Some more cleanup.

Wino.Mail.WinUI/App.xaml.cs

@@ -231,6 +231,7 @@ public partial class App : WinoApplication,
         if (windowManager.GetWindow(WinoWindowKind.Welcome) is not WelcomeWindow welcomeWindow)
             return;
 
+        welcomeWindow.PrepareForClose();
         welcomeWindow.AllowClose();
         welcomeWindow.Close();
     }

Wino.Mail.WinUI/Assets/UpdateNotes/vnext.json

@@ -1,35 +1,35 @@
 {
     "sections": [
         {
-            "title": "# Wino Calendar is here!",
+            "title": "Wino Calendar is here!",
             "description": "You can now create local or remote CalDAV-compatible calendars, manage recurring events, and respond to invitations — all from within Wino.",
             "imageUrl": "ms-appx:///Assets/UpdateNotes/Images/Calendar.svg",
             "imageWidth": 128,
             "imageHeight": 128
         },
         {
-            "title": "# S/MIME Signing & Encryption",
+            "title": "S/MIME Signing & Encryption",
             "description": "Wino now supports signing and encrypting your emails with personal certificates. Keep your communications secure and verifiable.",
             "imageUrl": "ms-appx:///Assets/UpdateNotes/Images/Security.svg",
             "imageWidth": 128,
             "imageHeight": 128
         },
         {
-            "title": "# Threaded Mail View",
+            "title": "Threaded Mail View",
             "description": "Emails are now grouped by conversation, making it easier to follow long discussions without losing context.",
             "imageUrl": "ms-appx:///Assets/UpdateNotes/Images/Thread.svg",
             "imageWidth": 128,
             "imageHeight": 128
         },
         {
-            "title": "# Smarter Notifications",
+            "title": "Smarter Notifications",
             "description": "Act on your emails directly from toast notifications — mark as read, delete, or archive without opening the app.",
             "imageUrl": "ms-appx:///Assets/UpdateNotes/Images/Notification.svg",
             "imageWidth": 128,
             "imageHeight": 128
         },
         {
-            "title": "# And much more...",
+            "title": "And much more...",
             "description": "Folder management, swipe actions, keyboard shortcuts, a custom print dialog, and significant performance improvements are all included in this release.\n\nThank you for using Wino Mail!",
             "imageUrl": "ms-appx:///Assets/UpdateNotes/Images/More.svg",
             "imageWidth": 128,

Wino.Mail.WinUI/BasePage.cs

@@ -13,6 +13,8 @@ namespace Wino.Mail.WinUI;
 
 public partial class BasePage : Page, IRecipient<LanguageChanged>
 {
+    private bool _isPreparedForClose;
+
     public void Receive(LanguageChanged message)
     {
         OnLanguageChanged();
@@ -31,6 +33,24 @@ public partial class BasePage : Page, IRecipient<LanguageChanged>
     protected virtual void UnregisterRecipients() { }
 
     public virtual CoreBaseViewModel? AssociatedViewModel => null;
+
+    public virtual void PrepareForClose()
+    {
+        if (_isPreparedForClose)
+            return;
+
+        _isPreparedForClose = true;
+
+        WeakReferenceMessenger.Default.Unregister<LanguageChanged>(this);
+        UnregisterRecipients();
+    }
+
+    protected void ResetPreparedForCloseState()
+    {
+        _isPreparedForClose = false;
+    }
+
+    protected bool IsPreparedForClose => _isPreparedForClose;
 }
 
 public abstract class BasePage<T> : BasePage where T : CoreBaseViewModel
@@ -63,6 +83,7 @@ public abstract class BasePage<T> : BasePage where T : CoreBaseViewModel
         var mode = GetNavigationMode(e.NavigationMode);
         var parameter = e.Parameter;
 
+        ResetPreparedForCloseState();
         WeakReferenceMessenger.Default.Register<LanguageChanged>(this);
         RegisterRecipients();
 
@@ -76,14 +97,25 @@ public abstract class BasePage<T> : BasePage where T : CoreBaseViewModel
         var mode = GetNavigationMode(e.NavigationMode);
         var parameter = e.Parameter;
 
-        WeakReferenceMessenger.Default.Unregister<LanguageChanged>(this);
-        UnregisterRecipients();
-
-        ViewModel.OnNavigatedFrom(mode, parameter);
+        PrepareForClose(mode, parameter);
 
         GC.Collect();
     }
 
+    public override void PrepareForClose()
+    {
+        PrepareForClose(WinoNavigationMode.New, null);
+    }
+
+    private void PrepareForClose(WinoNavigationMode mode, object? parameter)
+    {
+        if (IsPreparedForClose)
+            return;
+
+        base.PrepareForClose();
+        ViewModel.OnNavigatedFrom(mode, parameter!);
+    }
+
     private WinoNavigationMode GetNavigationMode(NavigationMode mode)
     {
         return (WinoNavigationMode)mode;

Wino.Mail.WinUI/Helpers/WindowCleanupHelper.cs

@@ -0,0 +1,72 @@
+using System;
+using System.Collections.Generic;
+using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Controls;
+using Microsoft.UI.Xaml.Media;
+
+namespace Wino.Mail.WinUI.Helpers;
+
+internal static class WindowCleanupHelper
+{
+    public static void CleanupFrame(Frame? frame)
+    {
+        if (frame == null)
+            return;
+
+        CleanupObject(frame.Content);
+        frame.BackStack.Clear();
+        frame.ForwardStack.Clear();
+        frame.Content = null;
+    }
+
+    public static void CleanupObject(object? instance)
+    {
+        if (instance == null)
+            return;
+
+        var visited = new HashSet<object>(ReferenceEqualityComparer.Instance);
+        CleanupObject(instance, visited);
+    }
+
+    private static void CleanupObject(object? instance, HashSet<object> visited)
+    {
+        if (instance == null || !visited.Add(instance))
+            return;
+
+        switch (instance)
+        {
+            case Views.WinoAppShell shell:
+                shell.PrepareForWindowClose();
+                break;
+            case Frame frame:
+                CleanupFrame(frame);
+                break;
+            case BasePage page:
+                page.PrepareForClose();
+                break;
+        }
+
+        if (instance is DependencyObject dependencyObject)
+        {
+            var childCount = VisualTreeHelper.GetChildrenCount(dependencyObject);
+            for (int i = 0; i < childCount; i++)
+            {
+                CleanupObject(VisualTreeHelper.GetChild(dependencyObject, i), visited);
+            }
+        }
+
+        if (instance is IDisposable disposable)
+        {
+            disposable.Dispose();
+        }
+    }
+
+    private sealed class ReferenceEqualityComparer : IEqualityComparer<object>
+    {
+        public static ReferenceEqualityComparer Instance { get; } = new();
+
+        public new bool Equals(object? x, object? y) => ReferenceEquals(x, y);
+
+        public int GetHashCode(object obj) => System.Runtime.CompilerServices.RuntimeHelpers.GetHashCode(obj);
+    }
+}

Wino.Mail.WinUI/Services/PreferencesService.cs

@@ -221,12 +221,6 @@ public class PreferencesService(IConfigurationService configurationService) : Ob
         set => SetPropertyAndSave(nameof(IsLoggingEnabled), value);
     }
 
-    public bool IsMailkitProtocolLoggerEnabled
-    {
-        get => _configurationService.Get(nameof(IsMailkitProtocolLoggerEnabled), false);
-        set => SetPropertyAndSave(nameof(IsMailkitProtocolLoggerEnabled), value);
-    }
-
     public bool IsGravatarEnabled
     {
         get => _configurationService.Get(nameof(IsGravatarEnabled), true);

Wino.Mail.WinUI/ShellWindow.xaml.cs

@@ -16,6 +16,7 @@ using Wino.Core.Domain.Models.Synchronization;
 using Wino.Extensions;
 using Wino.Mail.WinUI.Activation;
 using Wino.Mail.WinUI.Extensions;
+using Wino.Mail.WinUI.Helpers;
 using Wino.Mail.WinUI.Interfaces;
 using Wino.Mail.WinUI.Models;
 using Wino.Mail.WinUI.Views;
@@ -46,6 +47,7 @@ public sealed partial class ShellWindow : WindowEx, IWinoShellWindow,
     private ITitleBarSearchHost? _activeTitleBarSearchHost;
     private bool _isBackButtonVisibilityReady;
     private bool _isSynchronizingTitleBarSearch;
+    private bool _isPreparedForClose;
 
     public ShellWindow()
     {
@@ -365,11 +367,18 @@ public sealed partial class ShellWindow : WindowEx, IWinoShellWindow,
 
     public void PrepareForClose()
     {
+        if (_isPreparedForClose)
+            return;
+
+        _isPreparedForClose = true;
+
         if (MainShellFrame.Content is WinoAppShell shellPage)
         {
             shellPage.PrepareForWindowClose();
         }
 
+        WindowCleanupHelper.CleanupFrame(MainShellFrame);
+
         _allowClose = true;
     }
 
@@ -384,6 +393,7 @@ public sealed partial class ShellWindow : WindowEx, IWinoShellWindow,
             shellPage.PrepareForWindowClose();
         }
 
+        WindowCleanupHelper.CleanupFrame(MainShellFrame);
         UnregisterRecipients();
     }
 

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

@@ -25,19 +25,21 @@ public sealed partial class WelcomeHostPage : WelcomeHostPageAbstract,
     protected override void OnNavigatedTo(NavigationEventArgs e)
     {
         base.OnNavigatedTo(e);
-
-        WeakReferenceMessenger.Default.Register<BreadcrumbNavigationRequested>(this);
-        WeakReferenceMessenger.Default.Register<BackBreadcrumNavigationRequested>(this);
-
         ResetWizard();
     }
 
-    protected override void OnNavigatingFrom(NavigatingCancelEventArgs e)
+    protected override void RegisterRecipients()
     {
+        base.RegisterRecipients();
+        WeakReferenceMessenger.Default.Register<BreadcrumbNavigationRequested>(this);
+        WeakReferenceMessenger.Default.Register<BackBreadcrumNavigationRequested>(this);
+    }
+
+    protected override void UnregisterRecipients()
+    {
+        base.UnregisterRecipients();
         WeakReferenceMessenger.Default.Unregister<BreadcrumbNavigationRequested>(this);
         WeakReferenceMessenger.Default.Unregister<BackBreadcrumNavigationRequested>(this);
-
-        base.OnNavigatingFrom(e);
     }
 
     public void Receive(BreadcrumbNavigationRequested message)

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

@@ -28,6 +28,7 @@ using Wino.Mail.ViewModels;
 using Wino.Mail.ViewModels.Data;
 using Wino.Mail.WinUI.ViewModels;
 using Wino.Mail.WinUI.Controls;
+using Wino.Mail.WinUI.Helpers;
 using Wino.MenuFlyouts;
 using Wino.MenuFlyouts.Context;
 using Wino.Messaging.Client.Accounts;
@@ -127,6 +128,7 @@ public sealed partial class WinoAppShell : Views.Abstract.WinoAppShellAbstract,
 
         navigationView.MenuItemsSource = null;
         CalendarHostListView.ItemsSource = null;
+        WindowCleanupHelper.CleanupFrame(InnerShellFrame);
     }
 
     private void OnLoaded(object sender, RoutedEventArgs e)

Wino.Mail.WinUI/WelcomeWindow.xaml.cs

@@ -3,6 +3,7 @@ using Microsoft.UI.Windowing;
 using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Controls;
 using Wino.Core.Domain.Interfaces;
+using Wino.Mail.WinUI.Helpers;
 using Wino.Mail.WinUI.Interfaces;
 using WinUIEx;
 
@@ -11,6 +12,7 @@ namespace Wino.Mail.WinUI;
 public sealed partial class WelcomeWindow : WindowEx
 {
     private bool _allowClose;
+    private bool _isPreparedForClose;
 
     public Frame GetRootFrame() => RootFrame;
 
@@ -25,6 +27,7 @@ public sealed partial class WelcomeWindow : WindowEx
 
         ConfigureWindowChrome();
         AppWindow.Closing += OnAppWindowClosing;
+        Closed += OnWindowClosed;
     }
 
     private void ConfigureWindowChrome()
@@ -55,4 +58,20 @@ public sealed partial class WelcomeWindow : WindowEx
     {
         _allowClose = true;
     }
+
+    public void PrepareForClose()
+    {
+        if (_isPreparedForClose)
+            return;
+
+        _isPreparedForClose = true;
+        WindowCleanupHelper.CleanupFrame(RootFrame);
+    }
+
+    private void OnWindowClosed(object sender, WindowEventArgs e)
+    {
+        Closed -= OnWindowClosed;
+        AppWindow.Closing -= OnAppWindowClosing;
+        PrepareForClose();
+    }
 }