feat(backup): include installed extensions and settings in backup/restore

Back up the store registry URL plus each installed extension (id, version, enabled flag and settings) and restore them on a new device by reinstalling from the store and re-applying settings. Secret-flagged settings (tokens/API keys) are excluded by default behind an opt-in 'Include extension credentials' toggle. Device-bound signed sessions are never backed up. Settings are merged on restore so omitted secrets are not wiped; failed reinstalls are reported.

lib/l10n/app_localizations.dart

@@ -5161,6 +5161,30 @@ abstract class AppLocalizations {
   /// **'{count, plural, =1{1 favorite artist} other{{count} favorite artists}}'**
   String backupContentsArtists(int count);
 
+  /// Backup contents row for installed extensions count
+  ///
+  /// In en, this message translates to:
+  /// **'{count, plural, =1{1 extension} other{{count} extensions}}'**
+  String backupContentsExtensions(int count);
+
+  /// Toggle to include secret extension settings (tokens, API keys) in the backup
+  ///
+  /// In en, this message translates to:
+  /// **'Include extension credentials'**
+  String get backupIncludeSecrets;
+
+  /// Explanation for the include-credentials toggle
+  ///
+  /// In en, this message translates to:
+  /// **'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.'**
+  String get backupIncludeSecretsDescription;
+
+  /// Snackbar/hint when some extensions failed to reinstall during restore
+  ///
+  /// In en, this message translates to:
+  /// **'{count} {count, plural, =1{extension} other{extensions}} could not be reinstalled. Install them manually from the store.'**
+  String backupExtensionsRestoreFailed(int count);
+
   /// Tooltip for the Love All button on album/playlist screens
   ///
   /// In en, this message translates to:
@@ -5373,6 +5397,24 @@ abstract class AppLocalizations {
   /// **'Using standard network settings'**
   String get downloadNetworkCompatibilityModeDisabled;
 
+  /// Setting title for allowing requests to private/local network targets
+  ///
+  /// In en, this message translates to:
+  /// **'Allow Local Network Access'**
+  String get downloadAllowLocalNetwork;
+
+  /// Subtitle when allow local network access is on
+  ///
+  /// In en, this message translates to:
+  /// **'Requests to local/private addresses are allowed (for local proxy or custom DNS)'**
+  String get downloadAllowLocalNetworkEnabled;
+
+  /// Subtitle when allow local network access is off
+  ///
+  /// In en, this message translates to:
+  /// **'Local/private addresses are blocked for security'**
+  String get downloadAllowLocalNetworkDisabled;
+
   /// Subtitle when quality picker is disabled due to extension service
   ///
   /// In en, this message translates to:

lib/l10n/app_localizations_ar.dart

@@ -3014,6 +3014,35 @@ class AppLocalizationsAr extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extensions',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Include extension credentials';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: 'extensions',
+      one: 'extension',
+    );
+    return '$count $_temp0 could not be reinstalled. Install them manually from the store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Love All';
 
@@ -3143,6 +3172,17 @@ class AppLocalizationsAr extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Using standard network settings';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Allow Local Network Access';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Requests to local/private addresses are allowed (for local proxy or custom DNS)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Local/private addresses are blocked for security';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/app_localizations_de.dart

@@ -3051,6 +3051,35 @@ class AppLocalizationsDe extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extensions',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Include extension credentials';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: 'extensions',
+      one: 'extension',
+    );
+    return '$count $_temp0 could not be reinstalled. Install them manually from the store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Alle lieben';
 
@@ -3183,6 +3212,17 @@ class AppLocalizationsDe extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Standard-Netzwerkeinstellungen verwenden';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Allow Local Network Access';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Requests to local/private addresses are allowed (for local proxy or custom DNS)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Local/private addresses are blocked for security';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/app_localizations_en.dart

@@ -3014,6 +3014,35 @@ class AppLocalizationsEn extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extensions',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Include extension credentials';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: 'extensions',
+      one: 'extension',
+    );
+    return '$count $_temp0 could not be reinstalled. Install them manually from the store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Love All';
 
@@ -3143,6 +3172,17 @@ class AppLocalizationsEn extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Using standard network settings';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Allow Local Network Access';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Requests to local/private addresses are allowed (for local proxy or custom DNS)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Local/private addresses are blocked for security';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/app_localizations_es.dart

@@ -3014,6 +3014,35 @@ class AppLocalizationsEs extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extensions',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Include extension credentials';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: 'extensions',
+      one: 'extension',
+    );
+    return '$count $_temp0 could not be reinstalled. Install them manually from the store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Love All';
 
@@ -3143,6 +3172,17 @@ class AppLocalizationsEs extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Using standard network settings';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Allow Local Network Access';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Requests to local/private addresses are allowed (for local proxy or custom DNS)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Local/private addresses are blocked for security';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/app_localizations_fr.dart

@@ -3091,6 +3091,35 @@ class AppLocalizationsFr extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extensions',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Include extension credentials';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: 'extensions',
+      one: 'extension',
+    );
+    return '$count $_temp0 could not be reinstalled. Install them manually from the store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Tout aimer';
 
@@ -3228,6 +3257,17 @@ class AppLocalizationsFr extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Utilisation des paramètres réseau par défaut';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Allow Local Network Access';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Requests to local/private addresses are allowed (for local proxy or custom DNS)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Local/private addresses are blocked for security';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/app_localizations_hi.dart

@@ -3014,6 +3014,35 @@ class AppLocalizationsHi extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extensions',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Include extension credentials';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: 'extensions',
+      one: 'extension',
+    );
+    return '$count $_temp0 could not be reinstalled. Install them manually from the store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Love All';
 
@@ -3143,6 +3172,17 @@ class AppLocalizationsHi extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Using standard network settings';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Allow Local Network Access';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Requests to local/private addresses are allowed (for local proxy or custom DNS)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Local/private addresses are blocked for security';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/app_localizations_id.dart

@@ -3004,6 +3004,29 @@ class AppLocalizationsId extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extension',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Sertakan kredensial extension';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Token dan API key dari extension akan ikut disimpan ke file cadangan. Jaga kerahasiaan file-nya. Jika dimatikan, kamu perlu memasukkannya lagi setelah pemulihan.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    return '$count extension gagal dipasang ulang. Pasang manual dari store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Love All';
 
@@ -3133,6 +3156,17 @@ class AppLocalizationsId extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Using standard network settings';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Izinkan Akses Jaringan Lokal';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Permintaan ke alamat lokal/privat diizinkan (untuk proxy lokal atau DNS kustom)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Alamat lokal/privat diblokir demi keamanan';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/app_localizations_ja.dart

@@ -3002,6 +3002,35 @@ class AppLocalizationsJa extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extensions',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Include extension credentials';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: 'extensions',
+      one: 'extension',
+    );
+    return '$count $_temp0 could not be reinstalled. Install them manually from the store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Love All';
 
@@ -3131,6 +3160,17 @@ class AppLocalizationsJa extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Using standard network settings';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Allow Local Network Access';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Requests to local/private addresses are allowed (for local proxy or custom DNS)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Local/private addresses are blocked for security';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/app_localizations_ko.dart

@@ -2999,6 +2999,35 @@ class AppLocalizationsKo extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extensions',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Include extension credentials';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: 'extensions',
+      one: 'extension',
+    );
+    return '$count $_temp0 could not be reinstalled. Install them manually from the store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Love All';
 
@@ -3128,6 +3157,17 @@ class AppLocalizationsKo extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Using standard network settings';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Allow Local Network Access';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Requests to local/private addresses are allowed (for local proxy or custom DNS)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Local/private addresses are blocked for security';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/app_localizations_nl.dart

@@ -3014,6 +3014,35 @@ class AppLocalizationsNl extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extensions',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Include extension credentials';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: 'extensions',
+      one: 'extension',
+    );
+    return '$count $_temp0 could not be reinstalled. Install them manually from the store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Love All';
 
@@ -3143,6 +3172,17 @@ class AppLocalizationsNl extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Using standard network settings';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Allow Local Network Access';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Requests to local/private addresses are allowed (for local proxy or custom DNS)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Local/private addresses are blocked for security';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/app_localizations_pt.dart

@@ -3014,6 +3014,35 @@ class AppLocalizationsPt extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extensions',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Include extension credentials';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: 'extensions',
+      one: 'extension',
+    );
+    return '$count $_temp0 could not be reinstalled. Install them manually from the store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Love All';
 
@@ -3143,6 +3172,17 @@ class AppLocalizationsPt extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Using standard network settings';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Allow Local Network Access';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Requests to local/private addresses are allowed (for local proxy or custom DNS)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Local/private addresses are blocked for security';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/app_localizations_ru.dart

@@ -3069,6 +3069,35 @@ class AppLocalizationsRu extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extensions',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Include extension credentials';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: 'extensions',
+      one: 'extension',
+    );
+    return '$count $_temp0 could not be reinstalled. Install them manually from the store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Love All';
 
@@ -3198,6 +3227,17 @@ class AppLocalizationsRu extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Using standard network settings';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Allow Local Network Access';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Requests to local/private addresses are allowed (for local proxy or custom DNS)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Local/private addresses are blocked for security';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/app_localizations_tr.dart

@@ -3043,6 +3043,35 @@ class AppLocalizationsTr extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extensions',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Include extension credentials';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: 'extensions',
+      one: 'extension',
+    );
+    return '$count $_temp0 could not be reinstalled. Install them manually from the store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Love All';
 
@@ -3175,6 +3204,17 @@ class AppLocalizationsTr extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Using standard network settings';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Allow Local Network Access';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Requests to local/private addresses are allowed (for local proxy or custom DNS)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Local/private addresses are blocked for security';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/app_localizations_uk.dart

@@ -3058,6 +3058,35 @@ class AppLocalizationsUk extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extensions',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Include extension credentials';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: 'extensions',
+      one: 'extension',
+    );
+    return '$count $_temp0 could not be reinstalled. Install them manually from the store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Уподобати всіх';
 
@@ -3190,6 +3219,17 @@ class AppLocalizationsUk extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Using standard network settings';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Allow Local Network Access';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Requests to local/private addresses are allowed (for local proxy or custom DNS)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Local/private addresses are blocked for security';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/app_localizations_zh.dart

@@ -3014,6 +3014,35 @@ class AppLocalizationsZh extends AppLocalizations {
     return '$_temp0';
   }
 
+  @override
+  String backupContentsExtensions(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count extensions',
+      one: '1 extension',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get backupIncludeSecrets => 'Include extension credentials';
+
+  @override
+  String get backupIncludeSecretsDescription =>
+      'Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.';
+
+  @override
+  String backupExtensionsRestoreFailed(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: 'extensions',
+      one: 'extension',
+    );
+    return '$count $_temp0 could not be reinstalled. Install them manually from the store.';
+  }
+
   @override
   String get tooltipLoveAll => 'Love All';
 
@@ -3143,6 +3172,17 @@ class AppLocalizationsZh extends AppLocalizations {
   String get downloadNetworkCompatibilityModeDisabled =>
       'Using standard network settings';
 
+  @override
+  String get downloadAllowLocalNetwork => 'Allow Local Network Access';
+
+  @override
+  String get downloadAllowLocalNetworkEnabled =>
+      'Requests to local/private addresses are allowed (for local proxy or custom DNS)';
+
+  @override
+  String get downloadAllowLocalNetworkDisabled =>
+      'Local/private addresses are blocked for security';
+
   @override
   String get downloadSelectServiceToEnable =>
       'Select a provider with quality options to enable this option';

lib/l10n/arb/app_en.arb

@@ -3964,6 +3964,32 @@
       }
     }
   },
+  "backupContentsExtensions": "{count, plural, =1{1 extension} other{{count} extensions}}",
+  "@backupContentsExtensions": {
+    "description": "Backup contents row for installed extensions count",
+    "placeholders": {
+      "count": {
+        "type": "int"
+      }
+    }
+  },
+  "backupIncludeSecrets": "Include extension credentials",
+  "@backupIncludeSecrets": {
+    "description": "Toggle to include secret extension settings (tokens, API keys) in the backup"
+  },
+  "backupIncludeSecretsDescription": "Tokens and API keys from extensions will be saved into the backup file. Keep the file private. When off, you re-enter them after restoring.",
+  "@backupIncludeSecretsDescription": {
+    "description": "Explanation for the include-credentials toggle"
+  },
+  "backupExtensionsRestoreFailed": "{count} {count, plural, =1{extension} other{extensions}} could not be reinstalled. Install them manually from the store.",
+  "@backupExtensionsRestoreFailed": {
+    "description": "Snackbar/hint when some extensions failed to reinstall during restore",
+    "placeholders": {
+      "count": {
+        "type": "int"
+      }
+    }
+  },
   "tooltipLoveAll": "Love All",
   "@tooltipLoveAll": {
     "description": "Tooltip for the Love All button on album/playlist screens"
@@ -4120,6 +4146,18 @@
   "@downloadNetworkCompatibilityModeDisabled": {
     "description": "Subtitle when network compatibility mode is off"
   },
+  "downloadAllowLocalNetwork": "Allow Local Network Access",
+  "@downloadAllowLocalNetwork": {
+    "description": "Setting title for allowing requests to private/local network targets"
+  },
+  "downloadAllowLocalNetworkEnabled": "Requests to local/private addresses are allowed (for local proxy or custom DNS)",
+  "@downloadAllowLocalNetworkEnabled": {
+    "description": "Subtitle when allow local network access is on"
+  },
+  "downloadAllowLocalNetworkDisabled": "Local/private addresses are blocked for security",
+  "@downloadAllowLocalNetworkDisabled": {
+    "description": "Subtitle when allow local network access is off"
+  },
   "downloadSelectServiceToEnable": "Select a provider with quality options to enable this option",
   "@downloadSelectServiceToEnable": {
     "description": "Subtitle when quality picker is disabled due to extension service"

lib/l10n/arb/app_id.arb

@@ -3752,6 +3752,24 @@
       }
     }
   },
+  "backupContentsExtensions": "{count, plural, =1{1 extension} other{{count} extension}}",
+  "@backupContentsExtensions": {
+    "placeholders": {
+      "count": {
+        "type": "int"
+      }
+    }
+  },
+  "backupIncludeSecrets": "Sertakan kredensial extension",
+  "backupIncludeSecretsDescription": "Token dan API key dari extension akan ikut disimpan ke file cadangan. Jaga kerahasiaan file-nya. Jika dimatikan, kamu perlu memasukkannya lagi setelah pemulihan.",
+  "backupExtensionsRestoreFailed": "{count} extension gagal dipasang ulang. Pasang manual dari store.",
+  "@backupExtensionsRestoreFailed": {
+    "placeholders": {
+      "count": {
+        "type": "int"
+      }
+    }
+  },
   "tooltipLoveAll": "Love All",
   "@tooltipLoveAll": {
     "description": "Tooltip for the Love All button on album/playlist screens"
@@ -3892,6 +3910,18 @@
   "@downloadNetworkCompatibilityModeDisabled": {
     "description": "Subtitle when network compatibility mode is disabled"
   },
+  "downloadAllowLocalNetwork": "Izinkan Akses Jaringan Lokal",
+  "@downloadAllowLocalNetwork": {
+    "description": "Setting title for allowing requests to private/local network targets"
+  },
+  "downloadAllowLocalNetworkEnabled": "Permintaan ke alamat lokal/privat diizinkan (untuk proxy lokal atau DNS kustom)",
+  "@downloadAllowLocalNetworkEnabled": {
+    "description": "Subtitle when allow local network access is on"
+  },
+  "downloadAllowLocalNetworkDisabled": "Alamat lokal/privat diblokir demi keamanan",
+  "@downloadAllowLocalNetworkDisabled": {
+    "description": "Subtitle when allow local network access is off"
+  },
   "downloadSelectServiceToEnable": "Select a provider with quality options to enable this option",
   "@downloadSelectServiceToEnable": {
     "description": "Hint shown instead of Ask-quality subtitle when selected provider has no quality options"

lib/providers/extension_provider.dart

@@ -14,6 +14,22 @@ final _log = AppLogger('ExtensionProvider');
 const _metadataProviderPriorityKey = 'metadata_provider_priority';
 const _providerPriorityKey = 'provider_priority';
 const _spotifyWebExtensionId = 'spotify-web';
+const _storeRegistryUrlPrefKey = 'store_registry_url';
+
+/// Result of restoring extensions from a backup.
+class ExtensionRestoreResult {
+  final int installed;
+  final int alreadyPresent;
+  final int failed;
+  final List<String> failedIds;
+
+  const ExtensionRestoreResult({
+    this.installed = 0,
+    this.alreadyPresent = 0,
+    this.failed = 0,
+    this.failedIds = const [],
+  });
+}
 
 bool _stringListEquals(List<String> a, List<String> b) {
   if (identical(a, b)) return true;
@@ -1722,6 +1738,205 @@ class ExtensionNotifier extends Notifier<ExtensionState> {
         .where((ext) => ext.enabled && ext.hasCustomSearch)
         .toList();
   }
+
+  /// Collects the keys flagged as `secret` in an extension's manifest schema
+  /// (top-level settings and quality-specific settings).
+  Set<String> _secretKeysFromManifest(Map<String, dynamic> raw) {
+    final keys = <String>{};
+
+    void scan(Object? settingsList) {
+      if (settingsList is! List) return;
+      for (final entry in settingsList) {
+        if (entry is Map &&
+            entry['secret'] == true &&
+            entry['key'] is String) {
+          keys.add(entry['key'] as String);
+        }
+      }
+    }
+
+    scan(raw['settings']);
+    final quality = raw['quality_options'];
+    if (quality is List) {
+      for (final option in quality) {
+        if (option is Map) {
+          scan(option['settings']);
+        }
+      }
+    }
+    return keys;
+  }
+
+  /// Builds the extensions section of a backup: the store registry URL plus the
+  /// installed extensions with their id, version, enabled flag and settings.
+  /// Secret-flagged settings (tokens, API keys) are only included when
+  /// [includeSecrets] is true.
+  Future<Map<String, dynamic>> exportBackup({
+    required bool includeSecrets,
+  }) async {
+    if (!PlatformBridge.supportsExtensionSystem) {
+      return {'registry_url': '', 'items': const <Map<String, dynamic>>[]};
+    }
+
+    String registryUrl = '';
+    try {
+      registryUrl = await PlatformBridge.getStoreRegistryUrl();
+    } catch (_) {}
+
+    List<Map<String, dynamic>> installed;
+    try {
+      installed = await PlatformBridge.getInstalledExtensions();
+    } catch (e) {
+      _log.w('Backup: failed to list extensions: $e');
+      installed = const [];
+    }
+
+    final items = <Map<String, dynamic>>[];
+    for (final raw in installed) {
+      final id = raw['id'] as String?;
+      if (id == null || id.isEmpty) continue;
+      final secretKeys = _secretKeysFromManifest(raw);
+
+      Map<String, dynamic> settings = {};
+      try {
+        settings = await PlatformBridge.getExtensionSettings(id);
+      } catch (_) {}
+
+      final filtered = <String, dynamic>{};
+      var omittedSecret = false;
+      settings.forEach((key, value) {
+        if (secretKeys.contains(key)) {
+          if (!includeSecrets) {
+            omittedSecret = true;
+            return;
+          }
+        }
+        filtered[key] = value;
+      });
+
+      items.add({
+        'id': id,
+        'version': raw['version']?.toString() ?? '',
+        'enabled': raw['enabled'] == true,
+        'settings': filtered,
+        if (omittedSecret) 'secrets_omitted': true,
+      });
+    }
+
+    return {'registry_url': registryUrl, 'items': items};
+  }
+
+  /// Restores extensions from a backup section produced by [exportBackup]:
+  /// re-applies the store registry URL, reinstalls each extension from the
+  /// store when missing, then merges settings and restores the enabled flag.
+  /// Missing settings (e.g. omitted secrets) are merged with the current values
+  /// so they are not wiped.
+  Future<ExtensionRestoreResult> restoreFromBackup(
+    Map<String, dynamic> data,
+  ) async {
+    if (!PlatformBridge.supportsExtensionSystem) {
+      return const ExtensionRestoreResult();
+    }
+
+    final registryUrl = (data['registry_url'] as String?)?.trim() ?? '';
+    final itemsRaw = data['items'];
+    final items = itemsRaw is List
+        ? itemsRaw
+              .whereType<Map<Object?, Object?>>()
+              .map((e) => Map<String, dynamic>.from(e))
+              .toList()
+        : <Map<String, dynamic>>[];
+
+    Directory? destDir;
+    try {
+      final tmp = await getTemporaryDirectory();
+      destDir = await Directory(
+        '${tmp.path}/spotiflac_restore_ext',
+      ).create(recursive: true);
+      await PlatformBridge.initExtensionStore(destDir.path);
+      if (registryUrl.isNotEmpty) {
+        await PlatformBridge.setStoreRegistryUrl(registryUrl);
+        final prefs = await SharedPreferences.getInstance();
+        await prefs.setString(_storeRegistryUrlPrefKey, registryUrl);
+      }
+    } catch (e) {
+      _log.w('Restore: failed to prepare extension store: $e');
+    }
+
+    await refreshExtensions();
+    final installedIds = state.extensions
+        .map((e) => e.id.toLowerCase())
+        .toSet();
+
+    var installedCount = 0;
+    var alreadyPresent = 0;
+    var failed = 0;
+    final failedIds = <String>[];
+
+    for (final item in items) {
+      final id = item['id'] as String?;
+      if (id == null || id.isEmpty) continue;
+      final enabled = item['enabled'] != false;
+      var present = installedIds.contains(id.toLowerCase());
+
+      if (!present) {
+        if (destDir == null) {
+          failed++;
+          failedIds.add(id);
+          continue;
+        }
+        try {
+          final path = await PlatformBridge.downloadStoreExtension(
+            id,
+            destDir.path,
+          );
+          final ok = await installExtension(path);
+          if (ok) {
+            installedCount++;
+            present = true;
+          } else {
+            failed++;
+            failedIds.add(id);
+          }
+        } catch (e) {
+          _log.w('Restore: failed to install extension $id: $e');
+          failed++;
+          failedIds.add(id);
+        }
+      } else {
+        alreadyPresent++;
+      }
+
+      if (!present) continue;
+
+      final settings = item['settings'];
+      if (settings is Map && settings.isNotEmpty) {
+        try {
+          final current = await PlatformBridge.getExtensionSettings(id);
+          final merged = <String, dynamic>{
+            ...current,
+            ...Map<String, dynamic>.from(settings),
+          };
+          await PlatformBridge.setExtensionSettings(id, merged);
+        } catch (e) {
+          _log.w('Restore: failed to apply settings for $id: $e');
+        }
+      }
+
+      try {
+        await setExtensionEnabled(id, enabled);
+      } catch (_) {}
+    }
+
+    await refreshExtensions();
+
+    return ExtensionRestoreResult(
+      installed: installedCount,
+      alreadyPresent: alreadyPresent,
+      failed: failed,
+      failedIds: failedIds,
+    );
+  }
 }
 
 final extensionProvider = NotifierProvider<ExtensionNotifier, ExtensionState>(

lib/screens/settings/backup_restore_page.dart

@@ -6,6 +6,7 @@ import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:share_plus/share_plus.dart' show ShareParams, SharePlus, XFile;
 import 'package:spotiflac_android/l10n/l10n.dart';
 import 'package:spotiflac_android/providers/download_queue_provider.dart';
+import 'package:spotiflac_android/providers/extension_provider.dart';
 import 'package:spotiflac_android/providers/library_collections_provider.dart';
 import 'package:spotiflac_android/providers/settings_provider.dart';
 import 'package:spotiflac_android/services/backup_service.dart';
@@ -25,6 +26,7 @@ class _BackupRestorePageState extends ConsumerState<BackupRestorePage> {
 
   bool _isExporting = false;
   bool _isImporting = false;
+  bool _includeSecrets = false;
 
   bool get _isBusy => _isExporting || _isImporting;
 
@@ -41,12 +43,16 @@ class _BackupRestorePageState extends ConsumerState<BackupRestorePage> {
       );
       final collections = await collectionsNotifier.exportCollections();
       final covers = await collectionsNotifier.exportPlaylistCovers();
+      final extensions = await ref
+          .read(extensionProvider.notifier)
+          .exportBackup(includeSecrets: _includeSecrets);
 
       final envelope = BackupService.buildEnvelope(
         settings: settings,
         history: history,
         collections: collections,
         playlistCovers: covers,
+        extensions: extensions,
       );
 
       final file = await BackupService.writeBackupFile(envelope);
@@ -117,10 +123,26 @@ class _BackupRestorePageState extends ConsumerState<BackupRestorePage> {
             coverImages: bundle.playlistCovers,
           );
 
+      ExtensionRestoreResult? extResult;
+      if (bundle.hasExtensions) {
+        extResult = await ref
+            .read(extensionProvider.notifier)
+            .restoreFromBackup(bundle.extensions);
+      }
+
+      final message = StringBuffer(l10n.backupRestored)
+        ..write('\n')
+        ..write(l10n.backupRestoreRestartHint);
+      if (extResult != null && extResult.failed > 0) {
+        message
+          ..write('\n')
+          ..write(l10n.backupExtensionsRestoreFailed(extResult.failed));
+      }
+
       messenger.showSnackBar(
         SnackBar(
-          content: Text('${l10n.backupRestored}\n${l10n.backupRestoreRestartHint}'),
-          duration: const Duration(seconds: 5),
+          content: Text(message.toString()),
+          duration: const Duration(seconds: 6),
         ),
       );
     } catch (e, stack) {
@@ -182,6 +204,13 @@ class _BackupRestorePageState extends ConsumerState<BackupRestorePage> {
                     bundle.favoriteArtistCount,
                   ),
                 ),
+              if (bundle.extensionCount > 0)
+                _ContentRow(
+                  icon: Icons.extension_outlined,
+                  label: l10n.backupContentsExtensions(
+                    bundle.extensionCount,
+                  ),
+                ),
             ],
           ),
           actions: [
@@ -259,6 +288,20 @@ class _BackupRestorePageState extends ConsumerState<BackupRestorePage> {
                     buttonIcon: Icons.ios_share,
                     isBusy: _isExporting,
                     onPressed: _isBusy ? null : _createBackup,
+                    extra: Padding(
+                      padding: const EdgeInsets.only(top: 4, bottom: 4),
+                      child: SwitchListTile(
+                        contentPadding: EdgeInsets.zero,
+                        value: _includeSecrets,
+                        onChanged: _isBusy
+                            ? null
+                            : (value) =>
+                                  setState(() => _includeSecrets = value),
+                        title: Text(l10n.backupIncludeSecrets),
+                        subtitle: Text(l10n.backupIncludeSecretsDescription),
+                        isThreeLine: true,
+                      ),
+                    ),
                   ),
                   const SizedBox(height: 16),
                   _ActionCard(
@@ -288,6 +331,7 @@ class _ActionCard extends StatelessWidget {
   final IconData buttonIcon;
   final bool isBusy;
   final VoidCallback? onPressed;
+  final Widget? extra;
 
   const _ActionCard({
     required this.icon,
@@ -297,6 +341,7 @@ class _ActionCard extends StatelessWidget {
     required this.buttonIcon,
     required this.isBusy,
     required this.onPressed,
+    this.extra,
   });
 
   @override
@@ -333,8 +378,8 @@ class _ActionCard extends StatelessWidget {
               color: colorScheme.onSurfaceVariant,
             ),
           ),
-          const SizedBox(height: 16),
-          FilledButton.icon(
+          ?extra,
+          const SizedBox(height: 16),          FilledButton.icon(
             onPressed: onPressed,
             icon: isBusy
                 ? const SizedBox(

lib/services/backup_service.dart

@@ -25,6 +25,9 @@ class BackupBundle {
   /// Playlist cover images keyed by playlist id: `{ id: { ext, data } }`.
   final Map<String, dynamic> playlistCovers;
 
+  /// Extensions section: `{ registry_url, items: [ {id, version, enabled, settings} ] }`.
+  final Map<String, dynamic> extensions;
+
   const BackupBundle({
     required this.formatVersion,
     required this.appVersion,
@@ -33,6 +36,7 @@ class BackupBundle {
     required this.history,
     required this.collections,
     required this.playlistCovers,
+    required this.extensions,
   });
 
   bool get hasSettings => settings != null && settings!.isNotEmpty;
@@ -49,13 +53,21 @@ class BackupBundle {
   int get playlistCount => _collectionListCount('playlists');
   int get favoriteArtistCount => _collectionListCount('favoriteArtists');
 
+  int get extensionCount {
+    final items = extensions['items'];
+    return items is List ? items.length : 0;
+  }
+
+  bool get hasExtensions => extensionCount > 0;
+
   bool get isEmpty =>
       !hasSettings &&
       historyCount == 0 &&
       likedCount == 0 &&
       wishlistCount == 0 &&
       playlistCount == 0 &&
-      favoriteArtistCount == 0;
+      favoriteArtistCount == 0 &&
+      extensionCount == 0;
 }
 
 /// Builds and parses SpotiFLAC backup files (a single JSON document containing
@@ -73,6 +85,7 @@ class BackupService {
     required List<Map<String, dynamic>> history,
     required Map<String, dynamic> collections,
     required Map<String, dynamic> playlistCovers,
+    required Map<String, dynamic> extensions,
   }) {
     return {
       'magic': magic,
@@ -85,6 +98,7 @@ class BackupService {
         'history': history,
         'collections': collections,
         'playlist_covers': playlistCovers,
+        'extensions': extensions,
       },
     };
   }
@@ -165,6 +179,11 @@ class BackupService {
         ? Map<String, dynamic>.from(coversRaw)
         : <String, dynamic>{};
 
+    final extensionsRaw = data['extensions'];
+    final extensions = extensionsRaw is Map
+        ? Map<String, dynamic>.from(extensionsRaw)
+        : <String, dynamic>{};
+
     return BackupBundle(
       formatVersion: (root['format_version'] as num?)?.toInt() ?? 1,
       appVersion: root['app_version'] as String? ?? '',
@@ -173,6 +192,7 @@ class BackupService {
       history: history,
       collections: collections,
       playlistCovers: playlistCovers,
+      extensions: extensions,
     );
   }
 }