Handling some warnings and proper disposals of shells etc.

AGENTS.md

@@ -104,6 +104,7 @@ private string searchQuery = string.Empty;
 - WinUI 3 auto-converts bool to Visibility: `Visibility="{x:Bind IsVisible, Mode=OneWay}"`
 - Use XamlHelpers for complex conversions: `{x:Bind helpers:XamlHelpers.ReverseBoolToVisibilityConverter(Prop)}`
 - `x:Bind` does not implicitly convert `double` to `GridLength`; when binding `RowDefinition.Height` or `ColumnDefinition.Width`, use a `XamlHelpers` method such as `DoubleToGridLength(...)`
+- For `ComboBox` controls in XAML, never use `DisplayMemberPath` or `SelectedValuePath`; use a typed `ItemTemplate` and bind `SelectedItem` explicitly, preferably with `x:Bind`
 
 ## Localization
 

Wino.Calendar.ViewModels/CalendarAppShellViewModel.cs

@@ -198,6 +198,26 @@ public partial class CalendarAppShellViewModel : CalendarBaseViewModel,
         _calendarPageViewModel.CleanupForShellDeactivation();
     }
 
+    public void PrepareForShellShutdown()
+    {
+        DetachRuntimeSubscriptions();
+        PreferencesService.PreferenceChanged -= PreferencesServiceChanged;
+
+        if (_hasRegisteredPersistentRecipients)
+        {
+            UnregisterRecipients();
+            _hasRegisteredPersistentRecipients = false;
+        }
+
+        DateNavigationHeaderItems.Clear();
+        SelectedDateNavigationHeaderIndex = -1;
+        SelectedMenuItemIndex = -1;
+        MenuItems?.Clear();
+        FooterItems?.Clear();
+        AccountCalendarStateService.ClearGroupedAccountCalendars();
+        _calendarPageViewModel.CleanupForShellDeactivation();
+    }
+
     private void AttachRuntimeSubscriptions()
     {
         if (_runtimeSubscriptionsAttached)

Wino.Mail.ViewModels/MailAppShellViewModel.cs

@@ -30,7 +30,6 @@ namespace Wino.Mail.ViewModels;
 
 public partial class MailAppShellViewModel : MailBaseViewModel,
     IMailShellClient,
-    IRecipient<AccountCreatedMessage>,
     IRecipient<MailtoProtocolMessageRequested>,
     IRecipient<RefreshUnreadCountsMessage>,
     IRecipient<AccountsMenuRefreshRequested>,
@@ -236,14 +235,14 @@ public partial class MailAppShellViewModel : MailBaseViewModel,
 
         var activationContext = parameters as ShellModeActivationContext;
         var shouldRunStartupFlows = activationContext?.IsInitialActivation ?? true;
-        var hasExistingMenuItems = MenuItems?.Any() == true;
+        var hasExistingAccountMenuItems = MenuItems?.OfType<IAccountMenuItem>().Any() == true;
 
         PreferencesService.PreferenceChanged -= PreferencesServiceChanged;
         PreferencesService.PreferenceChanged += PreferencesServiceChanged;
 
         await CreateFooterItemsAsync(true);
 
-        if (!hasExistingMenuItems)
+        if (!hasExistingAccountMenuItems)
         {
             await RecreateMenuItemsAsync();
         }
@@ -278,6 +277,24 @@ public partial class MailAppShellViewModel : MailBaseViewModel,
         PreferencesService.PreferenceChanged -= PreferencesServiceChanged;
     }
 
+    public void PrepareForShellShutdown()
+    {
+        PreferencesService.PreferenceChanged -= PreferencesServiceChanged;
+
+        if (_hasRegisteredPersistentRecipients)
+        {
+            UnregisterRecipients();
+            _hasRegisteredPersistentRecipients = false;
+        }
+
+        latestSelectedAccountMenuItem = null;
+        SelectedMenuItem = null;
+
+        MenuItems?.Clear();
+        MenuItems?.Add(CreateMailMenuItem);
+        FooterItems?.Clear();
+    }
+
     private async Task ShowWhatIsNewIfNeededAsync()
     {
         if (!_updateManager.ShouldShowUpdateNotes())
@@ -1159,7 +1176,6 @@ public partial class MailAppShellViewModel : MailBaseViewModel,
 
         Messenger.Register<AccountRemovedMessage>(this);
         Messenger.Register<AccountUpdatedMessage>(this);
-        Messenger.Register<AccountCreatedMessage>(this);
         Messenger.Register<MailtoProtocolMessageRequested>(this);
         Messenger.Register<RefreshUnreadCountsMessage>(this);
         Messenger.Register<AccountsMenuRefreshRequested>(this);
@@ -1177,7 +1193,6 @@ public partial class MailAppShellViewModel : MailBaseViewModel,
 
         Messenger.Unregister<AccountRemovedMessage>(this);
         Messenger.Unregister<AccountUpdatedMessage>(this);
-        Messenger.Unregister<AccountCreatedMessage>(this);
         Messenger.Unregister<MailtoProtocolMessageRequested>(this);
         Messenger.Unregister<RefreshUnreadCountsMessage>(this);
         Messenger.Unregister<AccountsMenuRefreshRequested>(this);
@@ -1191,6 +1206,19 @@ public partial class MailAppShellViewModel : MailBaseViewModel,
 
     public async void Receive(AccountRemovedMessage message)
     {
+        var remainingAccounts = await _accountService.GetAccountsAsync().ConfigureAwait(false);
+        if (!remainingAccounts.Any())
+        {
+            latestSelectedAccountMenuItem = null;
+            await ExecuteUIThread(() =>
+            {
+                SelectedMenuItem = null;
+                MenuItems?.Clear();
+                MenuItems?.Add(CreateMailMenuItem);
+            });
+            return;
+        }
+
         if (latestSelectedAccountMenuItem?.HoldingAccounts?.Any(a => a.Id == message.Account.Id) == true)
         {
             latestSelectedAccountMenuItem = null;
@@ -1201,9 +1229,6 @@ public partial class MailAppShellViewModel : MailBaseViewModel,
         await RestoreSelectedAccountAfterMenuRefreshAsync(false);
     }
 
-    public async void Receive(AccountCreatedMessage message)
-        => await HandleAccountCreatedAsync(message.Account);
-
     public async Task HandleAccountCreatedAsync(MailAccount createdAccount)
     {
         latestSelectedAccountMenuItem = null;

Wino.Mail.WinUI/App.xaml.cs

@@ -10,6 +10,7 @@ using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Toolkit.Uwp.Notifications;
 using Microsoft.UI.Dispatching;
 using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Media.Animation;
 using Microsoft.Windows.AppLifecycle;
 using Microsoft.Windows.AppNotifications;
 using MimeKit.Cryptography;
@@ -192,7 +193,7 @@ public partial class App : WinoApplication,
         if (welcomeWindow == null)
             return;
 
-        windowManager.HideWindow(WinoWindowKind.Shell);
+        CloseShellWindowIfPresent();
         await ActivateWindowAsync(welcomeWindow);
     }
 
@@ -232,6 +233,16 @@ public partial class App : WinoApplication,
         welcomeWindow.Close();
     }
 
+    private void CloseShellWindowIfPresent()
+    {
+        var windowManager = Services.GetRequiredService<IWinoWindowManager>();
+        if (windowManager.GetWindow(WinoWindowKind.Shell) is not ShellWindow shellWindow)
+            return;
+
+        shellWindow.PrepareForClose();
+        shellWindow.Close();
+    }
+
     private async Task ActivateWindowAsync(WindowEx window)
     {
         var windowManager = Services.GetRequiredService<IWinoWindowManager>();
@@ -792,8 +803,9 @@ public partial class App : WinoApplication,
             }
             else
             {
-                Services.GetRequiredService<INavigationService>()
-                    .Navigate(WinoPage.WelcomeHostPage, null, NavigationReferenceFrame.ShellFrame, NavigationTransitionType.None);
+                rootFrame.BackStack.Clear();
+                rootFrame.ForwardStack.Clear();
+                rootFrame.Navigate(typeof(WelcomeHostPage), null, new SuppressNavigationTransitionInfo());
             }
         }
 
@@ -926,8 +938,8 @@ public partial class App : WinoApplication,
             // All accounts removed — go back to welcome wizard from step 1
             Services.GetRequiredService<WelcomeWizardContext>().Reset();
             StopAutoSynchronizationLoop();
+            CloseShellWindowIfPresent();
             CreateWelcomeWindow();
-            windowManager.HideWindow(WinoWindowKind.Shell);
             if (MainWindow != null)
                 await ActivateWindowAsync(MainWindow);
         });

Wino.Mail.WinUI/Controls/AppModeFooterSwitcherControl.xaml

@@ -9,22 +9,22 @@
     Loaded="ControlLoaded"
     SelectionChanged="ModeSegmentedControlSelectionChanged"
     Unloaded="ControlUnloaded">
-    <controls:SegmentedItem Padding="0" ToolTipService.ToolTip="{x:Bind domain:Translator.KeyboardShortcuts_ModeMail, Mode=OneWay}">
+    <controls:SegmentedItem Padding="0" ToolTipService.ToolTip="{x:Bind domain:Translator.KeyboardShortcuts_ModeMail}">
         <controls:SegmentedItem.Icon>
             <SymbolIcon Symbol="Mail" />
         </controls:SegmentedItem.Icon>
     </controls:SegmentedItem>
-    <controls:SegmentedItem Padding="0" ToolTipService.ToolTip="{x:Bind domain:Translator.KeyboardShortcuts_ModeCalendar, Mode=OneWay}">
+    <controls:SegmentedItem Padding="0" ToolTipService.ToolTip="{x:Bind domain:Translator.KeyboardShortcuts_ModeCalendar}">
         <controls:SegmentedItem.Icon>
             <SymbolIcon Symbol="Calendar" />
         </controls:SegmentedItem.Icon>
     </controls:SegmentedItem>
-    <controls:SegmentedItem Padding="0" ToolTipService.ToolTip="{x:Bind domain:Translator.ContactsPage_Title, Mode=OneWay}">
+    <controls:SegmentedItem Padding="0" ToolTipService.ToolTip="{x:Bind domain:Translator.ContactsPage_Title}">
         <controls:SegmentedItem.Icon>
             <FontIcon FontFamily="{StaticResource SymbolThemeFontFamily}" Glyph="&#xE716;" />
         </controls:SegmentedItem.Icon>
     </controls:SegmentedItem>
-    <controls:SegmentedItem Padding="0" ToolTipService.ToolTip="{x:Bind domain:Translator.MenuSettings, Mode=OneWay}">
+    <controls:SegmentedItem Padding="0" ToolTipService.ToolTip="{x:Bind domain:Translator.MenuSettings}">
         <controls:SegmentedItem.Icon>
             <SymbolIcon Symbol="Setting" />
         </controls:SegmentedItem.Icon>

Wino.Mail.WinUI/Controls/EditorTabbedCommandBarControl.xaml

@@ -52,6 +52,10 @@
             </StackPanel>
         </DataTemplate>
 
+        <DataTemplate x:Key="ParagraphStyleOptionTemplate" x:DataType="mail:EditorParagraphStyleOption">
+            <TextBlock Text="{x:Bind Name}" />
+        </DataTemplate>
+
     </UserControl.Resources>
 
     <toolkit:TabbedCommandBar>
@@ -231,7 +235,7 @@
                                 x:Name="ParagraphStyleComboBox"
                                 Grid.Column="1"
                                 MinWidth="104"
-                                DisplayMemberPath="Name"
+                                ItemTemplate="{StaticResource ParagraphStyleOptionTemplate}"
                                 PlaceholderText="Paragraph"
                                 SelectionChanged="ParagraphStyleComboBox_SelectionChanged"
                                 Style="{StaticResource CompactComboBoxStyle}" />

Wino.Mail.WinUI/Dialogs/MessageSourceDialog.xaml

@@ -30,7 +30,7 @@
                 FontFamily="Consolas"
                 FontSize="12"
                 IsTextSelectionEnabled="True"
-                Text="{x:Bind MessageSource, Mode=OneWay}"
+                Text="{x:Bind MessageSource}"
                 TextWrapping="Wrap" />
         </Border>
     </ScrollViewer>

Wino.Mail.WinUI/Dialogs/MoveMailDialog.xaml

@@ -61,7 +61,7 @@
             CanDragItems="False"
             CanReorderItems="False"
             ItemTemplate="{StaticResource FolderStructureMenuFlyoutItemTemplate}"
-            ItemsSource="{x:Bind FolderList, Mode=OneWay}"
+            ItemsSource="{x:Bind FolderList}"
             SelectedItem="{x:Bind SelectedFolder, Mode=TwoWay}"
             SelectionMode="Single" />
     </Grid>

Wino.Mail.WinUI/Dialogs/NewAccountDialog.xaml

@@ -163,7 +163,7 @@
 
             <ComboBox
                 Grid.Row="4"
-                Header="{x:Bind domain:Translator.ImapCalDavSettingsPage_CalendarModeHeader, Mode=OneWay}"
+                Header="{x:Bind domain:Translator.ImapCalDavSettingsPage_CalendarModeHeader}"
                 ItemsSource="{x:Bind CalendarModeOptions, Mode=OneWay}"
                 SelectedIndex="{x:Bind SelectedCalendarModeIndex, Mode=TwoWay}" />
 

Wino.Mail.WinUI/Dialogs/SingleCalendarPickerDialog.xaml

@@ -28,13 +28,13 @@
     <StackPanel Margin="0,8,0,0" Spacing="12">
         <TextBlock
             Foreground="{ThemeResource TextFillColorSecondaryBrush}"
-            Text="{x:Bind domain:Translator.CalendarEventCompose_DefaultCalendarHint, Mode=OneWay}"
+            Text="{x:Bind domain:Translator.CalendarEventCompose_DefaultCalendarHint}"
             TextWrapping="WrapWholeWords" />
 
         <HyperlinkButton
             HorizontalAlignment="Left"
             Click="OpenCalendarSettingsClicked"
-            Content="{x:Bind domain:Translator.CalendarEventCompose_DefaultCalendarSettingsLink, Mode=OneWay}"
+            Content="{x:Bind domain:Translator.CalendarEventCompose_DefaultCalendarSettingsLink}"
             Padding="0" />
 
         <ScrollViewer MaxHeight="400">
@@ -67,7 +67,7 @@
                                                 Width="14"
                                                 Height="14"
                                                 VerticalAlignment="Center"
-                                                Fill="{x:Bind helpers:XamlHelpers.GetSolidColorBrushFromHex(BackgroundColorHex), Mode=OneWay}" />
+                                                Fill="{x:Bind helpers:XamlHelpers.GetSolidColorBrushFromHex(BackgroundColorHex)}" />
 
                                             <TextBlock
                                                 Grid.Column="1"

Wino.Mail.WinUI/Properties/launchSettings.json

@@ -3,7 +3,7 @@
     "Wino.Mail.WinUI (Package)": {
       "commandName": "MsixPackage",
       "doNotLaunchApp": false,
-      "nativeDebugging": true
+      "nativeDebugging": false
     },
     "Wino.Mail.WinUI (Unpackaged)": {
       "commandName": "Project"

Wino.Mail.WinUI/ShellWindow.xaml

@@ -143,17 +143,6 @@
                                                 </LinearGradientBrush>
                                             </Border.Background>
                                             <StackPanel Spacing="4">
-                                                <Border
-                                                    Width="40"
-                                                    Height="40"
-                                                    HorizontalAlignment="Left"
-                                                    Background="{ThemeResource AccentFillColorDefaultBrush}"
-                                                    CornerRadius="20">
-                                                    <FontIcon
-                                                        FontSize="18"
-                                                        Foreground="White"
-                                                        Glyph="&#xE77B;" />
-                                                </Border>
                                                 <TextBlock
                                                     Margin="0,8,0,0"
                                                     Style="{StaticResource SubtitleTextBlockStyle}"

Wino.Mail.WinUI/ShellWindow.xaml.cs

@@ -34,6 +34,7 @@ public sealed partial class ShellWindow : WindowEx, IWinoShellWindow,
     IRecipient<WinoAccountProfileUpdatedMessage>,
     IRecipient<WinoAccountProfileDeletedMessage>
 {
+    private bool _allowClose;
     public IStatePersistanceService StatePersistanceService { get; } = WinoApplication.Current.Services.GetService<IStatePersistanceService>() ?? throw new Exception("StatePersistanceService not registered in DI container.");
     public IPreferencesService PreferencesService { get; } = WinoApplication.Current.Services.GetService<IPreferencesService>() ?? throw new Exception("PreferencesService not registered in DI container.");
     public INavigationService NavigationService { get; } = WinoApplication.Current.Services.GetService<INavigationService>() ?? throw new Exception("NavigationService not registered in DI container.");
@@ -354,7 +355,7 @@ public sealed partial class ShellWindow : WindowEx, IWinoShellWindow,
 
     private void OnAppWindowClosing(object sender, Microsoft.UI.Windowing.AppWindowClosingEventArgs e)
     {
-        if ((Application.Current as App)?.IsExiting == true)
+        if (_allowClose || (Application.Current as App)?.IsExiting == true)
             return;
 
         e.Cancel = true;
@@ -362,10 +363,27 @@ public sealed partial class ShellWindow : WindowEx, IWinoShellWindow,
         windowManager?.HideWindow(this);
     }
 
+    public void PrepareForClose()
+    {
+        if (MainShellFrame.Content is WinoAppShell shellPage)
+        {
+            shellPage.PrepareForWindowClose();
+        }
+
+        _allowClose = true;
+    }
+
     private void OnWindowClosed(object sender, WindowEventArgs e)
     {
+        Closed -= OnWindowClosed;
         AppWindow.Closing -= OnAppWindowClosing;
         StatePersistanceService.StatePropertyChanged -= StatePersistenceServiceChanged;
+
+        if (MainShellFrame.Content is WinoAppShell shellPage)
+        {
+            shellPage.PrepareForWindowClose();
+        }
+
         UnregisterRecipients();
     }
 

Wino.Mail.WinUI/ViewModels/ContactsShellClient.cs

@@ -34,6 +34,12 @@ public sealed class ContactsShellClient(INavigationService navigationService) :
     public void Activate(ShellModeActivationContext activationContext)
     {
         OnNavigatedTo(NavigationMode.New, activationContext);
+
+        if (MenuItems?.Count == 0)
+        {
+            MenuItems.Add(_newContactMenuItem);
+        }
+
         navigationService.Navigate(WinoPage.ContactsPage, null, NavigationReferenceFrame.InnerShellFrame);
     }
 
@@ -42,6 +48,16 @@ public sealed class ContactsShellClient(INavigationService navigationService) :
         OnNavigatedFrom(NavigationMode.New, null!);
     }
 
+    public void PrepareForShellShutdown()
+    {
+        SelectedMenuItem = null;
+        if (MenuItems != null)
+        {
+            MenuItems.Clear();
+            MenuItems.Add(_newContactMenuItem);
+        }
+    }
+
     public Task HandleNavigationItemInvokedAsync(IMenuItem? menuItem)
     {
         if (menuItem is NewContactMenuItem)

Wino.Mail.WinUI/ViewModels/SettingsShellClient.cs

@@ -57,6 +57,18 @@ public partial class SettingsShellClient(INavigationService navigationService) :
     {
     }
 
+    public void PrepareForShellShutdown()
+    {
+        if (_hasRegisteredPersistentRecipients)
+        {
+            UnregisterRecipients();
+            _hasRegisteredPersistentRecipients = false;
+        }
+
+        SelectedMenuItem = null;
+        MenuItems?.Clear();
+    }
+
     public Task HandleNavigationItemInvokedAsync(IMenuItem? menuItem)
     {
         if (menuItem is not SettingsShellPageMenuItem settingsMenuItem)

Wino.Mail.WinUI/Views/Calendar/CalendarEventComposePage.xaml

@@ -447,7 +447,7 @@
                                                 Foreground="{ThemeResource TextFillColorSecondaryBrush}"
                                                 Text="{x:Bind Email}"
                                                 TextTrimming="CharacterEllipsis"
-                                                Visibility="{x:Bind HasDistinctDisplayName, Mode=OneWay}" />
+                                                Visibility="{x:Bind HasDistinctDisplayName}" />
                                         </StackPanel>
 
                                         <Button

Wino.Mail.WinUI/Views/Settings/AliasManagementPage.xaml

@@ -14,6 +14,7 @@
     xmlns:muxc="using:Microsoft.UI.Xaml.Controls"
     xmlns:reader="using:Wino.Core.Domain.Models.Reader"
     xmlns:toolkitExt="using:CommunityToolkit.WinUI"
+    xmlns:x509="using:System.Security.Cryptography.X509Certificates"
     x:Name="root"
     mc:Ignorable="d">
 
@@ -65,18 +66,23 @@
                     Grid.Column="2"
                     Click="SetAliasPrimary_Click"
                     CommandParameter="{x:Bind}"
-                    IsChecked="{x:Bind IsPrimary, Mode=OneWay}" />
+                    IsChecked="{x:Bind IsPrimary}" />
 
 
                 <ComboBox
                     Grid.Column="3"
                     HorizontalAlignment="Center"
-                    DisplayMemberPath="Subject"
                     DropDownClosed="SigningCertificateDropDownClosed"
                     IsEnabled="{x:Bind IsSmimeEncryptionEnabled}"
-                    ItemsSource="{x:Bind Certificates, Mode=OneWay}"
+                    ItemsSource="{x:Bind Certificates}"
                     PlaceholderText="{x:Bind domain:Translator.SettingsSignatureAndEncryption_SigningCertificatePlaceholder}"
-                    SelectedItem="{Binding SelectedSigningCertificate, Mode=TwoWay}" />
+                    SelectedItem="{x:Bind SelectedSigningCertificate, Mode=TwoWay}">
+                    <ComboBox.ItemTemplate>
+                        <DataTemplate x:DataType="x509:X509Certificate2">
+                            <TextBlock Text="{x:Bind Subject}" />
+                        </DataTemplate>
+                    </ComboBox.ItemTemplate>
+                </ComboBox>
 
                 <CheckBox
                     Grid.Column="4"

Wino.Mail.WinUI/Views/Settings/SignatureAndEncryptionPage.xaml

@@ -65,17 +65,17 @@
                                             <ColumnDefinition Width="120" />
                                             <ColumnDefinition Width="*" />
                                         </Grid.ColumnDefinitions>
-                                        <TextBlock Grid.Column="1" Text="{x:Bind Subject, Mode=OneWay}" />
+                                        <TextBlock Grid.Column="1" Text="{x:Bind Subject}" />
                                         <TextBlock
                                             Grid.Column="2"
                                             FontSize="10"
                                             Foreground="Gray"
-                                            Text="{x:Bind NotAfter, Mode=OneWay}" />
+                                            Text="{x:Bind NotAfter}" />
                                         <TextBlock
                                             Grid.Column="3"
                                             FontSize="10"
                                             Foreground="Gray"
-                                            Text="{x:Bind Thumbprint, Mode=OneWay}" />
+                                            Text="{x:Bind Thumbprint}" />
                                     </Grid>
                                 </DataTemplate>
                             </ListView.ItemTemplate>
@@ -146,17 +146,17 @@
                                             <ColumnDefinition Width="120" />
                                             <ColumnDefinition Width="*" />
                                         </Grid.ColumnDefinitions>
-                                        <TextBlock Grid.Column="1" Text="{x:Bind Subject, Mode=OneWay}" />
+                                        <TextBlock Grid.Column="1" Text="{x:Bind Subject}" />
                                         <TextBlock
                                             Grid.Column="2"
                                             FontSize="10"
                                             Foreground="Gray"
-                                            Text="{x:Bind NotAfter, Mode=OneWay}" />
+                                            Text="{x:Bind NotAfter}" />
                                         <TextBlock
                                             Grid.Column="3"
                                             FontSize="10"
                                             Foreground="Gray"
-                                            Text="{x:Bind Thumbprint, Mode=OneWay}" />
+                                            Text="{x:Bind Thumbprint}" />
                                     </Grid>
                                 </DataTemplate>
                             </ListView.ItemTemplate>

Wino.Mail.WinUI/Views/Settings/WinoAccountManagementPage.xaml

@@ -21,23 +21,23 @@
                 </controls:SettingsCard.HeaderIcon>
                 <controls:SettingsCard.Header>
                     <StackPanel Spacing="8">
-                        <TextBlock FontWeight="SemiBold" Text="{x:Bind domain:Translator.GetTranslatedString(NameKey), Mode=OneWay}" />
+                        <TextBlock FontWeight="SemiBold" Text="{x:Bind domain:Translator.GetTranslatedString(NameKey)}" />
                         <TextBlock
                             Foreground="{ThemeResource TextFillColorSecondaryBrush}"
                             Style="{StaticResource BodyTextBlockStyle}"
-                            Text="{x:Bind domain:Translator.GetTranslatedString(DescriptionKey), Mode=OneWay}"
+                            Text="{x:Bind domain:Translator.GetTranslatedString(DescriptionKey)}"
                             TextWrapping="WrapWholeWords" />
                         <TextBlock
                             Foreground="{ThemeResource TextFillColorSecondaryBrush}"
                             Style="{StaticResource CaptionTextBlockStyle}"
-                            Text="{x:Bind domain:Translator.GetTranslatedString(KeywordsKey), Mode=OneWay}"
+                            Text="{x:Bind domain:Translator.GetTranslatedString(KeywordsKey)}"
                             TextWrapping="WrapWholeWords" />
                         <StackPanel
                             Margin="0,4,0,0"
                             Orientation="Horizontal"
                             Spacing="12">
                             <Button
-                                Command="{x:Bind PurchaseCommand, Mode=OneWay}"
+                                Command="{x:Bind PurchaseCommand}"
                                 CommandParameter="{x:Bind}"
                                 Content="{x:Bind domain:Translator.Buttons_Purchase}"
                                 Style="{StaticResource AccentButtonStyle}" />
@@ -59,7 +59,7 @@
                 </controls:SettingsExpander.HeaderIcon>
                 <controls:SettingsExpander.Header>
                     <StackPanel Orientation="Horizontal" Spacing="8">
-                        <TextBlock FontWeight="SemiBold" Text="{x:Bind domain:Translator.GetTranslatedString(NameKey), Mode=OneWay}" />
+                        <TextBlock FontWeight="SemiBold" Text="{x:Bind domain:Translator.GetTranslatedString(NameKey)}" />
                         <Border
                             Padding="8,2"
                             Background="{ThemeResource SystemAccentColor}"
@@ -88,7 +88,7 @@
                             Text="{x:Bind RenewalText, Mode=OneWay}" />
                     </StackPanel>
                 </controls:SettingsExpander.Description>
-                <HyperlinkButton Command="{x:Bind ManageCommand, Mode=OneWay}" Content="{x:Bind domain:Translator.Buttons_Manage}" />
+                <HyperlinkButton Command="{x:Bind ManageCommand}" Content="{x:Bind domain:Translator.Buttons_Manage}" />
                 <controls:SettingsExpander.Items>
                     <controls:SettingsCard HorizontalContentAlignment="Stretch">
                         <controls:SettingsCard.Header>
@@ -137,16 +137,16 @@
                 </controls:SettingsCard.HeaderIcon>
                 <controls:SettingsCard.Header>
                     <StackPanel Spacing="8">
-                        <TextBlock FontWeight="SemiBold" Text="{x:Bind domain:Translator.GetTranslatedString(NameKey), Mode=OneWay}" />
+                        <TextBlock FontWeight="SemiBold" Text="{x:Bind domain:Translator.GetTranslatedString(NameKey)}" />
                         <TextBlock
                             Foreground="{ThemeResource TextFillColorSecondaryBrush}"
                             Style="{StaticResource BodyTextBlockStyle}"
-                            Text="{x:Bind domain:Translator.GetTranslatedString(DescriptionKey), Mode=OneWay}"
+                            Text="{x:Bind domain:Translator.GetTranslatedString(DescriptionKey)}"
                             TextWrapping="WrapWholeWords" />
                         <TextBlock
                             Foreground="{ThemeResource TextFillColorSecondaryBrush}"
                             Style="{StaticResource CaptionTextBlockStyle}"
-                            Text="{x:Bind domain:Translator.GetTranslatedString(KeywordsKey), Mode=OneWay}"
+                            Text="{x:Bind domain:Translator.GetTranslatedString(KeywordsKey)}"
                             TextWrapping="WrapWholeWords" />
                         <Border
                             Padding="12,4"

Wino.Mail.WinUI/Views/WinoAppShell.xaml.cs

@@ -23,7 +23,10 @@ using Wino.Core.Domain.Models.Calendar;
 using Wino.Core.Domain.Models.Folders;
 using Wino.Core.Domain.Models.MailItem;
 using Wino.Core.Domain.Models.Navigation;
+using Wino.Calendar.ViewModels;
+using Wino.Mail.ViewModels;
 using Wino.Mail.ViewModels.Data;
+using Wino.Mail.WinUI.ViewModels;
 using Wino.Mail.WinUI.Controls;
 using Wino.MenuFlyouts;
 using Wino.MenuFlyouts.Context;
@@ -49,6 +52,7 @@ public sealed partial class WinoAppShell : Views.Abstract.WinoAppShellAbstract,
     private WinoApplicationMode? _activeMode;
     private bool _isSyncingNavigationViewSelection;
     private bool _isSynchronizingVisibleDateRangeCalendar;
+    private bool _isPreparedForWindowClose;
 
     public WinoAppShell()
     {
@@ -98,10 +102,33 @@ public sealed partial class WinoAppShell : Views.Abstract.WinoAppShellAbstract,
     protected override void OnNavigatedFrom(NavigationEventArgs e)
     {
         base.OnNavigatedFrom(e);
-        DeactivateCurrentMode();
+
+        if (!_isPreparedForWindowClose)
+        {
+            DeactivateCurrentMode();
+            DetachLifetimeSubscriptions();
+        }
+
         Bindings.StopTracking();
     }
 
+    public void PrepareForWindowClose()
+    {
+        if (_isPreparedForWindowClose)
+            return;
+
+        _isPreparedForWindowClose = true;
+
+        DeactivateAllShellClients();
+        WeakReferenceMessenger.Default.Unregister<LanguageChanged>(this);
+        UnregisterRecipients();
+        DetachLifetimeSubscriptions();
+        Bindings.StopTracking();
+
+        navigationView.MenuItemsSource = null;
+        CalendarHostListView.ItemsSource = null;
+    }
+
     private void OnLoaded(object sender, RoutedEventArgs e)
     {
         UpdateNavigationPaneLayout(navigationView.DisplayMode);
@@ -155,6 +182,44 @@ public sealed partial class WinoAppShell : Views.Abstract.WinoAppShellAbstract,
         }
     }
 
+    private void DeactivateAllShellClients()
+    {
+        ViewModel.StatePersistenceService.IsReadingMail = false;
+        ViewModel.StatePersistenceService.IsEventDetailsVisible = false;
+
+        ViewModel.MailClient.Deactivate();
+        ViewModel.CalendarClient.Deactivate();
+
+        if (ViewModel.GetClient(WinoApplicationMode.Contacts) is ContactsShellClient contactsClient)
+        {
+            contactsClient.PrepareForShellShutdown();
+        }
+
+        if (ViewModel.GetClient(WinoApplicationMode.Settings) is SettingsShellClient settingsClient)
+        {
+            settingsClient.PrepareForShellShutdown();
+        }
+
+        if (ViewModel.MailClient is MailAppShellViewModel mailClient)
+        {
+            mailClient.PrepareForShellShutdown();
+        }
+
+        if (ViewModel.CalendarClient is CalendarAppShellViewModel calendarClient)
+        {
+            calendarClient.PrepareForShellShutdown();
+        }
+    }
+
+    private void DetachLifetimeSubscriptions()
+    {
+        ViewModel.MailClient.PropertyChanged -= MailClientPropertyChanged;
+        ViewModel.CalendarClient.PropertyChanged -= CalendarClientPropertyChanged;
+        ViewModel.PropertyChanged -= ViewModelPropertyChanged;
+        ViewModel.PreferencesService.PreferenceChanged -= PreferencesServiceChanged;
+        ViewModel.StatePersistenceService.StatePropertyChanged -= StatePersistenceServiceChanged;
+    }
+
     private void ResetShellModeNavigationState()
     {
         InnerShellFrame.BackStack.Clear();