diff --git a/lib/pages/settings_style/settings_style.dart b/lib/pages/settings_style/settings_style.dart
index aecace3..d8bd001 100644
--- a/lib/pages/settings_style/settings_style.dart
+++ b/lib/pages/settings_style/settings_style.dart
@@ -10,6 +10,7 @@ import 'package:tatchat/utils/file_selector.dart';
 import 'package:tatchat/widgets/future_loading_dialog.dart';
 import 'package:tatchat/widgets/theme_builder.dart';
 import 'package:material_ui/material_ui.dart';
+import 'package:matrix/matrix.dart';
 
 import '../../widgets/matrix.dart';
 import 'settings_style_view.dart';
@@ -22,11 +23,18 @@ class SettingsStyle extends StatefulWidget {
 }
 
 class SettingsStyleController extends State<SettingsStyle> {
-  void setChatColor(Color? color) {
+  Future<void> setChatColor(Color? color) async {
+    final client = Matrix.of(context).client;
+    final themeController = ThemeController.of(context);
     AppSettings.colorSchemeSeedInt.setItem(
       color?.toARGB32() ?? AppSettings.colorSchemeSeedInt.defaultValue,
     );
-    ThemeController.of(context).setPrimaryColor(color);
+    await themeController.setPrimaryColor(color);
+    try {
+      await client.setApplicationAccountColor(color?.toARGB32());
+    } catch (e, s) {
+      Logs().e('Unable to save chat color', e, s);
+    }
   }
 
   Future<void> setWallpaper() async {
@@ -105,12 +113,19 @@ class SettingsStyleController extends State<SettingsStyle> {
     });
   }
 
-  void deleteChatWallpaper() => showFutureLoadingDialog(
-    context: context,
-    future: () => Matrix.of(context).client.setApplicationAccountConfig(
-      const ApplicationAccountConfig(wallpaperUrl: null, wallpaperBlur: null),
-    ),
-  );
+  void deleteChatWallpaper() {
+    final client = Matrix.of(context).client;
+    showFutureLoadingDialog(
+      context: context,
+      future: () => client.setApplicationAccountConfig(
+        ApplicationAccountConfig(
+          wallpaperUrl: null,
+          wallpaperBlur: null,
+          primaryColor: client.applicationAccountConfig.primaryColor,
+        ),
+      ),
+    );
+  }
 
   ThemeMode get currentTheme => ThemeController.of(context).themeMode;
   Color? get currentColor => ThemeController.of(context).primaryColor;
diff --git a/lib/utils/account_config.dart b/lib/utils/account_config.dart
index a5f246a..78e3846 100644
--- a/lib/utils/account_config.dart
+++ b/lib/utils/account_config.dart
@@ -27,20 +27,35 @@ extension ApplicationAccountConfigExtension on Client {
         wallpaperOpacity:
             config.wallpaperOpacity ?? currentConfig.wallpaperOpacity,
         wallpaperBlur: config.wallpaperBlur ?? currentConfig.wallpaperBlur,
+        primaryColor: config.primaryColor ?? currentConfig.primaryColor,
       ).toJson(),
     );
   }
+
+  Future<void> setApplicationAccountColor(int? primaryColor) {
+    final currentConfig = applicationAccountConfig;
+    return setApplicationAccountConfig(
+      ApplicationAccountConfig(
+        wallpaperUrl: currentConfig.wallpaperUrl,
+        wallpaperOpacity: currentConfig.wallpaperOpacity,
+        wallpaperBlur: currentConfig.wallpaperBlur,
+        primaryColor: primaryColor,
+      ),
+    );
+  }
 }
 
 class ApplicationAccountConfig {
   final Uri? wallpaperUrl;
   final double? wallpaperOpacity;
   final double? wallpaperBlur;
+  final int? primaryColor;
 
   const ApplicationAccountConfig({
     this.wallpaperUrl,
     this.wallpaperOpacity,
     this.wallpaperBlur,
+    this.primaryColor,
   });
 
   static double _sanitizedOpacity(double? opacity) {
@@ -58,11 +73,13 @@ class ApplicationAccountConfig {
           json.tryGet<double>('wallpaper_opacity'),
         ),
         wallpaperBlur: json.tryGet<double>('wallpaper_blur'),
+        primaryColor: json.tryGet<int>('primary_color'),
       );
 
   Map<String, dynamic> toJson() => {
     'wallpaper_url': wallpaperUrl?.toString(),
     'wallpaper_opacity': wallpaperOpacity,
     'wallpaper_blur': wallpaperBlur,
+    'primary_color': primaryColor,
   };
 }
diff --git a/lib/widgets/matrix.dart b/lib/widgets/matrix.dart
index 31e7082..fdaa47c 100644
--- a/lib/widgets/matrix.dart
+++ b/lib/widgets/matrix.dart
@@ -44,10 +44,13 @@ class Matrix extends StatefulWidget {
 
   final SharedPreferences store;
 
+  final ValueChanged<Client?>? onActiveClientChanged;
+
   const Matrix({
     this.child,
     required this.clients,
     required this.store,
+    this.onActiveClientChanged,
     this.queryParameters,
     super.key,
   });
@@ -89,11 +92,21 @@ class MatrixState extends State<Matrix> {
     final i = widget.clients.indexWhere((c) => c == cl);
     if (i != -1) {
       _activeClient = i;
+      _notifyActiveClientChanged();
     } else {
       Logs().w('Tried to set an unknown client ${cl!.userID} as active');
     }
   }
 
+  void _notifyActiveClientChanged() {
+    final callback = widget.onActiveClientChanged;
+    if (callback == null) return;
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      if (!mounted) return;
+      callback(widget.clients.isEmpty ? null : client);
+    });
+  }
+
   List<Client?>? get currentBundle {
     if (!hasComplexBundles) {
       return List.from(widget.clients);
@@ -256,19 +269,27 @@ class MatrixState extends State<Matrix> {
         .where((state) => state == LoginState.loggedOut)
         .listen((_) {
           final loggedInWithMultipleClients = widget.clients.length > 1;
+          final activeClient = client;
+          final removedIndex = widget.clients.indexOf(c);
+          final wasActive = removedIndex != -1 && activeClient == c;
 
           _cancelSubs(c.clientName);
           widget.clients.remove(c);
           ClientManager.removeClientNameFromStore(c.clientName, store);
           InitWithRestoreExtension.deleteSessionBackup(name);
+          if (removedIndex != -1 && _activeClient > removedIndex) {
+            _activeClient--;
+          }
+          if (wasActive) {
+            _activeClient = -1;
+          }
+          if (removedIndex != -1) {
+            _notifyActiveClientChanged();
+          }
 
           if (loggedInWithMultipleClients) {
             final snackbarContext =
-                TatuChatApp
-                    .router
-                    .routerDelegate
-                    .navigatorKey
-                    .currentContext ??
+                TatuChatApp.router.routerDelegate.navigatorKey.currentContext ??
                 context;
 
             if (!snackbarContext.mounted) return;
@@ -349,6 +370,7 @@ class MatrixState extends State<Matrix> {
         },
       );
     }
+    _notifyActiveClientChanged();
   }
 
   void didChangeAppLifecycleState(AppLifecycleState state) {
diff --git a/lib/widgets/tatu_chat_app.dart b/lib/widgets/tatu_chat_app.dart
index 850fdcc..3d7384f 100644
--- a/lib/widgets/tatu_chat_app.dart
+++ b/lib/widgets/tatu_chat_app.dart
@@ -65,38 +65,46 @@ class TatuChatApp extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     return ThemeBuilder(
-      builder: (context, themeMode, primaryColor) => MaterialApp.router(
-        title: AppSettings.applicationName.value,
-        themeMode: themeMode,
-        theme: FluffyThemes.buildTheme(context, Brightness.light, primaryColor),
-        darkTheme: FluffyThemes.buildTheme(
-          context,
-          Brightness.dark,
-          primaryColor,
-        ),
-        scrollBehavior: CustomScrollBehavior(),
-        localizationsDelegates: [
-          ...L10n.localizationsDelegates,
-          ...GlobalMaterialLocalizations.delegates,
-          ...GlobalCupertinoLocalizations.delegates,
-        ],
-        supportedLocales: L10n.supportedLocales,
-        routerConfig: router,
-        builder: (context, child) => AppLockWidget(
-          pincode: appLockSettings.pincode,
-          useBiometrics: appLockSettings.useBiometrics,
-          isLoggedIn: clients.any((client) => client.isLogged()),
-          // Need a navigator above the Matrix widget for
-          // displaying dialogs
-          child: Matrix(
-            clients: clients,
-            store: store,
-            child: CallOverlay(
-              child: testWidget ?? child ?? const SizedBox.shrink(),
+      builder: (context, themeMode, primaryColor, themeController) =>
+          MaterialApp.router(
+            title: AppSettings.applicationName.value,
+            themeMode: themeMode,
+            theme: FluffyThemes.buildTheme(
+              context,
+              Brightness.light,
+              primaryColor,
+            ),
+            darkTheme: FluffyThemes.buildTheme(
+              context,
+              Brightness.dark,
+              primaryColor,
+            ),
+            scrollBehavior: CustomScrollBehavior(),
+            localizationsDelegates: [
+              ...L10n.localizationsDelegates,
+              ...GlobalMaterialLocalizations.delegates,
+              ...GlobalCupertinoLocalizations.delegates,
+            ],
+            supportedLocales: L10n.supportedLocales,
+            routerConfig: router,
+            builder: (context, child) => AppLockWidget(
+              pincode: appLockSettings.pincode,
+              useBiometrics: appLockSettings.useBiometrics,
+              isLoggedIn: clients.any((client) => client.isLogged()),
+              // Need a navigator above the Matrix widget for
+              // displaying dialogs
+              child: Matrix(
+                clients: clients,
+                store: store,
+                onActiveClientChanged: (client) {
+                  themeController.setAccountClient(client);
+                },
+                child: CallOverlay(
+                  child: testWidget ?? child ?? const SizedBox.shrink(),
+                ),
+              ),
             ),
           ),
-        ),
-      ),
     );
   }
 }
diff --git a/lib/widgets/theme_builder.dart b/lib/widgets/theme_builder.dart
index ecb8446..3ab0b3d 100644
--- a/lib/widgets/theme_builder.dart
+++ b/lib/widgets/theme_builder.dart
@@ -3,10 +3,14 @@
 //
 // SPDX-License-Identifier: AGPL-3.0-or-later
 
+import 'dart:async';
+
 import 'package:collection/collection.dart';
 import 'package:dynamic_color/dynamic_color.dart';
+import 'package:tatchat/utils/account_config.dart';
 import 'package:tatchat/utils/color_value.dart';
 import 'package:material_ui/material_ui.dart';
+import 'package:matrix/matrix.dart';
 import 'package:provider/provider.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 
@@ -15,6 +19,7 @@ class ThemeBuilder extends StatefulWidget {
     BuildContext context,
     ThemeMode themeMode,
     Color? primaryColor,
+    ThemeController controller,
   )
   builder;
 
@@ -36,6 +41,11 @@ class ThemeController extends State<ThemeBuilder> {
   SharedPreferences? _sharedPreferences;
   ThemeMode? _themeMode;
   Color? _primaryColor;
+  Color? _localPrimaryColor;
+  Color? _accountPrimaryColor;
+  Client? _accountClient;
+  StreamSubscription<SyncUpdate>? _accountClientSubscription;
+  int _accountClientGeneration = 0;
 
   ThemeMode get themeMode => _themeMode ?? ThemeMode.system;
 
@@ -44,6 +54,15 @@ class ThemeController extends State<ThemeBuilder> {
   static ThemeController of(BuildContext context) =>
       Provider.of<ThemeController>(context, listen: false);
 
+  void _updatePrimaryColor() {
+    if (!mounted) return;
+    final newColor = _accountPrimaryColor ?? _localPrimaryColor;
+    if (newColor == _primaryColor) return;
+    setState(() {
+      _primaryColor = newColor;
+    });
+  }
+
   Future<void> _loadData(_) async {
     final preferences = _sharedPreferences ??=
         await SharedPreferences.getInstance();
@@ -51,12 +70,14 @@ class ThemeController extends State<ThemeBuilder> {
     final rawThemeMode = preferences.getString(widget.themeModeSettingsKey);
     final rawColor = preferences.getInt(widget.primaryColorSettingsKey);
 
+    if (!mounted) return;
     setState(() {
       _themeMode = ThemeMode.values.singleWhereOrNull(
         (value) => value.name == rawThemeMode,
       );
-      _primaryColor = rawColor == null ? null : Color(rawColor);
+      _localPrimaryColor = rawColor == null ? null : Color(rawColor);
     });
+    _updatePrimaryColor();
   }
 
   Future<void> setThemeMode(ThemeMode newThemeMode) async {
@@ -69,6 +90,12 @@ class ThemeController extends State<ThemeBuilder> {
   }
 
   Future<void> setPrimaryColor(Color? newPrimaryColor) async {
+    if (!mounted) return;
+    setState(() {
+      _localPrimaryColor = newPrimaryColor;
+      _accountPrimaryColor = newPrimaryColor;
+      _primaryColor = newPrimaryColor;
+    });
     final preferences = _sharedPreferences ??=
         await SharedPreferences.getInstance();
     if (newPrimaryColor == null) {
@@ -79,9 +106,56 @@ class ThemeController extends State<ThemeBuilder> {
         newPrimaryColor.hexValue,
       );
     }
-    setState(() {
-      _primaryColor = newPrimaryColor;
-    });
+  }
+
+  void setAccountClient(Client? client) {
+    if (!mounted) return;
+    final generation = ++_accountClientGeneration;
+    _accountClientSubscription?.cancel();
+    _accountClientSubscription = null;
+    _accountClient = client;
+    _accountPrimaryColor = null;
+    _updatePrimaryColor();
+    if (client == null) return;
+
+    unawaited(_loadAccountClientColor(client, generation));
+    _accountClientSubscription = client.onSync.stream
+        .where(
+          (sync) =>
+              sync.accountData?.any(
+                (accountData) =>
+                    accountData.type ==
+                    ApplicationAccountConfigExtension.accountDataKey,
+              ) ??
+              false,
+        )
+        .listen((_) => _applyAccountClientColor(client, generation));
+  }
+
+  Future<void> _loadAccountClientColor(Client client, int generation) async {
+    final accountDataLoading = client.accountDataLoading;
+    if (accountDataLoading != null) {
+      try {
+        await accountDataLoading;
+      } catch (_) {}
+    }
+    if (!mounted ||
+        generation != _accountClientGeneration ||
+        !identical(_accountClient, client)) {
+      return;
+    }
+    _applyAccountClientColor(client, generation);
+  }
+
+  void _applyAccountClientColor(Client client, int generation) {
+    if (!mounted ||
+        generation != _accountClientGeneration ||
+        !identical(_accountClient, client)) {
+      return;
+    }
+    final primaryColor = client.applicationAccountConfig.primaryColor;
+    _accountPrimaryColor = primaryColor == null ? null : Color(primaryColor);
+    _updatePrimaryColor();
   }
 
   @override
@@ -95,9 +169,19 @@ class ThemeController extends State<ThemeBuilder> {
     return Provider(
       create: (_) => this,
       child: DynamicColorBuilder(
-        builder: (light, _) =>
-            widget.builder(context, themeMode, primaryColor ?? light?.primary),
+        builder: (light, _) => widget.builder(
+          context,
+          themeMode,
+          primaryColor ?? light?.primary,
+          this,
+        ),
       ),
     );
   }
+
+  @override
+  void dispose() {
+    _accountClientSubscription?.cancel();
+    super.dispose();
+  }
 }
diff --git a/test/account_config_test.dart b/test/account_config_test.dart
new file mode 100644
index 0000000..4acae20
--- /dev/null
+++ b/test/account_config_test.dart
@@ -0,0 +1,67 @@
+// SPDX-FileCopyrightText: 2026 TatuChat
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:tatchat/utils/account_config.dart';
+
+void main() {
+  group('ApplicationAccountConfig', () {
+    test('Parses primary color from account data', () {
+      final config = ApplicationAccountConfig.fromJson({
+        'primary_color': 0xFF6750A4,
+      });
+      expect(config.primaryColor, 0xFF6750A4);
+    });
+
+    test('Ignores primary color of unexpected type', () {
+      expect(
+        ApplicationAccountConfig.fromJson({
+          'primary_color': '4286369748',
+        }).primaryColor,
+        isNull,
+      );
+      expect(
+        ApplicationAccountConfig.fromJson({'primary_color': 1.5}).primaryColor,
+        isNull,
+      );
+    });
+
+    test('Defaults primary color to null when absent', () {
+      expect(ApplicationAccountConfig.fromJson({}).primaryColor, isNull);
+    });
+
+    test('Serializes primary color', () {
+      const config = ApplicationAccountConfig(primaryColor: 0xFF00D084);
+      expect(config.toJson()['primary_color'], 0xFF00D084);
+    });
+
+    test('Serializes missing primary color as null', () {
+      const config = ApplicationAccountConfig(wallpaperOpacity: 0.5);
+      expect(config.toJson()['primary_color'], isNull);
+    });
+
+    test('Round trips through json', () {
+      final config = ApplicationAccountConfig(
+        wallpaperUrl: Uri.parse('mxc://example.invalid/wallpaper'),
+        wallpaperOpacity: 0.3,
+        wallpaperBlur: 4,
+        primaryColor: 0xFF6750A4,
+      );
+      final parsed = ApplicationAccountConfig.fromJson(config.toJson());
+      expect(parsed.wallpaperUrl, config.wallpaperUrl);
+      expect(parsed.wallpaperOpacity, config.wallpaperOpacity);
+      expect(parsed.wallpaperBlur, config.wallpaperBlur);
+      expect(parsed.primaryColor, config.primaryColor);
+    });
+
+    test('Keeps existing wallpaper defaults when parsing color only', () {
+      final config = ApplicationAccountConfig.fromJson({
+        'primary_color': 0xFF6750A4,
+      });
+      expect(config.wallpaperUrl, isNull);
+      expect(config.wallpaperOpacity, 1);
+      expect(config.wallpaperBlur, isNull);
+    });
+  });
+}