _bump();
     return parsed;
   }
 
+  static bool _sameContent(CachedChat a, CachedChat b) {
+    if (a.title != b.title) return false;
+    if (a.iconUrl != b.iconUrl) return false;
+    if (a.owner != b.owner) return false;
+    if (a.dontDisturbUntil != b.dontDisturbUntil) return false;
+    if (a.favIndex != b.favIndex) return false;
+    if (a.lastMsgId != b.lastMsgId) return false;
+    if (a.lastMsgTime != b.lastMsgTime) return false;
+    if (a.lastMsgText != b.lastMsgText) return false;
+    if (a.lastMsgSenderId != b.lastMsgSenderId) return false;
+    if (a.unreadCount != b.unreadCount) return false;
+    if (a.lastEventTime != b.lastEventTime) return false;
+    if (a.isOnline != b.isOnline) return false;
+    if (a.seenTime != b.seenTime) return false;
+    if (a.admins.length != b.admins.length) return false;
+    if (!a.admins.containsAll(b.admins)) return false;
+    if (a.options.length != b.options.length) return false;
+    if (!a.options.containsAll(b.options)) return false;
+    if (a.participants.length != b.participants.length) return false;
+    for (final e in a.participants.entries) {
+      if (b.participants[e.key] != e.value) return false;
+    }
+    return true;
+  }
+
   /// Парсит и кэширует чаты из payload opcode 19.
   ///
   /// Для диалогов разрезолвит имя и аватар из списка [contacts] того же
@@ -563,6 +625,95 @@ class ChatsModule {
     return packet.isOk;
   }
 
+  static Future<String?> togglePin(
+    Api api, {
+    required List<int> chatIds,
+    required bool pin,
+  }) async {
+    if (chatIds.isEmpty) return null;
+    try {
+      final accountId = await TokenStorage.getActiveAccountId();
+      if (accountId == null) return 'Нет активного аккаунта';
+      final folders = await FoldersModule.loadFolders(accountId);
+      final allFolder = folders.firstWhere(
+        FoldersModule.isAllChatsFolder,
+        orElse: () => folders.isEmpty
+            ? throw StateError('Папка "Все" не найдена')
+            : folders.first,
+      );
+
+      final favorites = List<int>.from(allFolder.favorites ?? const []);
+      if (pin) {
+        for (final id in chatIds) {
+          if (!favorites.contains(id)) favorites.add(id);
+        }
+      } else {
+        favorites.removeWhere((id) => chatIds.contains(id));
+      }
+
+      await FoldersModule.setFolderFavorites(api, accountId, allFolder, favorites);
+
+      final existingRows = await AppDatabase.loadChatsByIds(accountId, chatIds);
+      final updates = <Map<String, dynamic>>[];
+      for (final row in existingRows) {
+        final id = row['id'] as int;
+        final isFav = favorites.contains(id);
+        final currentFav = row['fav_index'] as int?;
+        final newFav = isFav
+            ? ((currentFav ?? 0) > 0 ? currentFav : favorites.indexOf(id) + 1)
+            : 0;
+        if (currentFav == newFav) continue;
+        final newRow = Map<String, dynamic>.from(row);
+        newRow['fav_index'] = newFav;
+        updates.add(newRow);
+      }
+      if (updates.isNotEmpty) {
+        await AppDatabase.saveChats(updates);
+        _bump();
+      }
+      return null;
+    } on PacketError catch (e) {
+      logger.w('togglePin: ${e.message}');
+      return e.message;
+    } catch (e) {
+      logger.w('togglePin: $e');
+      return 'Не удалось изменить закрепление';
+    }
+  }
+
+  static Future<String?> setChatMute(
+    Api api, {
+    required int chatId,
+    required int dontDisturbUntil,
+  }) async {
+    try {
+      await api.sendRequest(Opcode.config, {
+        'settings': {
+          'chats': {
+            chatId: {'dontDisturbUntil': dontDisturbUntil},
+          },
+        },
+      });
+      final accountId = await TokenStorage.getActiveAccountId();
+      if (accountId != null) {
+        final rows = await AppDatabase.loadChat(accountId, chatId);
+        if (rows.isNotEmpty) {
+          final row = Map<String, dynamic>.from(rows.first);
+          row['dont_disturb_until'] = dontDisturbUntil;
+          await AppDatabase.saveChats([row]);
+          _bump();
+        }
+      }
+      return null;
+    } on PacketError catch (e) {
+      logger.w('setChatMute $chatId: ${e.message}');
+      return e.message;
+    } catch (e) {
+      logger.w('setChatMute $chatId: $e');
+      return 'Не удалось изменить уведомления';
+    }
+  }
+
   static Future<String?> deleteChat(
     Api api, {
     required int chatId,
@@ -605,10 +756,19 @@ class ChatsModule {
       if (list is! List) return const [];
       final accountId = await TokenStorage.getActiveAccountId();
       if (accountId == null) return const [];
+      final existingRows = await AppDatabase.loadChatsByIds(accountId, chatIds);
+      final preloadedExisting = {
+        for (final row in existingRows)
+          row['id'] as int: CachedChat.fromDbRow(row),
+      };
       final out = <CachedChat>[];
       for (final c in list) {
         if (c is Map) {
-          final cached = await cacheServerChat(c, accountId);
+          final cached = await cacheServerChat(
+            c,
+            accountId,
+            preloadedExisting: preloadedExisting,
+          );
           if (cached != null) out.add(cached);
         }
       }
diff --git a/lib/backend/modules/folders.dart b/lib/backend/modules/folders.dart
index 7f66fd2..b2856d8 100644
--- a/lib/backend/modules/folders.dart
+++ b/lib/backend/modules/folders.dart
@@ -179,6 +179,57 @@ class FoldersModule {
     await markFoldersListReady(accountId);
   }
 
+  static Future<ChatFolder?> setFolderFavorites(
+    Api api,
+    int accountId,
+    ChatFolder folder,
+    List<int> favorites,
+  ) async {
+    final packet = await api.sendRequest(Opcode.foldersUpdate, {
+      'id': folder.id,
+      'title': folder.title,
+      'include': folder.include ?? const [],
+      'favorites': favorites,
+      'filters': folder.filters,
+      'options': folder.options ?? const [],
+    });
+    if (packet.isError) {
+      throw PacketError(messageFromErrorPayload(packet.payload));
+    }
+    final data = packet.payload;
+    if (data is! Map) return null;
+    final folderJson = data['folder'];
+    if (folderJson is! Map) return null;
+    final updated = ChatFolder.fromJson(
+      folderJson is Map<String, dynamic>
+          ? folderJson
+          : Map<String, dynamic>.from(folderJson),
+    );
+
+    final currentRaw = await AppDatabase.getSyncValue(accountId, _syncKey);
+    final snapshot = (currentRaw != null && currentRaw.isNotEmpty)
+        ? jsonDecode(currentRaw) as Map<String, dynamic>
+        : <String, dynamic>{};
+    final existing = (snapshot['folders'] as List?)
+            ?.map((e) {
+              final m = e is Map<String, dynamic>
+                  ? e
+                  : Map<String, dynamic>.from(e as Map);
+              return ChatFolder.fromJson(m);
+            })
+            .toList() ??
+        <ChatFolder>[];
+    final idx = existing.indexWhere((f) => f.id == updated.id);
+    if (idx >= 0) {
+      existing[idx] = updated;
+    } else {
+      existing.add(updated);
+    }
+    final order = snapshot['foldersOrder'] as List<dynamic>?;
+    await _persist(accountId, existing, order);
+    return updated;
+  }
+
   static Future<void> syncFromServer(Api api, int accountId) async {
     try {
       final packet = await api.sendRequest(Opcode.foldersGet, {
diff --git a/lib/core/config/app_bubble_behavior.dart b/lib/core/config/app_bubble_behavior.dart
new file mode 100644
index 0000000..9ea84cf
--- /dev/null
+++ b/lib/core/config/app_bubble_behavior.dart
@@ -0,0 +1,37 @@
+import 'package:flutter/foundation.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+enum BubbleBehavior { mutable, immutable }
+
+class AppBubbleBehavior {
+  static const prefKey = 'app_bubble_behavior';
+  static final ValueNotifier<BubbleBehavior> current = ValueNotifier(
+    BubbleBehavior.mutable,
+  );
+
+  static Future<BubbleBehavior> load() async {
+    final prefs = await SharedPreferences.getInstance();
+    final val = prefs.getString(prefKey);
+    return _parse(val);
+  }
+
+  static Future<void> save(BubbleBehavior behavior) async {
+    current.value = behavior;
+    final prefs = await SharedPreferences.getInstance();
+    await prefs.setString(prefKey, behavior.name);
+  }
+
+  static BubbleBehavior _parse(String? val) {
+    if (val == BubbleBehavior.immutable.name) return BubbleBehavior.immutable;
+    return BubbleBehavior.mutable;
+  }
+
+  static String label(BubbleBehavior behavior) {
+    switch (behavior) {
+      case BubbleBehavior.mutable:
+        return 'Изменяемая';
+      case BubbleBehavior.immutable:
+        return 'Неизменяемая';
+    }
+  }
+}
diff --git a/lib/core/storage/app_database.dart b/lib/core/storage/app_database.dart
index 06dab07..3b61d69 100644
--- a/lib/core/storage/app_database.dart
+++ b/lib/core/storage/app_database.dart
@@ -471,15 +471,26 @@ class AppDatabase {
     );
   }
 
-  static Future<List<Map<String, dynamic>>> findDialogChatsByParticipant(
-    int accountId,
-    int contactId,
-  ) async {
+  static Future<List<Map<String, dynamic>>> loadDialogChats(int accountId) async {
     final db = await _instance;
     return db.query(
       'chats_cache',
-      where: "account_id = ? AND type = 'DIALOG' AND participants LIKE ?",
-      whereArgs: [accountId, '%"$contactId":%'],
+      where: "account_id = ? AND type = 'DIALOG'",
+      whereArgs: [accountId],
+    );
+  }
+
+  static Future<List<Map<String, dynamic>>> loadChatsByIds(
+    int accountId,
+    List<int> ids,
+  ) async {
+    if (ids.isEmpty) return const [];
+    final db = await _instance;
+    final placeholders = List.filled(ids.length, '?').join(',');
+    return db.query(
+      'chats_cache',
+      where: 'account_id = ? AND id IN ($placeholders)',
+      whereArgs: [accountId, ...ids],
     );
   }
 
diff --git a/lib/core/utils/bubble_radius.dart b/lib/core/utils/bubble_radius.dart
new file mode 100644
index 0000000..7c45ca3
--- /dev/null
+++ b/lib/core/utils/bubble_radius.dart
@@ -0,0 +1,81 @@
+import 'package:flutter/widgets.dart';
+
+import '../config/app_bubble_behavior.dart';
+import '../config/app_bubble_shape.dart';
+
+const double kBubbleBigRadius = 20;
+const double kBubbleSmallRadius = 4;
+
+const Radius _big = Radius.circular(kBubbleBigRadius);
+const Radius _small = Radius.circular(kBubbleSmallRadius);
+
+BorderRadius computeBubbleRadius({
+  required bool isMe,
+  required bool isTop,
+  required bool isBottom,
+  required BubbleStyle style,
+  required BubbleBehavior behavior,
+  bool hasPhotoWithCaption = false,
+  bool hasMultiplePhotosNoCaption = false,
+}) {
+  final isSingle = isTop && isBottom;
+
+  if (hasPhotoWithCaption && (isTop || isBottom)) {
+    return BorderRadius.only(
+      topLeft: _big,
+      topRight: _big,
+      bottomLeft: isMe ? _big : _small,
+      bottomRight: _small,
+    );
+  }
+
+  if (hasMultiplePhotosNoCaption && isBottom) {
+    return BorderRadius.only(
+      topLeft: isMe ? _big : _small,
+      topRight: _small,
+      bottomLeft: isMe ? _big : _small,
+      bottomRight: isMe ? _small : _big,
+    );
+  }
+
+  final base = style == BubbleStyle.desktop ? _small : _big;
+  Radius tl = base, tr = base, bl = base, br = base;
+
+  if (behavior == BubbleBehavior.immutable || isSingle) {
+    return BorderRadius.only(
+      topLeft: tl,
+      topRight: tr,
+      bottomLeft: bl,
+      bottomRight: br,
+    );
+  }
+
+  if (isTop) {
+    if (isMe) {
+      br = _small;
+    } else {
+      bl = _small;
+    }
+  } else if (isBottom) {
+    if (isMe) {
+      tr = _small;
+    } else {
+      tl = _small;
+    }
+  } else {
+    if (isMe) {
+      tr = _small;
+      br = _small;
+    } else {
+      tl = _small;
+      bl = _small;
+    }
+  }
+
+  return BorderRadius.only(
+    topLeft: tl,
+    topRight: tr,
+    bottomLeft: bl,
+    bottomRight: br,
+  );
+}
diff --git a/lib/frontend/screens/chats/chat_list_screen.dart b/lib/frontend/screens/chats/chat_list_screen.dart
index 1597438..60b4d53 100644
--- a/lib/frontend/screens/chats/chat_list_screen.dart
+++ b/lib/frontend/screens/chats/chat_list_screen.dart
@@ -183,11 +183,10 @@ class _ChatListScreenState extends State<ChatListScreen>
     return _DeleteKind.blocked;
   }
 
-  _DeleteKind? _selectionDeleteCategory() {
+  _DeleteKind? _selectionDeleteCategoryFor(List<CachedChat> selected) {
     if (_sessionState != SessionState.online) return null;
     final myId = _profile?.id;
     if (myId == null) return null;
-    final selected = _selectedChatObjects();
     if (selected.isEmpty) return null;
     final cats = selected.map((c) => _categorizeChat(c, myId)).toSet();
     if (cats.contains(_DeleteKind.blocked)) return null;
@@ -195,6 +194,47 @@ class _ChatListScreenState extends State<ChatListScreen>
     return cats.single;
   }
 
+  Future<void> _onPinTap() async {
+    final selected = _selectedChatObjects();
+    if (selected.isEmpty) return;
+    final anyPinned = selected.any((c) => (c.favIndex ?? 0) > 0);
+    final err = await ChatsModule.togglePin(
+      api,
+      chatIds: selected.map((c) => c.id).toList(),
+      pin: !anyPinned,
+    );
+    if (!mounted) return;
+    if (err != null) showCustomNotification(context, err);
+    _clearSelection();
+  }
+
+  Future<void> _onMuteTap() async {
+    final selected = _selectedChatObjects();
+    if (selected.isEmpty) return;
+    final anyMuted = selected.any((c) => c.isMuted);
+    final targetDDU = anyMuted ? ChatsModule.muteOff : ChatsModule.muteForever;
+
+    final errors = <String>[];
+    for (final c in selected) {
+      final err = await ChatsModule.setChatMute(
+        api,
+        chatId: c.id,
+        dontDisturbUntil: targetDDU,
+      );
+      if (err != null) errors.add(err);
+    }
+    if (!mounted) return;
+    if (errors.isNotEmpty) {
+      showCustomNotification(
+        context,
+        errors.length == 1
+            ? errors.first
+            : 'Не удалось изменить ${errors.length} чат(ов): ${errors.first}',
+      );
+    }
+    _clearSelection();
+  }
+
   Future<void> _onDeleteTap() async {
     final selectedBefore = _selectedChatObjects();
     if (selectedBefore.isEmpty) return;
@@ -1328,7 +1368,7 @@ class _ChatListScreenState extends State<ChatListScreen>
                     avatar ?? "",
                     isOnline: chat.isOnline,
                     unreadCount: chat.unreadCount,
-                    isMuted: chat.dontDisturbUntil > 0,
+                    isMuted: chat.isMuted,
                     isVerified: isVerified,
                     isPinned: isPinned,
                     chatType: "DIALOG",
@@ -1358,7 +1398,7 @@ class _ChatListScreenState extends State<ChatListScreen>
                         : '',
                     isOnline: chat.isOnline,
                     unreadCount: chat.unreadCount,
-                    isMuted: chat.dontDisturbUntil > 0,
+                    isMuted: chat.isMuted,
                     isVerified: chat.isOfficial,
                     isPinned: isPinned,
                     chatType: chat.type,
@@ -1803,37 +1843,53 @@ class _ChatListScreenState extends State<ChatListScreen>
                         ),
                       ],
                     ),
-                    child: Row(
-                      children: [
-                        IconButton(
-                          icon: Icon(Symbols.arrow_back, color: cs.onSurface),
-                          onPressed: _clearSelection,
-                        ),
-                        const SizedBox(width: 8),
-                        Text(
-                          _selectedChats.length.toString(),
-                          style: TextStyle(
-                            color: cs.onSurface,
-                            fontSize: 18,
-                            fontWeight: FontWeight.w600,
-                          ),
-                        ),
-                        const Spacer(),
-                        if (_selectionDeleteCategory() != null)
+                    child: Builder(builder: (_) {
+                      final selected = _selectedChatObjects();
+                      final deleteCategory = _selectionDeleteCategoryFor(selected);
+                      final anyMuted = selected.any((c) => c.isMuted);
+                      final anyPinned = selected.any((c) => (c.favIndex ?? 0) > 0);
+                      return Row(
+                        children: [
                           IconButton(
-                            icon: Icon(Symbols.delete, color: cs.onSurface),
-                            onPressed: _onDeleteTap,
+                            icon: Icon(Symbols.arrow_back, color: cs.onSurface),
+                            onPressed: _clearSelection,
                           ),
-                        IconButton(
-                          icon: Icon(Symbols.archive, color: cs.onSurface),
-                          onPressed: () {},
-                        ),
-                        IconButton(
-                          icon: Icon(Symbols.volume_off, color: cs.onSurface),
-                          onPressed: () {},
-                        ),
-                      ],
-                    ),
+                          const SizedBox(width: 8),
+                          Text(
+                            _selectedChats.length.toString(),
+                            style: TextStyle(
+                              color: cs.onSurface,
+                              fontSize: 18,
+                              fontWeight: FontWeight.w600,
+                            ),
+                          ),
+                          const Spacer(),
+                          if (deleteCategory != null)
+                            IconButton(
+                              icon: Icon(Symbols.delete, color: cs.onSurface),
+                              onPressed: _onDeleteTap,
+                            ),
+                          IconButton(
+                            icon: Icon(Symbols.archive, color: cs.onSurface),
+                            onPressed: () {},
+                          ),
+                          IconButton(
+                            icon: Icon(
+                              anyPinned ? Symbols.keep_off : Symbols.keep,
+                              color: cs.onSurface,
+                            ),
+                            onPressed: selected.isEmpty ? null : _onPinTap,
+                          ),
+                          IconButton(
+                            icon: Icon(
+                              anyMuted ? Symbols.volume_up : Symbols.volume_off,
+                              color: cs.onSurface,
+                            ),
+                            onPressed: selected.isEmpty ? null : _onMuteTap,
+                          ),
+                        ],
+                      );
+                    }),
                   ),
                 ),
               ],
diff --git a/lib/frontend/screens/profile/appearance_screen.dart b/lib/frontend/screens/profile/appearance_screen.dart
index c74aaaf..09c96fd 100644
--- a/lib/frontend/screens/profile/appearance_screen.dart
+++ b/lib/frontend/screens/profile/appearance_screen.dart
@@ -4,7 +4,9 @@ import 'package:flutter/material.dart';
 import 'package:m3e_collection/m3e_collection.dart';
 import 'package:material_symbols_icons/symbols.dart';
 
+import '../../../core/config/app_bubble_behavior.dart';
 import '../../../core/config/app_bubble_shape.dart';
+import '../../../core/utils/bubble_radius.dart';
 import '../../../core/utils/haptics.dart';
 import '../../../main.dart';
 
@@ -70,6 +72,11 @@ class _AppearanceScreenState extends State<AppearanceScreen> {
     AppBubbleShape.save(style);
   }
 
+  void _onBehaviorChanged(BubbleBehavior behavior) {
+    Haptics.selection();
+    AppBubbleBehavior.save(behavior);
+  }
+
   @override
   Widget build(BuildContext context) {
     final cs = Theme.of(context).colorScheme;
@@ -98,6 +105,8 @@ class _AppearanceScreenState extends State<AppearanceScreen> {
             ),
             const SizedBox(height: 12),
             _BubbleShapeCard(onChanged: _onStyleChanged),
+            const SizedBox(height: 12),
+            _BubbleBehaviorCard(onChanged: _onBehaviorChanged),
           ],
         ),
       ),
@@ -168,55 +177,85 @@ class _PreviewSectionState extends State<_PreviewSection> {
 class _ChatPreview extends StatelessWidget {
   const _ChatPreview();
 
+  static const _messages = <_PreviewMsg>[
+    _PreviewMsg('Привет!', true, true, false),
+    _PreviewMsg('Как тебе?', true, false, true),
+    _PreviewMsg('Привет!', false, true, false),
+    _PreviewMsg('хм...', false, false, false),
+    _PreviewMsg('Вполне неплохо!', false, false, true),
+  ];
+
+  BorderRadius _radiusFor(
+    _PreviewMsg msg,
+    BubbleStyle style,
+    BubbleBehavior behavior,
+  ) {
+    return computeBubbleRadius(
+      isMe: msg.isMe,
+      isTop: msg.isTop,
+      isBottom: msg.isBottom,
+      style: style,
+      behavior: behavior,
+    );
+  }
+
   @override
   Widget build(BuildContext context) {
     final cs = Theme.of(context).colorScheme;
 
-    return ValueListenableBuilder<BubbleStyle>(
-      valueListenable: AppBubbleShape.current,
-      builder: (context, style, _) => Container(
-        decoration: BoxDecoration(
-          color: cs.surfaceContainerLow,
-          borderRadius: BorderRadius.circular(28),
-          border: Border.all(color: cs.outlineVariant.withValues(alpha: 0.5)),
-        ),
-        padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 20),
-        child: Column(
-          crossAxisAlignment: CrossAxisAlignment.stretch,
-          children: [
-            _PreviewBubble(text: 'Как тебе?', isMe: true, style: style),
-            const SizedBox(height: 6),
-            _PreviewBubble(text: 'отлично выглядит!', isMe: false, style: style),
-          ],
-        ),
+    return ListenableBuilder(
+      listenable: Listenable.merge(
+        [AppBubbleShape.current, AppBubbleBehavior.current],
       ),
+      builder: (context, _) {
+        final style = AppBubbleShape.current.value;
+        final behavior = AppBubbleBehavior.current.value;
+        return Container(
+          decoration: BoxDecoration(
+            color: cs.surfaceContainerLow,
+            borderRadius: BorderRadius.circular(28),
+            border: Border.all(color: cs.outlineVariant.withValues(alpha: 0.5)),
+          ),
+          padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 20),
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.stretch,
+            children: [
+              for (var i = 0; i < _messages.length; i++) ...[
+                if (i > 0)
+                  SizedBox(height: _messages[i].isTop ? 8 : 2),
+                _PreviewBubble(
+                  text: _messages[i].text,
+                  isMe: _messages[i].isMe,
+                  radius: _radiusFor(_messages[i], style, behavior),
+                ),
+              ],
+            ],
+          ),
+        );
+      },
     );
   }
 }
 
+class _PreviewMsg {
+  final String text;
+  final bool isMe;
+  final bool isTop;
+  final bool isBottom;
+  const _PreviewMsg(this.text, this.isMe, this.isTop, this.isBottom);
+}
+
 class _PreviewBubble extends StatelessWidget {
   final String text;
   final bool isMe;
-  final BubbleStyle style;
+  final BorderRadius radius;
 
   const _PreviewBubble({
     required this.text,
     required this.isMe,
-    required this.style,
+    required this.radius,
   });
 
-  BorderRadius get _radius {
-    const big = Radius.circular(20);
-    const small = Radius.circular(4);
-    final outside = style == BubbleStyle.mobile ? big : small;
-    return BorderRadius.only(
-      topLeft: isMe ? outside : big,
-      topRight: isMe ? big : outside,
-      bottomLeft: isMe ? outside : big,
-      bottomRight: isMe ? big : outside,
-    );
-  }
-
   @override
   Widget build(BuildContext context) {
     final cs = Theme.of(context).colorScheme;
@@ -230,7 +269,7 @@ class _PreviewBubble extends StatelessWidget {
       child: Container(
         constraints: const BoxConstraints(maxWidth: 220),
         padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 10),
-        decoration: BoxDecoration(color: bg, borderRadius: _radius),
+        decoration: BoxDecoration(color: bg, borderRadius: radius),
         child: Text(
           text,
           style: TextStyle(color: fg, fontSize: 15, height: 1.3),
@@ -444,6 +483,67 @@ class _BubbleShapeCard extends StatelessWidget {
   }
 }
 
+class _BubbleBehaviorCard extends StatelessWidget {
+  final ValueChanged<BubbleBehavior> onChanged;
+
+  const _BubbleBehaviorCard({required this.onChanged});
+
+  @override
+  Widget build(BuildContext context) {
+    final cs = Theme.of(context).colorScheme;
+
+    return Material(
+      color: cs.surfaceContainerHigh,
+      borderRadius: BorderRadius.circular(28),
+      child: Padding(
+        padding: const EdgeInsets.fromLTRB(20, 18, 20, 20),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Text(
+              'Поведение сообщения',
+              style: TextStyle(
+                color: cs.onSurface,
+                fontSize: 16,
+                fontWeight: FontWeight.w700,
+              ),
+            ),
+            const SizedBox(height: 4),
+            Text(
+              'Меняется ли форма пузыря по соседям в группе',
+              style: TextStyle(color: cs.onSurfaceVariant, fontSize: 13),
+            ),
+            const SizedBox(height: 16),
+            ValueListenableBuilder<BubbleBehavior>(
+              valueListenable: AppBubbleBehavior.current,
+              builder: (context, current, _) {
+                return SegmentedButton<BubbleBehavior>(
+                  segments: const [
+                    ButtonSegment(
+                      value: BubbleBehavior.mutable,
+                      label: Text('Изменяемая'),
+                      icon: Icon(Symbols.auto_fix),
+                    ),
+                    ButtonSegment(
+                      value: BubbleBehavior.immutable,
+                      label: Text('Неизменяемая'),
+                      icon: Icon(Symbols.lock),
+                    ),
+                  ],
+                  selected: {current},
+                  onSelectionChanged: (set) {
+                    if (set.isNotEmpty) onChanged(set.first);
+                  },
+                );
+              },
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
 class _HueStripPicker extends StatelessWidget {
   final Color color;
   final ValueChanged<Color> onChanged;
diff --git a/lib/frontend/widgets/message_bubble.dart b/lib/frontend/widgets/message_bubble.dart
index cc8c460..dfe82b3 100644
--- a/lib/frontend/widgets/message_bubble.dart
+++ b/lib/frontend/widgets/message_bubble.dart
@@ -3,7 +3,9 @@ import 'package:flutter/material.dart';
 import 'package:komet/main.dart';
 import 'package:material_symbols_icons/symbols.dart';
 import '../../backend/modules/messages.dart';
+import '../../core/config/app_bubble_behavior.dart';
 import '../../core/config/app_bubble_shape.dart';
+import '../../core/utils/bubble_radius.dart';
 import '../../core/utils/haptics.dart';
 import '../../models/attachment.dart';
 
@@ -196,71 +198,21 @@ class MessageBubble extends StatelessWidget {
 
   BorderRadius _borderRadiusFor(
     BubbleStyle bubbleStyle,
+    BubbleBehavior bubbleBehavior,
     BubbleShape shape,
     bool hasPhotoWithCaption,
     bool hasMultiplePhotosNoCaption,
   ) {
-    final outsideRadius =
-        bubbleStyle == BubbleStyle.mobile ? _bigRadius : _smallRadius;
-
-    if (hasPhotoWithCaption &&
-        (shape == BubbleShape.singleTop ||
-            shape == BubbleShape.singleMiddle ||
-            shape == BubbleShape.singleBottom)) {
-      return BorderRadius.only(
-        topLeft: _bigRadius,
-        topRight: _bigRadius,
-        bottomLeft: isMe ? _bigRadius : _smallRadius,
-        bottomRight: _smallRadius,
-      );
-    }
-
-    if (hasMultiplePhotosNoCaption &&
-        (shape == BubbleShape.singleBottom ||
-            shape == BubbleShape.singleMiddle)) {
-      return BorderRadius.only(
-        topLeft: isMe ? _bigRadius : _smallRadius,
-        topRight: _smallRadius,
-        bottomLeft: isMe ? _bigRadius : _smallRadius,
-        bottomRight: isMe ? _smallRadius : _bigRadius,
-      );
-    }
-
-    Radius cornerTL = isMe ? outsideRadius : _bigRadius;
-    Radius cornerTR = isMe ? _bigRadius : outsideRadius;
-    Radius cornerBL = isMe ? outsideRadius : _bigRadius;
-    Radius cornerBR = isMe ? _bigRadius : outsideRadius;
-
-    switch (shape) {
-      case BubbleShape.singleTop:
-        if (isMe) {
-          cornerBR = _smallRadius;
-        } else {
-          cornerBL = _smallRadius;
-        }
-      case BubbleShape.singleBottom:
-        if (isMe) {
-          cornerTR = _smallRadius;
-        } else {
-          cornerTL = _smallRadius;
-        }
-      case BubbleShape.singleMiddle:
-        break;
-      case BubbleShape.groupedMiddle:
-        if (isMe) {
-          cornerTR = _smallRadius;
-          cornerBR = _smallRadius;
-        } else {
-          cornerTL = _smallRadius;
-          cornerBL = _smallRadius;
-        }
-    }
-
-    return BorderRadius.only(
-      topLeft: cornerTL,
-      topRight: cornerTR,
-      bottomLeft: cornerBL,
-      bottomRight: cornerBR,
+    final isTop = shape == BubbleShape.singleTop || shape == BubbleShape.singleMiddle;
+    final isBottom = shape == BubbleShape.singleBottom || shape == BubbleShape.singleMiddle;
+    return computeBubbleRadius(
+      isMe: isMe,
+      isTop: isTop,
+      isBottom: isBottom,
+      style: bubbleStyle,
+      behavior: bubbleBehavior,
+      hasPhotoWithCaption: hasPhotoWithCaption,
+      hasMultiplePhotosNoCaption: hasMultiplePhotosNoCaption,
     );
   }
 
@@ -352,9 +304,11 @@ class MessageBubble extends StatelessWidget {
                   radius: 15,
                   backgroundColor: Color(0x00000000),
                 ),
-              ValueListenableBuilder<BubbleStyle>(
-                valueListenable: AppBubbleShape.current,
-                builder: (context, bubbleStyle, child) {
+              ListenableBuilder(
+                listenable: Listenable.merge(
+                  [AppBubbleShape.current, AppBubbleBehavior.current],
+                ),
+                builder: (context, child) {
                   return Container(
                     constraints: BoxConstraints(
                       maxWidth: MediaQuery.sizeOf(context).width * 0.75,
@@ -364,7 +318,8 @@ class MessageBubble extends StatelessWidget {
                           ? cs.primaryContainer
                           : cs.surfaceContainerHighest,
                       borderRadius: _borderRadiusFor(
-                        bubbleStyle,
+                        AppBubbleShape.current.value,
+                        AppBubbleBehavior.current.value,
                         shape,
                         hasPhotoCap,
                         hasMultiPhotos,
diff --git a/lib/main.dart b/lib/main.dart
index 1f4c250..951c017 100644
--- a/lib/main.dart
+++ b/lib/main.dart
@@ -8,6 +8,7 @@ import 'package:package_info_plus/package_info_plus.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 import 'backend/api.dart';
 import 'core/config/app_accent.dart';
+import 'core/config/app_bubble_behavior.dart';
 import 'core/config/app_bubble_shape.dart';
 import 'core/config/app_cache_extent.dart';
 import 'core/config/app_fonts.dart';
@@ -75,6 +76,7 @@ void main() async {
   );
   final initialAccentSeed = await AppAccent.load();
   AppBubbleShape.current.value = await AppBubbleShape.load();
+  AppBubbleBehavior.current.value = await AppBubbleBehavior.load();
   AppCacheExtent.current.value = await AppCacheExtent.load();
   runApp(
     KometApp(