Improved shell experience.

Wino.Calendar.ViewModels/CalendarAppShellViewModel.cs

@@ -23,7 +23,6 @@ using Wino.Core.Domain.Models.Navigation;
 using Wino.Core.Domain.Models.Synchronization;
 using Wino.Core.ViewModels;
 using Wino.Messaging.Client.Calendar;
-using Wino.Messaging.Client.Navigation;
 using Wino.Messaging.Server;
 using Wino.Messaging.UI;
 
@@ -33,7 +32,6 @@ public partial class CalendarAppShellViewModel : CalendarBaseViewModel,
     ICalendarShellClient,
     IRecipient<VisibleDateRangeChangedMessage>,
     IRecipient<CalendarEnableStatusChangedMessage>,
-    IRecipient<NavigateManageAccountsRequested>,
     IRecipient<CalendarDisplayTypeChangedMessage>,
     IRecipient<AccountRemovedMessage>
 {
@@ -94,6 +92,7 @@ public partial class CalendarAppShellViewModel : CalendarBaseViewModel,
 
     // For updating account calendars asynchronously.
     private SemaphoreSlim _accountCalendarUpdateSemaphoreSlim = new(1);
+    private bool _runtimeSubscriptionsAttached;
 
     public CalendarAppShellViewModel(IPreferencesService preferencesService,
                              IStatePersistanceService statePersistanceService,
@@ -101,25 +100,24 @@ public partial class CalendarAppShellViewModel : CalendarBaseViewModel,
                              ICalendarService calendarService,
                              IAccountCalendarStateService accountCalendarStateService,
                              INavigationService navigationService,
+                             CalendarPageViewModel calendarPageViewModel,
                              IMailDialogService dialogService,
                              IUpdateManager updateManager,
                              IStoreUpdateService storeUpdateService)
     {
         _accountService = accountService;
         _calendarService = calendarService;
+        _calendarPageViewModel = calendarPageViewModel;
         _dialogService = dialogService;
         _updateManager = updateManager;
         _storeUpdateService = storeUpdateService;
 
         AccountCalendarStateService = accountCalendarStateService;
-        AccountCalendarStateService.AccountCalendarSelectionStateChanged += UpdateAccountCalendarRequested;
-        AccountCalendarStateService.CollectiveAccountGroupSelectionStateChanged += AccountCalendarStateCollectivelyChanged;
 
         NavigationService = navigationService;
         PreferencesService = preferencesService;
 
         StatePersistenceService = statePersistanceService;
-        StatePersistenceService.StatePropertyChanged += PrefefencesChanged;
     }
 
     protected override void OnDispatcherAssigned()
@@ -157,9 +155,9 @@ public partial class CalendarAppShellViewModel : CalendarBaseViewModel,
     public override async void OnNavigatedTo(NavigationMode mode, object parameters)
     {
         base.OnNavigatedTo(mode, parameters);
+        AttachRuntimeSubscriptions();
 
         var activationContext = parameters as ShellModeActivationContext;
-        var isModeResetActivation = activationContext != null;
         var shouldRunStartupFlows = activationContext?.IsInitialActivation ?? true;
 
         PreferencesService.PreferenceChanged -= PreferencesServiceChanged;
@@ -167,18 +165,6 @@ public partial class CalendarAppShellViewModel : CalendarBaseViewModel,
 
         await RefreshFooterItemsAsync(mode == NavigationMode.New);
 
-        // Preserve the existing calendar shell frame state when the user switches
-        // between Mail and Calendar modes. Back/forward restoration should not
-        // force a new CalendarPage navigation, otherwise pages like
-        // CalendarEventComposePage get dropped from the inner frame stack.
-        if (mode != NavigationMode.New && !isModeResetActivation)
-        {
-            UpdateDateNavigationHeaderItems();
-            await InitializeAccountCalendarsAsync();
-            ValidateConfiguredNewEventCalendar();
-            return;
-        }
-
         UpdateDateNavigationHeaderItems();
 
         await InitializeAccountCalendarsAsync();
@@ -196,7 +182,38 @@ public partial class CalendarAppShellViewModel : CalendarBaseViewModel,
     {
         base.OnNavigatedFrom(mode, parameters);
 
+        DetachRuntimeSubscriptions();
         PreferencesService.PreferenceChanged -= PreferencesServiceChanged;
+        _ = ExecuteUIThread(() =>
+        {
+            DateNavigationHeaderItems.Clear();
+            AccountCalendarStateService.ClearGroupedAccountCalendars();
+            HighlightedDateRange = null;
+            SelectedDateNavigationHeaderIndex = -1;
+        });
+        _calendarPageViewModel.CleanupForShellDeactivation();
+    }
+
+    private void AttachRuntimeSubscriptions()
+    {
+        if (_runtimeSubscriptionsAttached)
+            return;
+
+        AccountCalendarStateService.AccountCalendarSelectionStateChanged += UpdateAccountCalendarRequested;
+        AccountCalendarStateService.CollectiveAccountGroupSelectionStateChanged += AccountCalendarStateCollectivelyChanged;
+        StatePersistenceService.StatePropertyChanged += PrefefencesChanged;
+        _runtimeSubscriptionsAttached = true;
+    }
+
+    private void DetachRuntimeSubscriptions()
+    {
+        if (!_runtimeSubscriptionsAttached)
+            return;
+
+        AccountCalendarStateService.AccountCalendarSelectionStateChanged -= UpdateAccountCalendarRequested;
+        AccountCalendarStateService.CollectiveAccountGroupSelectionStateChanged -= AccountCalendarStateCollectivelyChanged;
+        StatePersistenceService.StatePropertyChanged -= PrefefencesChanged;
+        _runtimeSubscriptionsAttached = false;
     }
 
     private async Task ShowWhatIsNewIfNeededAsync()
@@ -346,6 +363,7 @@ public partial class CalendarAppShellViewModel : CalendarBaseViewModel,
     private DateTime? _navigationDate;
     private readonly IAccountService _accountService;
     private readonly ICalendarService _calendarService;
+    private readonly CalendarPageViewModel _calendarPageViewModel;
     private readonly IMailDialogService _dialogService;
     private readonly IUpdateManager _updateManager;
     private readonly IStoreUpdateService _storeUpdateService;
@@ -455,7 +473,6 @@ public partial class CalendarAppShellViewModel : CalendarBaseViewModel,
 
         Messenger.Register<VisibleDateRangeChangedMessage>(this);
         Messenger.Register<CalendarEnableStatusChangedMessage>(this);
-        Messenger.Register<NavigateManageAccountsRequested>(this);
         Messenger.Register<CalendarDisplayTypeChangedMessage>(this);
         Messenger.Register<AccountRemovedMessage>(this);
     }
@@ -466,7 +483,6 @@ public partial class CalendarAppShellViewModel : CalendarBaseViewModel,
 
         Messenger.Unregister<VisibleDateRangeChangedMessage>(this);
         Messenger.Unregister<CalendarEnableStatusChangedMessage>(this);
-        Messenger.Unregister<NavigateManageAccountsRequested>(this);
         Messenger.Unregister<CalendarDisplayTypeChangedMessage>(this);
         Messenger.Unregister<AccountRemovedMessage>(this);
     }
@@ -558,8 +574,6 @@ public partial class CalendarAppShellViewModel : CalendarBaseViewModel,
     public async void Receive(CalendarEnableStatusChangedMessage message)
         => await ExecuteUIThread(() => IsCalendarEnabled = message.IsEnabled);
 
-    public void Receive(NavigateManageAccountsRequested message) => NavigationService.Navigate(WinoPage.ManageAccountsPage);
-
     public void Receive(CalendarDisplayTypeChangedMessage message)
     {
         OnPropertyChanged(nameof(IsVerticalCalendar));

Wino.Calendar.ViewModels/CalendarPageViewModel.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
+using System.Runtime.InteropServices;
 using System.Threading;
 using System.Threading.Tasks;
 using CommunityToolkit.Diagnostics;
@@ -20,9 +21,9 @@ using Wino.Core.Domain.Entities.Calendar;
 using Wino.Core.Domain.Enums;
 using Wino.Core.Domain.Extensions;
 using Wino.Core.Domain.Interfaces;
+using Wino.Core.Domain.Models;
 using Wino.Core.Domain.Models.Calendar;
 using Wino.Core.Domain.Models.Calendar.CalendarTypeStrategies;
-using Wino.Core.Domain.Models;
 using Wino.Core.Domain.Models.Navigation;
 using Wino.Core.ViewModels;
 using Wino.Messaging.Client.Calendar;
@@ -37,7 +38,8 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
     IRecipient<CalendarItemTappedMessage>,
     IRecipient<CalendarItemDoubleTappedMessage>,
     IRecipient<CalendarItemRightTappedMessage>,
-    IRecipient<AccountRemovedMessage>
+    IRecipient<AccountRemovedMessage>,
+    IDisposable
 {
     #region Quick Event Creation
 
@@ -145,6 +147,9 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
 
     private SemaphoreSlim _calendarLoadingSemaphore = new(1);
     private bool isLoadMoreBlocked = false;
+    private bool _subscriptionsAttached;
+    private CancellationTokenSource _pageLifetimeCts = new();
+    private long _pageLifetimeVersion;
 
     [ObservableProperty]
     private CalendarSettings _currentSettings;
@@ -173,11 +178,6 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
         _winoRequestDelegator = winoRequestDelegator;
         _dialogService = dialogService;
 
-        AccountCalendarStateService.AccountCalendarSelectionStateChanged += UpdateAccountCalendarRequested;
-        AccountCalendarStateService.CollectiveAccountGroupSelectionStateChanged += AccountCalendarStateCollectivelyChanged;
-
-        // We don't register on navigation here. This page is cached.
-        RegisterRecipients();
     }
 
     public override async Task KeyboardShortcutHook(KeyboardShortcutTriggerDetails args)
@@ -228,15 +228,35 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
         Messenger.Register<AccountRemovedMessage>(this);
     }
 
+    protected override void UnregisterRecipients()
+    {
+        base.UnregisterRecipients();
+
+        Messenger.Unregister<LoadCalendarMessage>(this);
+        Messenger.Unregister<CalendarSettingsUpdatedMessage>(this);
+        Messenger.Unregister<CalendarItemTappedMessage>(this);
+        Messenger.Unregister<CalendarItemDoubleTappedMessage>(this);
+        Messenger.Unregister<CalendarItemRightTappedMessage>(this);
+        Messenger.Unregister<AccountRemovedMessage>(this);
+    }
+
     private void AccountCalendarStateCollectivelyChanged(object sender, GroupedAccountCalendarViewModel e)
-        => FilterActiveCalendars(DayRanges);
+        => _ = FilterActiveCalendarsAsync(DayRanges);
 
     private void UpdateAccountCalendarRequested(object sender, AccountCalendarViewModel e)
-        => FilterActiveCalendars(DayRanges);
+        => _ = FilterActiveCalendarsAsync(DayRanges);
 
-    private async void FilterActiveCalendars(IEnumerable<DayRangeRenderModel> dayRangeRenderModels)
+    private async Task FilterActiveCalendarsAsync(IEnumerable<DayRangeRenderModel> dayRangeRenderModels)
     {
-        await ExecuteUIThread(() =>
+        await FilterActiveCalendarsAsync(dayRangeRenderModels, CurrentPageLifetimeVersion).ConfigureAwait(false);
+    }
+
+    private async Task FilterActiveCalendarsAsync(IEnumerable<DayRangeRenderModel> dayRangeRenderModels, long lifetimeVersion)
+    {
+        if (dayRangeRenderModels == null || !IsPageActive(lifetimeVersion))
+            return;
+
+        await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () =>
         {
             var days = dayRangeRenderModels.SelectMany(a => a.CalendarDays);
 
@@ -269,10 +289,15 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
 
     public override void OnNavigatedTo(NavigationMode mode, object parameters)
     {
+        ResetPageLifetime();
+        base.OnNavigatedTo(mode, parameters);
+        AttachSubscriptions();
         RefreshSettings();
+        IsCalendarEnabled = true;
 
-        if (mode == NavigationMode.Back)
+        if (mode == NavigationMode.Back && DayRanges.Count > 0)
         {
+            RestoreVisibleState();
             _ = RefreshVisibleRangesAsync();
             return;
         }
@@ -283,8 +308,197 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
 
     public override void OnNavigatedFrom(NavigationMode mode, object parameters)
     {
-        // CalendarPage is cached and should continue processing calendar item messages
+        base.OnNavigatedFrom(mode, parameters);
-        // while details/compose pages are active on top of it.
+
+        if (StatePersistanceService.ApplicationMode == WinoApplicationMode.Calendar)
+        {
+            CancelPendingOperations();
+            DetachSubscriptions();
+            return;
+        }
+
+        CleanupForShellDeactivation();
+    }
+
+    private void AttachSubscriptions()
+    {
+        if (_subscriptionsAttached)
+            return;
+
+        AccountCalendarStateService.AccountCalendarSelectionStateChanged += UpdateAccountCalendarRequested;
+        AccountCalendarStateService.CollectiveAccountGroupSelectionStateChanged += AccountCalendarStateCollectivelyChanged;
+        _subscriptionsAttached = true;
+    }
+
+    private void DetachSubscriptions()
+    {
+        if (!_subscriptionsAttached)
+            return;
+
+        AccountCalendarStateService.AccountCalendarSelectionStateChanged -= UpdateAccountCalendarRequested;
+        AccountCalendarStateService.CollectiveAccountGroupSelectionStateChanged -= AccountCalendarStateCollectivelyChanged;
+        _subscriptionsAttached = false;
+    }
+
+    private void ReleasePageState()
+    {
+        DetachSubscriptions();
+
+        DisplayDetailsCalendarItemViewModel = null;
+        SelectedQuickEventAccountCalendar = null;
+        SelectedQuickEventDate = null;
+        SelectedDayRange = null;
+        SelectedDateRangeIndex = 0;
+        IsQuickEventDialogOpen = false;
+        DayRanges = [];
+        HourSelectionStrings = [];
+    }
+
+    public void Dispose()
+    {
+        CleanupForShellDeactivation();
+    }
+
+    public void CleanupForShellDeactivation()
+    {
+        CancelPendingOperations();
+        ReleasePageState();
+        GC.SuppressFinalize(this);
+    }
+
+    public bool RestoreVisibleState()
+    {
+        IsCalendarEnabled = true;
+
+        if (DayRanges.Count == 0)
+        {
+            SelectedDayRange = null;
+            SelectedDateRangeIndex = -1;
+            return false;
+        }
+
+        var targetIndex = SelectedDateRangeIndex;
+
+        if (SelectedDayRange != null)
+        {
+            var existingSelectedRangeIndex = DayRanges.IndexOf(SelectedDayRange);
+            if (existingSelectedRangeIndex >= 0)
+            {
+                targetIndex = existingSelectedRangeIndex;
+            }
+        }
+
+        if (targetIndex < 0 || targetIndex >= DayRanges.Count)
+        {
+            targetIndex = 0;
+        }
+
+        SelectedDateRangeIndex = targetIndex;
+        SelectedDayRange = DayRanges[targetIndex];
+
+        return true;
+    }
+
+    public DateTime GetRestoreDate()
+    {
+        if (SelectedDayRange != null)
+        {
+            return SelectedDayRange.CalendarRenderOptions.DateRange.StartDate;
+        }
+
+        if (DayRanges.Count == 0)
+        {
+            return DateTime.Now.Date;
+        }
+
+        var targetIndex = SelectedDateRangeIndex;
+        if (targetIndex < 0 || targetIndex >= DayRanges.Count)
+        {
+            targetIndex = 0;
+        }
+
+        return DayRanges[targetIndex].CalendarRenderOptions.DateRange.StartDate;
+    }
+
+    private long CurrentPageLifetimeVersion => Interlocked.Read(ref _pageLifetimeVersion);
+
+    private bool IsPageActive(long lifetimeVersion)
+        => lifetimeVersion == CurrentPageLifetimeVersion && !_pageLifetimeCts.IsCancellationRequested;
+
+    private bool IsCurrentPageActive => !_pageLifetimeCts.IsCancellationRequested;
+
+    private void ResetPageLifetime()
+    {
+        CancelPendingOperations();
+        _pageLifetimeCts = new CancellationTokenSource();
+        Interlocked.Increment(ref _pageLifetimeVersion);
+    }
+
+    private void CancelPendingOperations()
+    {
+        if (!_pageLifetimeCts.IsCancellationRequested)
+        {
+            _pageLifetimeCts.Cancel();
+        }
+    }
+
+    private async Task<bool> WaitForCalendarLoadingLockAsync(long lifetimeVersion)
+    {
+        if (!IsPageActive(lifetimeVersion))
+            return false;
+
+        var cancellationToken = _pageLifetimeCts.Token;
+
+        try
+        {
+            await _calendarLoadingSemaphore.WaitAsync(cancellationToken).ConfigureAwait(false);
+            return IsPageActive(lifetimeVersion);
+        }
+        catch (OperationCanceledException)
+        {
+            return false;
+        }
+        catch (ObjectDisposedException)
+        {
+            return false;
+        }
+    }
+
+    private void ReleaseCalendarLoadingLock()
+    {
+        try
+        {
+            _calendarLoadingSemaphore.Release();
+        }
+        catch (ObjectDisposedException)
+        {
+        }
+        catch (SemaphoreFullException)
+        {
+        }
+    }
+
+    private async Task ExecuteUIThreadIfActiveAsync(long lifetimeVersion, Action action)
+    {
+        if (action == null || !IsPageActive(lifetimeVersion))
+            return;
+
+        try
+        {
+            await ExecuteUIThread(() =>
+            {
+                if (IsPageActive(lifetimeVersion))
+                {
+                    action();
+                }
+            }).ConfigureAwait(false);
+        }
+        catch (COMException) when (!IsPageActive(lifetimeVersion))
+        {
+        }
+        catch (ObjectDisposedException) when (!IsPageActive(lifetimeVersion))
+        {
+        }
     }
 
     [RelayCommand]
@@ -492,21 +706,27 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
 
     public async void Receive(LoadCalendarMessage message)
     {
-        await _calendarLoadingSemaphore.WaitAsync();
+        var lifetimeVersion = CurrentPageLifetimeVersion;
+        var hasLoadingLock = await WaitForCalendarLoadingLockAsync(lifetimeVersion).ConfigureAwait(false);
+
+        if (!hasLoadingLock)
+            return;
 
         try
         {
-            await ExecuteUIThread(() => IsCalendarEnabled = false);
+            await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () => IsCalendarEnabled = false).ConfigureAwait(false);
 
-            if (ShouldResetDayRanges(message))
+            if (!IsPageActive(lifetimeVersion))
-            {
+                return;
-                Debug.WriteLine("Will reset day ranges.");
+
-                await ClearDayRangeModelsAsync();
+            if (!ShouldResetDayRanges(message) && ShouldScrollToItem(message))
-            }
-            else if (ShouldScrollToItem(message))
             {
                 // Scroll to the selected date.
-                Messenger.Send(new ScrollToDateMessage(message.DisplayDate));
+                if (IsPageActive(lifetimeVersion))
+                {
+                    Messenger.Send(new ScrollToDateMessage(message.DisplayDate));
+                }
+
                 Debug.WriteLine("Scrolling to selected date.");
                 return;
             }
@@ -516,10 +736,23 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
             // This will replace the whole collection because the user initiated a new render.
             await RenderDatesAsync(message.CalendarInitInitiative,
                                    message.DisplayDate,
-                                   CalendarLoadDirection.Replace);
+                                   CalendarLoadDirection.Replace,
+                                   lifetimeVersion).ConfigureAwait(false);
 
             // Scroll to the current hour.
-            Messenger.Send(new ScrollToHourMessage(TimeSpan.FromHours(DateTime.Now.Hour)));
+            if (IsPageActive(lifetimeVersion))
+            {
+                Messenger.Send(new ScrollToHourMessage(TimeSpan.FromHours(DateTime.Now.Hour)));
+            }
+        }
+        catch (OperationCanceledException)
+        {
+        }
+        catch (COMException) when (!IsPageActive(lifetimeVersion))
+        {
+        }
+        catch (ObjectDisposedException) when (!IsPageActive(lifetimeVersion))
+        {
         }
         catch (Exception ex)
         {
@@ -528,55 +761,88 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
         }
         finally
         {
-            _calendarLoadingSemaphore.Release();
+            ReleaseCalendarLoadingLock();
 
-            await ExecuteUIThread(() => IsCalendarEnabled = true);
+            await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () => IsCalendarEnabled = true).ConfigureAwait(false);
         }
     }
 
 
-    private async Task AddDayRangeModelAsync(DayRangeRenderModel dayRangeRenderModel)
+    private async Task AddDayRangeModelAsync(DayRangeRenderModel dayRangeRenderModel, long lifetimeVersion)
     {
         if (dayRangeRenderModel == null) return;
 
-        await ExecuteUIThread(() =>
+        await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () =>
         {
             DayRanges.Add(dayRangeRenderModel);
         });
     }
 
-    private async Task InsertDayRangeModelAsync(DayRangeRenderModel dayRangeRenderModel, int index)
+    private async Task InsertDayRangeModelAsync(DayRangeRenderModel dayRangeRenderModel, int index, long lifetimeVersion)
     {
         if (dayRangeRenderModel == null) return;
 
-        await ExecuteUIThread(() =>
+        await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () =>
         {
             DayRanges.Insert(index, dayRangeRenderModel);
         });
     }
 
-    private async Task RemoveDayRangeModelAsync(DayRangeRenderModel dayRangeRenderModel)
+    private async Task RemoveDayRangeModelAsync(DayRangeRenderModel dayRangeRenderModel, long lifetimeVersion)
     {
         if (dayRangeRenderModel == null) return;
 
-        await ExecuteUIThread(() =>
+        await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () =>
         {
             DayRanges.Remove(dayRangeRenderModel);
         });
     }
 
-    private async Task ClearDayRangeModelsAsync()
+    private async Task ClearDayRangeModelsAsync(long lifetimeVersion)
     {
-        await ExecuteUIThread(() =>
+        await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () =>
         {
             DayRanges.Clear();
         });
     }
 
+    private async Task ReplaceDayRangeModelsAsync(IEnumerable<DayRangeRenderModel> dayRangeRenderModels, DateTime displayDate, long lifetimeVersion)
+    {
+        var renderModels = dayRangeRenderModels?.ToList() ?? [];
+
+        await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () =>
+        {
+            DayRanges.ReplaceRange(renderModels);
+
+            if (renderModels.Count == 0)
+            {
+                SelectedDayRange = null;
+                SelectedDateRangeIndex = -1;
+                return;
+            }
+
+            var selectedIndex = renderModels.FindIndex(model =>
+                displayDate >= model.CalendarRenderOptions.DateRange.StartDate &&
+                displayDate <= model.CalendarRenderOptions.DateRange.EndDate);
+
+            if (selectedIndex < 0)
+            {
+                selectedIndex = 0;
+            }
+
+            SelectedDateRangeIndex = selectedIndex;
+            SelectedDayRange = renderModels[selectedIndex];
+        });
+    }
+
     private async Task RenderDatesAsync(CalendarInitInitiative calendarInitInitiative,
                                         DateTime? loadingDisplayDate = null,
-                                        CalendarLoadDirection calendarLoadDirection = CalendarLoadDirection.Replace)
+                                        CalendarLoadDirection calendarLoadDirection = CalendarLoadDirection.Replace,
+                                        long lifetimeVersion = 0)
     {
+        if (!IsPageActive(lifetimeVersion))
+            return;
+
         isLoadMoreBlocked = calendarLoadDirection == CalendarLoadDirection.Replace;
 
         // This is the part we arrange the flip view calendar logic.
@@ -643,11 +909,17 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
         // Dates are loaded. Now load the events for them.
         foreach (var renderModel in renderModels)
         {
-            await InitializeCalendarEventsForDayRangeAsync(renderModel).ConfigureAwait(false);
+            await InitializeCalendarEventsForDayRangeAsync(renderModel, lifetimeVersion).ConfigureAwait(false);
+
+            if (!IsPageActive(lifetimeVersion))
+                return;
         }
 
         // Filter by active calendars. This is a quick operation, and things are not on the UI yet.
-        FilterActiveCalendars(renderModels);
+        await FilterActiveCalendarsAsync(renderModels, lifetimeVersion).ConfigureAwait(false);
+
+        if (!IsPageActive(lifetimeVersion))
+            return;
 
         CalendarLoadDirection animationDirection = calendarLoadDirection;
 
@@ -655,29 +927,26 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
 
         if (calendarLoadDirection == CalendarLoadDirection.Replace)
         {
-            // New date ranges are being replaced.
-            // We must preserve existing selection if any, add the items before/after the current one, remove the current one.
-            // This will make sure the new dates are animated in the correct direction.
-
             isLoadMoreBlocked = true;
+            await ReplaceDayRangeModelsAsync(renderModels, displayDate, lifetimeVersion).ConfigureAwait(false);
+            isLoadMoreBlocked = false;
 
-            // Remove all other dates except this one.
+            if (calendarInitInitiative == CalendarInitInitiative.User)
-            var rangesToRemove = DayRanges.Where(a => a != SelectedDayRange).ToList();
-
-            foreach (var range in rangesToRemove)
             {
-                await RemoveDayRangeModelAsync(range);
+                _currentDisplayType = StatePersistanceService.CalendarDisplayType;
+                _displayDayCount = StatePersistanceService.DayDisplayCount;
+
+                Messenger.Send(new ScrollToDateMessage(displayDate));
             }
 
-            animationDirection = displayDate <= SelectedDayRange?.CalendarRenderOptions.DateRange.StartDate ?
+            return;
-                CalendarLoadDirection.Previous : CalendarLoadDirection.Next;
         }
 
         if (animationDirection == CalendarLoadDirection.Next)
         {
             foreach (var item in renderModels)
             {
-                await AddDayRangeModelAsync(item);
+                await AddDayRangeModelAsync(item, lifetimeVersion);
             }
         }
         else if (animationDirection == CalendarLoadDirection.Previous)
@@ -690,7 +959,7 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
             // Insert each render model in reverse order.
             for (int i = renderModels.Count - 1; i >= 0; i--)
             {
-                await InsertDayRangeModelAsync(renderModels[i], 0);
+                await InsertDayRangeModelAsync(renderModels[i], 0, lifetimeVersion);
             }
         }
 
@@ -723,12 +992,15 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
         }
     }
 
-    private async Task InitializeCalendarEventsForDayRangeAsync(DayRangeRenderModel dayRangeRenderModel)
+    private async Task InitializeCalendarEventsForDayRangeAsync(DayRangeRenderModel dayRangeRenderModel, long lifetimeVersion)
     {
+        if (!IsPageActive(lifetimeVersion))
+            return;
+
         // Clear all events first for all days.
         foreach (var day in dayRangeRenderModel.CalendarDays)
         {
-            await ExecuteUIThread(() =>
+            await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () =>
             {
                 day.EventsCollection.Clear();
             });
@@ -739,6 +1011,9 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
 
         foreach (var calendarViewModel in AccountCalendarStateService.AllCalendars)
         {
+            if (!IsPageActive(lifetimeVersion))
+                return;
+
             // Check all the events for the given date range and calendar.
             // Then find the day representation for all the events returned, and add to the collection.
 
@@ -746,13 +1021,16 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
 
             foreach (var @event in events)
             {
+                if (!IsPageActive(lifetimeVersion))
+                    return;
+
                 // Find the days that the event falls into.
                 var allDaysForEvent = dayRangeRenderModel.CalendarDays.Where(a => a.Period.OverlapsWith(@event.Period));
 
                 foreach (var calendarDay in allDaysForEvent)
                 {
                     var calendarItemViewModel = new CalendarItemViewModel(@event);
-                    await ExecuteUIThread(() =>
+                    await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () =>
                     {
                         calendarDay.EventsCollection.AddCalendarItem(calendarItemViewModel);
                     });
@@ -763,21 +1041,33 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
 
     private async Task RefreshVisibleRangesAsync()
     {
+        var lifetimeVersion = CurrentPageLifetimeVersion;
+        var hasLoadingLock = false;
+
         try
         {
-            await _calendarLoadingSemaphore.WaitAsync().ConfigureAwait(false);
+            hasLoadingLock = await WaitForCalendarLoadingLockAsync(lifetimeVersion).ConfigureAwait(false);
+
+            if (!hasLoadingLock)
+                return;
 
             if (DayRanges == null || DayRanges.Count == 0)
                 return;
 
             RefreshSettings();
-
+            await RenderDatesAsync(CalendarInitInitiative.User,
-            foreach (var dayRange in DayRanges)
+                                   GetRestoreDate(),
-            {
+                                   CalendarLoadDirection.Replace,
-                await InitializeCalendarEventsForDayRangeAsync(dayRange).ConfigureAwait(false);
+                                   lifetimeVersion).ConfigureAwait(false);
-            }
+        }
-
+        catch (OperationCanceledException)
-            FilterActiveCalendars(DayRanges);
+        {
+        }
+        catch (COMException) when (!IsPageActive(lifetimeVersion))
+        {
+        }
+        catch (ObjectDisposedException) when (!IsPageActive(lifetimeVersion))
+        {
         }
         catch (Exception ex)
         {
@@ -785,7 +1075,10 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
         }
         finally
         {
-            _calendarLoadingSemaphore.Release();
+            if (hasLoadingLock)
+            {
+                ReleaseCalendarLoadingLock();
+            }
         }
     }
 
@@ -891,9 +1184,15 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
 
     private async Task LoadMoreAsync()
     {
+        var lifetimeVersion = CurrentPageLifetimeVersion;
+        var hasLoadingLock = false;
+
         try
         {
-            await _calendarLoadingSemaphore.WaitAsync();
+            hasLoadingLock = await WaitForCalendarLoadingLockAsync(lifetimeVersion).ConfigureAwait(false);
+
+            if (!hasLoadingLock)
+                return;
 
             // Depending on the selected index, we'll load more dates.
             // Day ranges may change while the async update is in progress.
@@ -902,20 +1201,33 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
 
             if (SelectedDateRangeIndex == 0)
             {
-                await RenderDatesAsync(CalendarInitInitiative.App, calendarLoadDirection: CalendarLoadDirection.Previous);
+                await RenderDatesAsync(CalendarInitInitiative.App, calendarLoadDirection: CalendarLoadDirection.Previous, lifetimeVersion: lifetimeVersion);
             }
             else if (SelectedDateRangeIndex == DayRanges.Count - 1)
             {
-                await RenderDatesAsync(CalendarInitInitiative.App, calendarLoadDirection: CalendarLoadDirection.Next);
+                await RenderDatesAsync(CalendarInitInitiative.App, calendarLoadDirection: CalendarLoadDirection.Next, lifetimeVersion: lifetimeVersion);
             }
         }
-        catch (Exception)
+        catch (OperationCanceledException)
         {
+        }
+        catch (COMException) when (!IsPageActive(lifetimeVersion))
+        {
+        }
+        catch (ObjectDisposedException) when (!IsPageActive(lifetimeVersion))
+        {
+        }
+        catch (Exception ex)
+        {
+            Debug.WriteLine(ex);
             Debugger.Break();
         }
         finally
         {
-            _calendarLoadingSemaphore.Release();
+            if (hasLoadingLock)
+            {
+                ReleaseCalendarLoadingLock();
+            }
         }
     }
 
@@ -1042,9 +1354,14 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
 
     public async void Receive(AccountRemovedMessage message)
     {
+        var lifetimeVersion = CurrentPageLifetimeVersion;
+
+        if (!IsPageActive(lifetimeVersion))
+            return;
+
         var removedAccountId = message.Account.Id;
 
-        await ExecuteUIThread(() =>
+        await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () =>
         {
             foreach (var dayRange in DayRanges)
             {
@@ -1066,6 +1383,7 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
     protected override async void OnCalendarItemDeleted(CalendarItem calendarItem)
     {
         base.OnCalendarItemDeleted(calendarItem);
+        var lifetimeVersion = CurrentPageLifetimeVersion;
 
         Debug.WriteLine($"Calendar item deleted: {calendarItem.Id}");
 
@@ -1080,7 +1398,7 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
         }
 
         // Remove the event and its occurrences from all visible date ranges.
-        await ExecuteUIThread(() =>
+        await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () =>
         {
             foreach (var dayRange in DayRanges)
             {
@@ -1097,6 +1415,7 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
     protected override async void OnCalendarItemUpdated(CalendarItem calendarItem, CalendarItemUpdateSource source)
     {
         base.OnCalendarItemUpdated(calendarItem, source);
+        var lifetimeVersion = CurrentPageLifetimeVersion;
         Debug.WriteLine($"Calendar item updated: {calendarItem.Id}");
 
         // Local-only calendar operations are persisted immediately without real network I/O.
@@ -1128,7 +1447,7 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
             .Where(a => a.Period.OverlapsWith(calendarItem.Period))
             .ToList();
 
-        await ExecuteUIThread(() =>
+        await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () =>
         {
             if (source == CalendarItemUpdateSource.ClientUpdated)
             {
@@ -1178,12 +1497,13 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
             }
         });
 
-        FilterActiveCalendars(DayRanges);
+        await FilterActiveCalendarsAsync(DayRanges).ConfigureAwait(false);
     }
 
     protected override async void OnCalendarItemAdded(CalendarItem calendarItem)
     {
         base.OnCalendarItemAdded(calendarItem);
+        var lifetimeVersion = CurrentPageLifetimeVersion;
         Debug.WriteLine($"Calendar item added: {calendarItem.Id}");
 
         // Series master events should not be visible on the UI.
@@ -1209,7 +1529,7 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
             {
                 Debug.WriteLine($"Mapped pending busy item {pendingMatch.Id} with synced server event {calendarItem.Id}.");
 
-                await ExecuteUIThread(() =>
+                await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () =>
                 {
                     RemoveCalendarItemEverywhere(pendingMatch.Id);
                 });
@@ -1230,17 +1550,19 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
                 IsBusy = string.IsNullOrEmpty(calendarItem.RemoteEventId)
             };
 
-            await ExecuteUIThread(() =>
+            await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () =>
             {
                 calendarDay.EventsCollection.AddCalendarItem(calendarItemViewModel);
             });
         }
 
-        FilterActiveCalendars(DayRanges);
+        await FilterActiveCalendarsAsync(DayRanges).ConfigureAwait(false);
     }
 
     private async Task RestoreVisibleRecurringSeriesInstancesAsync(CalendarItem recurringParent)
     {
+        var lifetimeVersion = CurrentPageLifetimeVersion;
+
         if (DayRanges.DisplayRange == null || recurringParent?.AssignedCalendar == null)
             return;
 
@@ -1254,7 +1576,7 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
         if (!recurringChildren.Any())
             return;
 
-        await ExecuteUIThread(() =>
+        await ExecuteUIThreadIfActiveAsync(lifetimeVersion, () =>
         {
             foreach (var child in recurringChildren)
             {
@@ -1277,6 +1599,6 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
             }
         });
 
-        FilterActiveCalendars(DayRanges);
+        await FilterActiveCalendarsAsync(DayRanges).ConfigureAwait(false);
     }
 }

Wino.Core.Domain/Interfaces/IShellClient.cs

@@ -69,5 +69,5 @@ public interface IShellHost
 {
     bool HasShellContent { get; }
 
-    void ActivateMode(WinoApplicationMode mode, bool isInitialActivation);
+    void ActivateMode(WinoApplicationMode mode, ShellModeActivationContext activationContext);
 }

Wino.Core.ViewModels/SettingOptionsPageViewModel.cs

@@ -58,22 +58,14 @@ public partial class SettingOptionsPageViewModel : CoreBaseViewModel
         });
     }
 
-    [RelayCommand]
-    private void GoAccountSettings() => Messenger.Send<NavigateManageAccountsRequested>();
-
     [RelayCommand]
     public void NavigateSubDetail(object type)
     {
         if (type is WinoPage pageType)
         {
-            if (pageType == WinoPage.AccountManagementPage)
-            {
-                GoAccountSettings();
-                return;
-            }
-
             string pageTitle = pageType switch
             {
+                WinoPage.ManageAccountsPage => Translator.SettingsManageAccountSettings_Title,
                 WinoPage.PersonalizationPage => Translator.SettingsPersonalization_Title,
                 WinoPage.AboutPage => Translator.SettingsAbout_Title,
                 WinoPage.MessageListPage => Translator.SettingsMessageList_Title,

Wino.Mail.ViewModels/MailAppShellViewModel.cs

@@ -30,7 +30,6 @@ namespace Wino.Mail.ViewModels;
 
 public partial class MailAppShellViewModel : MailBaseViewModel,
     IMailShellClient,
-    IRecipient<NavigateManageAccountsRequested>,
     IRecipient<MailtoProtocolMessageRequested>,
     IRecipient<RefreshUnreadCountsMessage>,
     IRecipient<AccountsMenuRefreshRequested>,
@@ -232,31 +231,19 @@ public partial class MailAppShellViewModel : MailBaseViewModel,
         base.OnNavigatedTo(mode, parameters);
 
         var activationContext = parameters as ShellModeActivationContext;
-        var isModeResetActivation = activationContext != null;
         var shouldRunStartupFlows = activationContext?.IsInitialActivation ?? true;
+        var hasExistingMenuItems = MenuItems?.Any() == true;
 
         PreferencesService.PreferenceChanged -= PreferencesServiceChanged;
         PreferencesService.PreferenceChanged += PreferencesServiceChanged;
 
-        if (mode == NavigationMode.Back && !isModeResetActivation)
-        {
-            // Preserve current mail/folder selection and active rendering page when
-            // switching back from Calendar mode. Recreating menu/folder state here
-            // causes a folder reload, which clears selection and disposes reader page.
-            // Rehydrate only if menu state is unexpectedly empty.
-            if (MenuItems?.Any() != true || FooterItems?.Any() != true)
-            {
-                await CreateFooterItemsAsync();
-                await RecreateMenuItemsAsync();
-                await RestoreSelectedAccountAfterMenuRefreshAsync(false);
-            }
-
-            return;
-        }
-
         await CreateFooterItemsAsync(true);
 
-        await RecreateMenuItemsAsync();
+        if (!hasExistingMenuItems)
+        {
+            await RecreateMenuItemsAsync();
+        }
+
         await ProcessLaunchOptionsAsync();
         await ValidateWebView2RuntimeAsync();
 
@@ -934,8 +921,6 @@ public partial class MailAppShellViewModel : MailBaseViewModel,
         accountMenuItem.UpdateAccount(accountModel);
     }
 
-    public void Receive(NavigateManageAccountsRequested message) => SelectedMenuItem = ManageAccountsMenuItem;
-
     public async void Receive(MailtoProtocolMessageRequested message)
     {
         var accounts = await _accountService.GetAccountsAsync();
@@ -1173,7 +1158,6 @@ public partial class MailAppShellViewModel : MailBaseViewModel,
         Messenger.Register<AccountCreatedMessage>(this);
         Messenger.Register<AccountRemovedMessage>(this);
         Messenger.Register<AccountUpdatedMessage>(this);
-        Messenger.Register<NavigateManageAccountsRequested>(this);
         Messenger.Register<MailtoProtocolMessageRequested>(this);
         Messenger.Register<RefreshUnreadCountsMessage>(this);
         Messenger.Register<AccountsMenuRefreshRequested>(this);
@@ -1192,7 +1176,6 @@ public partial class MailAppShellViewModel : MailBaseViewModel,
         Messenger.Unregister<AccountCreatedMessage>(this);
         Messenger.Unregister<AccountRemovedMessage>(this);
         Messenger.Unregister<AccountUpdatedMessage>(this);
-        Messenger.Unregister<NavigateManageAccountsRequested>(this);
         Messenger.Unregister<MailtoProtocolMessageRequested>(this);
         Messenger.Unregister<RefreshUnreadCountsMessage>(this);
         Messenger.Unregister<AccountsMenuRefreshRequested>(this);

Wino.Mail.ViewModels/MailListPageViewModel.cs

@@ -17,8 +17,8 @@ using Wino.Core.Domain.Entities.Mail;
 using Wino.Core.Domain.Entities.Shared;
 using Wino.Core.Domain.Enums;
 using Wino.Core.Domain.Interfaces;
-using Wino.Core.Domain.Models.Folders;
 using Wino.Core.Domain.Models;
+using Wino.Core.Domain.Models.Folders;
 using Wino.Core.Domain.Models.MailItem;
 using Wino.Core.Domain.Models.Menus;
 using Wino.Core.Domain.Models.Navigation;
@@ -198,30 +198,6 @@ public partial class MailListPageViewModel : MailBaseViewModel,
         SelectedSortingOption = SortingOptions[0];
 
         MailListLength = statePersistenceService.MailListPaneLength;
-
-        //_selectionChangedThrottler = new ThrottledEventHandler(100, () =>
-        //{
-        //    _ = ExecuteUIThread(() =>
-        //    {
-        //        if (MailCollection.SelectedVisibleCount == 1)
-        //        {
-        //            ActiveMailItemChanged(MailCollection.SelectedVisibleItems.ElementAt(0));
-        //        }
-        //        else
-        //        {
-        //            // At this point, either we don't have any item selected 
-        //            // or we have multiple item selected. In either case
-        //            // there should be no active item.
-
-        //            ActiveMailItemChanged(null);
-        //        }
-
-        //        NotifyItemSelected();
-        //        SetupTopBarActions();
-        //    });
-
-        //    ThrottledSelectionChanged?.Invoke(this, EventArgs.Empty);
-        //});
     }
 
     public override void OnNavigatedTo(NavigationMode mode, object parameters)

Wino.Mail.WinUI/App.xaml.cs

@@ -177,7 +177,7 @@ public partial class App : WinoApplication,
         services.AddTransient(typeof(SignatureAndEncryptionPageViewModel));
         services.AddTransient(typeof(EmailTemplatesPageViewModel));
         services.AddTransient(typeof(CreateEmailTemplatePageViewModel));
-        services.AddTransient(typeof(CalendarPageViewModel));
+        services.AddSingleton(typeof(CalendarPageViewModel));
         services.AddTransient(typeof(CalendarSettingsPageViewModel));
         services.AddTransient(typeof(CalendarAccountSettingsPageViewModel));
         services.AddTransient(typeof(EventDetailsPageViewModel));

Wino.Mail.WinUI/Controls/AppModeFooterSwitcherControl.xaml

@@ -2,6 +2,7 @@
     x:Class="Wino.Mail.WinUI.Controls.AppModeFooterSwitcherControl"
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:animatedvisuals="using:Microsoft.UI.Xaml.Controls.AnimatedVisuals"
     xmlns:controls="using:CommunityToolkit.WinUI.Controls"
     xmlns:domain="using:Wino.Core.Domain"
     Loaded="ControlLoaded"
@@ -27,6 +28,11 @@
                     <FontIcon FontFamily="{StaticResource SymbolThemeFontFamily}" Glyph="&#xE716;" />
                 </controls:SegmentedItem.Icon>
             </controls:SegmentedItem>
+            <controls:SegmentedItem ToolTipService.ToolTip="{x:Bind domain:Translator.MenuSettings, Mode=OneWay}">
+                <controls:SegmentedItem.Icon>
+                    <SymbolIcon Symbol="Setting" />
+                </controls:SegmentedItem.Icon>
+            </controls:SegmentedItem>
         </controls:Segmented>
     </Grid>
 </UserControl>

Wino.Mail.WinUI/Controls/AppModeFooterSwitcherControl.xaml.cs

@@ -4,6 +4,7 @@ using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Controls;
 using Wino.Core.Domain.Enums;
 using Wino.Core.Domain.Interfaces;
+using Wino.Core.Domain;
 
 namespace Wino.Mail.WinUI.Controls;
 
@@ -44,6 +45,13 @@ public sealed partial class AppModeFooterSwitcherControl : UserControl
         if (_isUpdatingSelection)
             return;
 
+        if (ModeSegmentedControl.SelectedIndex == 3)
+        {
+            _navigationService.Navigate(WinoPage.SettingsPage);
+            UpdateSelection(_statePersistenceService.ApplicationMode);
+            return;
+        }
+
         var selectedMode = ModeSegmentedControl.SelectedIndex switch
         {
             1 => WinoApplicationMode.Calendar,

Wino.Mail.WinUI/Controls/Calendar/CustomCalendarFlipView.cs

@@ -49,6 +49,7 @@ public partial class CustomCalendarFlipView : FlipView
         HideButton(PreviousButtonVertical);
         HideButton(NextButtonVertical);
 
+        SelectionChanged -= FlipViewSelectionChanged;
         SelectionChanged += FlipViewSelectionChanged;
     }
 

Wino.Mail.WinUI/Controls/Calendar/WinoCalendarControl.cs

@@ -13,7 +13,7 @@ using Wino.Helpers;
 
 namespace Wino.Calendar.Controls;
 
-public partial class WinoCalendarControl : Control
+public partial class WinoCalendarControl : Control, IDisposable
 {
     private const string PART_WinoFlipView = nameof(PART_WinoFlipView);
     private const string PART_IdleGrid = nameof(PART_IdleGrid);
@@ -93,6 +93,12 @@ public partial class WinoCalendarControl : Control
     partial void OnIsFlipIdleChanged(bool newValue)
         => UpdateIdleState();
 
+    partial void OnDayRangesChanged(ObservableCollection<DayRangeRenderModel>? newValue)
+        => EnsureStableSelection();
+
+    partial void OnSelectedFlipViewDayRangeChanged(DayRangeRenderModel? newValue)
+        => EnsureStableSelection();
+
     partial void OnActiveScrollViewerPropertyChanged(DependencyPropertyChangedEventArgs e)
     {
         var newValue = e.NewValue as ScrollViewer;
@@ -200,6 +206,23 @@ public partial class WinoCalendarControl : Control
         if (InternalFlipView != null)
         {
             InternalFlipView.ProgrammaticNavigationCompleted -= InternalFlipViewProgrammaticNavigationCompleted;
+
+            if (InternalFlipView is IDisposable disposableFlipView)
+            {
+                disposableFlipView.Dispose();
+            }
+        }
+
+        if (_previousScrollViewer != null)
+        {
+            DeregisterScrollChanges(_previousScrollViewer);
+            _previousScrollViewer = null;
+        }
+
+        if (_previousCanvas != null)
+        {
+            DeregisterCanvas(_previousCanvas);
+            _previousCanvas = null;
         }
 
         InternalFlipView = GetTemplateChild(PART_WinoFlipView) as WinoCalendarFlipView;
@@ -213,6 +236,7 @@ public partial class WinoCalendarControl : Control
         UpdateIdleState();
         ManageCalendarOrientation();
         ManageDisplayType();
+        EnsureStableSelection();
     }
 
     private void InternalFlipViewProgrammaticNavigationCompleted(object? sender, ProgrammaticNavigationCompletedEventArgs e)
@@ -233,6 +257,33 @@ public partial class WinoCalendarControl : Control
         }
     }
 
+    private void EnsureStableSelection()
+    {
+        if (InternalFlipView == null || DayRanges == null || DayRanges.Count == 0)
+            return;
+
+        var targetIndex = SelectedFlipViewIndex;
+
+        if (SelectedFlipViewDayRange != null)
+        {
+            var selectedRangeIndex = DayRanges.IndexOf(SelectedFlipViewDayRange);
+            if (selectedRangeIndex >= 0)
+            {
+                targetIndex = selectedRangeIndex;
+            }
+        }
+
+        if (targetIndex < 0 || targetIndex >= DayRanges.Count)
+        {
+            targetIndex = 0;
+        }
+
+        if (InternalFlipView.SelectedIndex != targetIndex)
+        {
+            InternalFlipView.SelectedIndex = targetIndex;
+        }
+    }
+
     private void ActiveTimelineCellUnselected(object? sender, TimelineCellUnselectedArgs e)
         => TimelineCellUnselected?.Invoke(this, e);
 
@@ -291,4 +342,40 @@ public partial class WinoCalendarControl : Control
     {
         return this.FindDescendants<CalendarItemControl>().FirstOrDefault(a => a.CalendarItem == calendarItemViewModel)!;
     }
+
+    public void Dispose()
+    {
+        SizeChanged -= CalendarSizeChanged;
+
+        if (_previousScrollViewer != null)
+        {
+            DeregisterScrollChanges(_previousScrollViewer);
+            _previousScrollViewer = null;
+        }
+
+        if (_previousCanvas != null)
+        {
+            DeregisterCanvas(_previousCanvas);
+            _previousCanvas = null;
+        }
+
+        if (InternalFlipView != null)
+        {
+            InternalFlipView.ProgrammaticNavigationCompleted -= InternalFlipViewProgrammaticNavigationCompleted;
+
+            if (InternalFlipView is IDisposable disposableFlipView)
+            {
+                disposableFlipView.Dispose();
+            }
+
+            InternalFlipView = null;
+        }
+
+        IdleGrid = null;
+        ActiveCanvas = null;
+        ActiveScrollViewer = null;
+        TimelineCellSelected = null;
+        TimelineCellUnselected = null;
+        ScrollPositionChanging = null;
+    }
 }

Wino.Mail.WinUI/Controls/Calendar/WinoCalendarFlipView.cs

@@ -10,7 +10,7 @@ using Wino.Core.Domain.Models.Calendar;
 
 namespace Wino.Calendar.Controls;
 
-public partial class WinoCalendarFlipView : CustomCalendarFlipView
+public partial class WinoCalendarFlipView : CustomCalendarFlipView, IDisposable
 {
     public static readonly DependencyProperty IsIdleProperty = DependencyProperty.Register(nameof(IsIdle), typeof(bool), typeof(WinoCalendarFlipView), new PropertyMetadata(true));
     public static readonly DependencyProperty ActiveCanvasProperty = DependencyProperty.Register(nameof(ActiveCanvas), typeof(WinoDayTimelineCanvas), typeof(WinoCalendarFlipView), new PropertyMetadata(null));
@@ -50,10 +50,11 @@ public partial class WinoCalendarFlipView : CustomCalendarFlipView
     internal event EventHandler<ProgrammaticNavigationCompletedEventArgs>? ProgrammaticNavigationCompleted;
 
     private INotifyCollectionChanged? _trackedItemsSource;
+    private readonly long _itemsSourceCallbackToken;
 
     public WinoCalendarFlipView()
     {
-        RegisterPropertyChangedCallback(ItemsSourceProperty, new DependencyPropertyChangedCallback(OnItemsSourceChanged));
+        _itemsSourceCallbackToken = RegisterPropertyChangedCallback(ItemsSourceProperty, new DependencyPropertyChangedCallback(OnItemsSourceChanged));
     }
 
     private static void OnItemsSourceChanged(DependencyObject d, DependencyProperty e)
@@ -207,6 +208,18 @@ public partial class WinoCalendarFlipView : CustomCalendarFlipView
 
     private ObservableRangeCollection<DayRangeRenderModel>? GetItemsSource()
         => ItemsSource as ObservableRangeCollection<DayRangeRenderModel>;
+
+    public void Dispose()
+    {
+        if (_trackedItemsSource != null)
+        {
+            _trackedItemsSource.CollectionChanged -= ItemsSourceUpdated;
+            _trackedItemsSource = null;
+        }
+
+        UnregisterPropertyChangedCallback(ItemsSourceProperty, _itemsSourceCallbackToken);
+        ProgrammaticNavigationCompleted = null;
+    }
 }
 
 internal sealed class ProgrammaticNavigationCompletedEventArgs : EventArgs

Wino.Mail.WinUI/Controls/Calendar/WinoCalendarView.cs

@@ -10,7 +10,7 @@ using Wino.Helpers;
 
 namespace Wino.Calendar.Controls;
 
-public partial class WinoCalendarView : Control
+public partial class WinoCalendarView : Control, IDisposable
 {
     private const string PART_DayViewItemBorder = nameof(PART_DayViewItemBorder);
     private const string PART_CalendarView = nameof(PART_CalendarView);
@@ -54,6 +54,7 @@ public partial class WinoCalendarView : Control
 
 
     private CalendarView? CalendarView;
+    private long _displayModeCallbackToken = -1;
 
     public WinoCalendarView()
     {
@@ -64,6 +65,17 @@ public partial class WinoCalendarView : Control
     {
         base.OnApplyTemplate();
 
+        if (CalendarView != null)
+        {
+            CalendarView.SelectedDatesChanged -= InternalCalendarViewSelectionChanged;
+
+            if (_displayModeCallbackToken != -1)
+            {
+                CalendarView.UnregisterPropertyChangedCallback(CalendarView.DisplayModeProperty, _displayModeCallbackToken);
+                _displayModeCallbackToken = -1;
+            }
+        }
+
         CalendarView = GetTemplateChild(PART_CalendarView) as CalendarView;
 
         Guard.IsNotNull(CalendarView, nameof(CalendarView));
@@ -78,7 +90,7 @@ public partial class WinoCalendarView : Control
         // Everytime display mode changes, update the visible date range backgrounds.
         // If users go back from year -> month -> day, we need to update the visible date range backgrounds.
 
-        CalendarView.RegisterPropertyChangedCallback(CalendarView.DisplayModeProperty, (s, e) => UpdateVisibleDateRangeBackgrounds());
+        _displayModeCallbackToken = CalendarView.RegisterPropertyChangedCallback(CalendarView.DisplayModeProperty, (s, e) => UpdateVisibleDateRangeBackgrounds());
     }
 
     private void InternalCalendarViewSelectionChanged(CalendarView sender, CalendarViewSelectedDatesChangedEventArgs args)
@@ -147,4 +159,20 @@ public partial class WinoCalendarView : Control
             }
         }
     }
+
+    public void Dispose()
+    {
+        if (CalendarView == null)
+            return;
+
+        CalendarView.SelectedDatesChanged -= InternalCalendarViewSelectionChanged;
+
+        if (_displayModeCallbackToken != -1)
+        {
+            CalendarView.UnregisterPropertyChangedCallback(CalendarView.DisplayModeProperty, _displayModeCallbackToken);
+            _displayModeCallbackToken = -1;
+        }
+
+        CalendarView = null;
+    }
 }

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/Services/NavigationService.cs

@@ -215,7 +215,10 @@ public class NavigationService : NavigationServiceBase, INavigationService
 
         if (coreFrame.Content is IShellHost shell)
         {
-            shell.ActivateMode(mode, isInitialShellNavigation);
+            shell.ActivateMode(mode, new ShellModeActivationContext
+            {
+                IsInitialActivation = isInitialShellNavigation
+            });
             return true;
         }
 

Wino.Mail.WinUI/ShellWindow.xaml

@@ -93,7 +93,7 @@
         <Frame
             x:Name="MainShellFrame"
             Grid.Row="1"
-            CacheSize="2"
+            CacheSize="0"
             Navigated="MainFrameNavigated" />
 
         <coreControls:WinoInfoBar

Wino.Mail.WinUI/Styles/CalendarShellNavigationViewStyle.xaml

@@ -4,8 +4,8 @@
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
     xmlns:controls="using:Microsoft.UI.Xaml.Controls"
     xmlns:local="using:Wino.Mail.WinUI.Styles"
-    xmlns:winoControls="using:Wino.Mail.WinUI.Controls"
+    xmlns:primitives="using:Microsoft.UI.Xaml.Controls.Primitives"
-    xmlns:primitives="using:Microsoft.UI.Xaml.Controls.Primitives">
+    xmlns:winoControls="using:Wino.Mail.WinUI.Controls">
 
     <Style x:Key="CalendarShellNavigationViewStyle" TargetType="controls:NavigationView">
         <Setter Property="PaneToggleButtonStyle" Value="{StaticResource PaneToggleButtonStyle}" />

Wino.Mail.WinUI/ViewModels/WinoAppShellViewModel.cs

@@ -78,18 +78,6 @@ public sealed class WinoAppShellViewModel : CoreBaseViewModel, IShellViewModel
         }
     }
 
-    protected override void OnDispatcherAssigned()
-    {
-        base.OnDispatcherAssigned();
-
-        foreach (var client in _shellClients.Values)
-        {
-            client.Dispatcher = Dispatcher;
-        }
-
-        OnPropertyChanged(nameof(CurrentMenuItems));
-    }
-
     public override void OnNavigatedTo(Core.Domain.Models.Navigation.NavigationMode mode, object parameters)
     {
         base.OnNavigatedTo(mode, parameters);

Wino.Mail.WinUI/Views/Abstract/CalendarAppShellAbstract .cs

@@ -7,6 +7,6 @@ public abstract class CalendarAppShellAbstract : BasePage<CalendarAppShellViewMo
 {
     protected CalendarAppShellAbstract()
     {
-        NavigationCacheMode = Microsoft.UI.Xaml.Navigation.NavigationCacheMode.Enabled;
+        NavigationCacheMode = Microsoft.UI.Xaml.Navigation.NavigationCacheMode.Disabled;
     }
 }

Wino.Mail.WinUI/Views/Abstract/CalendarPageAbstract.cs

@@ -7,6 +7,6 @@ public abstract class CalendarPageAbstract : BasePage<CalendarPageViewModel>
 {
     protected CalendarPageAbstract()
     {
-        NavigationCacheMode = Microsoft.UI.Xaml.Navigation.NavigationCacheMode.Enabled;
+        NavigationCacheMode = Microsoft.UI.Xaml.Navigation.NavigationCacheMode.Disabled;
     }
 }

Wino.Mail.WinUI/Views/Abstract/ContactsAppShellAbstract.cs

@@ -4,6 +4,6 @@ public abstract class ContactsAppShellAbstract : BasePage
 {
     protected ContactsAppShellAbstract()
     {
-        NavigationCacheMode = Microsoft.UI.Xaml.Navigation.NavigationCacheMode.Enabled;
+        NavigationCacheMode = Microsoft.UI.Xaml.Navigation.NavigationCacheMode.Disabled;
     }
 }

Wino.Mail.WinUI/Views/Abstract/ContactsPageAbstract.cs

@@ -1,6 +1,13 @@
+using Microsoft.UI.Xaml.Navigation;
 using Wino.Mail.WinUI;
 using Wino.Mail.ViewModels;
 
 namespace Wino.Views.Abstract;
 
-public abstract class ContactsPageAbstract : BasePage<ContactsPageViewModel> { }
+public abstract class ContactsPageAbstract : BasePage<ContactsPageViewModel>
+{
+    protected ContactsPageAbstract()
+    {
+        NavigationCacheMode = NavigationCacheMode.Disabled;
+    }
+}

Wino.Mail.WinUI/Views/Abstract/MailAppShellAbstract.cs

@@ -7,6 +7,6 @@ public abstract class MailAppShellAbstract : BasePage<MailAppShellViewModel>
 {
     protected MailAppShellAbstract()
     {
-        NavigationCacheMode = Microsoft.UI.Xaml.Navigation.NavigationCacheMode.Enabled;
+        NavigationCacheMode = Microsoft.UI.Xaml.Navigation.NavigationCacheMode.Disabled;
     }
 }

Wino.Mail.WinUI/Views/Abstract/MailListPageAbstract.cs

@@ -1,6 +1,13 @@
+using Microsoft.UI.Xaml.Navigation;
 using Wino.Mail.WinUI;
 using Wino.Mail.ViewModels;
 
 namespace Wino.Views.Abstract;
 
-public partial class MailListPageAbstract : BasePage<MailListPageViewModel>;
+public partial class MailListPageAbstract : BasePage<MailListPageViewModel>
+{
+    protected MailListPageAbstract()
+    {
+        NavigationCacheMode = NavigationCacheMode.Disabled;
+    }
+}

Wino.Mail.WinUI/Views/Abstract/SettingsPageAbstract.cs

@@ -1,6 +1,13 @@
+using Microsoft.UI.Xaml.Navigation;
 using Wino.Mail.WinUI;
 using Wino.Core.ViewModels;
 
 namespace Wino.Views.Abstract;
 
-public abstract class SettingsPageAbstract : BasePage<SettingsPageViewModel> { }
+public abstract class SettingsPageAbstract : BasePage<SettingsPageViewModel>
+{
+    protected SettingsPageAbstract()
+    {
+        NavigationCacheMode = NavigationCacheMode.Disabled;
+    }
+}

Wino.Mail.WinUI/Views/Abstract/WinoAppShellAbstract.cs

@@ -6,6 +6,6 @@ public abstract class WinoAppShellAbstract : BasePage<WinoAppShellViewModel>
 {
     protected WinoAppShellAbstract()
     {
-        NavigationCacheMode = Microsoft.UI.Xaml.Navigation.NavigationCacheMode.Enabled;
+        NavigationCacheMode = Microsoft.UI.Xaml.Navigation.NavigationCacheMode.Disabled;
     }
 }

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

@@ -17,6 +17,8 @@
     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
     xmlns:menu="using:Wino.Core.Domain.MenuItems"
     xmlns:muxc="using:Microsoft.UI.Xaml.Controls"
+    Loaded="OnLoaded"
+    PreviewKeyDown="OnPreviewKeyDown"
     mc:Ignorable="d">
 
     <Page.Resources>
@@ -312,7 +314,7 @@
                 <Frame
                     x:Name="InnerShellFrame"
                     Padding="0,0,7,7"
-                    CacheSize="2"
+                    CacheSize="0"
                     IsNavigationStackEnabled="True">
                     <Frame.ContentTransitions>
                         <TransitionCollection>

Wino.Mail.WinUI/Views/Calendar/CalendarAppShell.xaml.cs

@@ -25,8 +25,6 @@ public sealed partial class CalendarAppShell : CalendarAppShellAbstract,
     public CalendarAppShell()
     {
         InitializeComponent();
-        PreviewKeyDown += OnPreviewKeyDown;
-        Loaded += OnLoaded;
 
         ManageCalendarDisplayType(ViewModel.StatePersistenceService.CalendarDisplayType);
     }
@@ -83,6 +81,14 @@ public sealed partial class CalendarAppShell : CalendarAppShellAbstract,
     {
         base.OnNavigatedFrom(e);
 
+        InnerShellFrame.BackStack.Clear();
+        InnerShellFrame.ForwardStack.Clear();
+
+        if (InnerShellFrame.Content is IDisposable disposableContent)
+        {
+            disposableContent.Dispose();
+        }
+
         Bindings.StopTracking();
     }
 

Wino.Mail.WinUI/Views/Calendar/CalendarPage.xaml.cs

@@ -26,6 +26,24 @@ public sealed partial class CalendarPage : CalendarPageAbstract,
         ViewModel.DetailsShowCalendarItemChanged += CalendarItemDetailContextChanged;
     }
 
+    protected override void OnNavigatingFrom(NavigatingCancelEventArgs e)
+    {
+        base.OnNavigatingFrom(e);
+
+        ViewModel.DetailsShowCalendarItemChanged -= CalendarItemDetailContextChanged;
+        QuickEventPopupDialog.IsOpen = false;
+        EventDetailsPopup.IsOpen = false;
+        EventDetailsPopup.PlacementTarget = null;
+        CalendarControl.ResetTimelineSelection();
+
+        if (CalendarControl is IDisposable disposableCalendarControl)
+        {
+            disposableCalendarControl.Dispose();
+        }
+
+        Bindings.StopTracking();
+    }
+
     private void CalendarItemDetailContextChanged(object? sender, EventArgs e)
     {
         if (ViewModel.DisplayDetailsCalendarItemViewModel != null)
@@ -59,16 +77,29 @@ public sealed partial class CalendarPage : CalendarPageAbstract,
         WeakReferenceMessenger.Default.Unregister<GoPreviousDateRequestedMessage>(this);
     }
 
-    public void Receive(ScrollToHourMessage message) => CalendarControl.NavigateToHour(message.TimeSpan);
+    public void Receive(ScrollToHourMessage message) => DispatcherQueue.TryEnqueue(() => CalendarControl.NavigateToHour(message.TimeSpan));
-    public void Receive(ScrollToDateMessage message) => CalendarControl.NavigateToDay(message.Date);
+    public void Receive(ScrollToDateMessage message) => DispatcherQueue.TryEnqueue(() => CalendarControl.NavigateToDay(message.Date));
-    public void Receive(GoNextDateRequestedMessage message) => CalendarControl.GoNextRange();
+    public void Receive(GoNextDateRequestedMessage message) => DispatcherQueue.TryEnqueue(() => CalendarControl.GoNextRange());
-    public void Receive(GoPreviousDateRequestedMessage message) => CalendarControl.GoPreviousRange();
+    public void Receive(GoPreviousDateRequestedMessage message) => DispatcherQueue.TryEnqueue(() => CalendarControl.GoPreviousRange());
 
     protected override void OnNavigatedTo(NavigationEventArgs e)
     {
         base.OnNavigatedTo(e);
 
-        if (e.NavigationMode == NavigationMode.Back) return;
+        if (e.NavigationMode == NavigationMode.Back)
+        {
+            if (ViewModel.RestoreVisibleState())
+            {
+                var restoreDate = ViewModel.GetRestoreDate();
+                DispatcherQueue.TryEnqueue(() => CalendarControl.NavigateToDay(restoreDate));
+            }
+            else
+            {
+                WeakReferenceMessenger.Default.Send(new LoadCalendarMessage(DateTime.Now.Date, CalendarInitInitiative.App));
+            }
+
+            return;
+        }
 
         if (e.Parameter is CalendarPageNavigationArgs args)
         {

Wino.Mail.WinUI/Views/SettingOptionsPage.xaml

@@ -108,12 +108,11 @@
                             Grid.Column="2"
                             Command="{x:Bind ViewModel.NavigateExternalCommand}"
                             CommandParameter="Store"
-                            Style="{StaticResource AccentButtonStyle}"
                             ToolTipService.ToolTip="{x:Bind domain:Translator.SettingsStore_Title}">
                             <Viewbox Width="18" Height="18">
                                 <Path
                                     Data="F1 M 19.003906 3.251953 L 19.003906 15.947266 C 19.003906 16.357422 18.920898 16.748047 18.754883 17.119141 C 18.588867 17.490234 18.367512 17.814127 18.09082 18.09082 C 17.814127 18.367514 17.490234 18.588867 17.119141 18.754883 C 16.748047 18.920898 16.357422 19.003906 15.947266 19.003906 L 3.056641 19.003906 C 2.646484 19.003906 2.255859 18.920898 1.884766 18.754883 C 1.513672 18.588867 1.189779 18.367514 0.913086 18.09082 C 0.636393 17.814127 0.415039 17.490234 0.249023 17.119141 C 0.083008 16.748047 0 16.357422 0 15.947266 L 0 3.251953 C 0 3.076172 0.032552 2.913412 0.097656 2.763672 C 0.16276 2.613934 0.252279 2.482098 0.366211 2.368164 C 0.480143 2.254232 0.611979 2.164715 0.761719 2.099609 C 0.911458 2.034506 1.074219 2.001953 1.25 2.001953 L 4.003906 2.001953 L 4.003906 0.996094 C 4.003906 0.859375 4.029948 0.730795 4.082031 0.610352 C 4.134114 0.48991 4.205729 0.384115 4.296875 0.292969 C 4.388021 0.201824 4.493815 0.130209 4.614258 0.078125 C 4.7347 0.026043 4.863281 0 5 0 L 14.003906 0 C 14.140624 0 14.269205 0.026043 14.389648 0.078125 C 14.510091 0.130209 14.615885 0.201824 14.707031 0.292969 C 14.798177 0.384115 14.869791 0.48991 14.921875 0.610352 C 14.973957 0.730795 14.999999 0.859375 15 0.996094 L 15 2.001953 L 17.753906 2.001953 C 17.923176 2.001953 18.084309 2.034506 18.237305 2.099609 C 18.390299 2.164715 18.523762 2.254232 18.637695 2.368164 C 18.751627 2.482098 18.841145 2.615561 18.90625 2.768555 C 18.971354 2.921551 19.003906 3.082684 19.003906 3.251953 Z M 14.003906 0.996094 L 5 0.996094 L 5 2.001953 L 14.003906 2.001953 Z M 5 10 L 9.003906 10 L 9.003906 5.996094 L 5 5.996094 Z M 10 10 L 14.003906 10 L 14.003906 5.996094 L 10 5.996094 Z M 5 15 L 9.003906 15 L 9.003906 10.996094 L 5 10.996094 Z M 10 15 L 14.003906 15 L 14.003906 10.996094 L 10 10.996094 Z "
-                                    Fill="{ThemeResource AccentTextFillColorPrimaryBrush}"
+                                    Fill="{ThemeResource TextFillColorPrimaryBrush}"
                                     Stretch="Uniform" />
                             </Viewbox>
                         </Button>
@@ -128,14 +127,14 @@
                 Description="{x:Bind ViewModel.AccountSummaryText, Mode=OneWay}"
                 Header="{x:Bind domain:Translator.SettingsManageAccountSettings_Title}"
                 IsClickEnabled="True"
-                Tag="{x:Bind enums:WinoPage.AccountManagementPage}">
+                Tag="{x:Bind enums:WinoPage.ManageAccountsPage}">
                 <controls:SettingsCard.HeaderIcon>
                     <FontIcon Foreground="{ThemeResource AccentTextFillColorPrimaryBrush}" Glyph="&#xE77B;" />
                 </controls:SettingsCard.HeaderIcon>
                 <Button
                     Click="SettingOptionClicked"
                     Style="{StaticResource AccentButtonStyle}"
-                    Tag="{x:Bind enums:WinoPage.AccountManagementPage}">
+                    Tag="{x:Bind enums:WinoPage.ManageAccountsPage}">
                     <StackPanel Orientation="Horizontal" Spacing="8">
                         <TextBlock Text="{x:Bind domain:Translator.Buttons_Manage}" />
                         <FontIcon FontSize="12" Glyph="&#xE76C;" />

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

@@ -31,6 +31,9 @@ public sealed partial class SettingsPage : SettingsPageAbstract,
         // Register for frame navigation events to track back button visibility
         SettingsFrame.Navigated -= SettingsFrameNavigated;
         SettingsFrame.Navigated += SettingsFrameNavigated;
+        PageHistory.Clear();
+        SettingsFrame.BackStack.Clear();
+        SettingsFrame.ForwardStack.Clear();
 
         SettingsFrame.Navigate(typeof(SettingOptionsPage), null, new SuppressNavigationTransitionInfo());
 
@@ -53,6 +56,10 @@ public sealed partial class SettingsPage : SettingsPageAbstract,
                 case WinoPage.EmailTemplatesPage:
                     WeakReferenceMessenger.Default.Send(new BreadcrumbNavigationRequested(Translator.SettingsEmailTemplates_Title, WinoPage.EmailTemplatesPage));
                     break;
+                case WinoPage.ManageAccountsPage:
+                case WinoPage.AccountManagementPage:
+                    WeakReferenceMessenger.Default.Send(new BreadcrumbNavigationRequested(Translator.SettingsManageAccountSettings_Title, WinoPage.ManageAccountsPage));
+                    break;
             }
         }
 

Wino.Mail.WinUI/Views/WinoAppShell.xaml

@@ -644,6 +644,7 @@
                 <!--  Main Content  -->
                 <Frame
                     x:Name="InnerShellFrame"
+                    CacheSize="0"
                     Padding="0,0,7,7"
                     IsNavigationStackEnabled="True"
                     Navigated="ShellFrameContentNavigated">

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

@@ -13,6 +13,7 @@ using Microsoft.UI.Xaml.Input;
 using Microsoft.UI.Xaml.Navigation;
 using Windows.Foundation;
 using Wino.Calendar.Controls;
+using Wino.Calendar.Views;
 using Wino.Calendar.ViewModels;
 using Wino.Core.Domain;
 using Wino.Core.Domain.Entities.Mail;
@@ -31,6 +32,9 @@ using Wino.Messaging.Client.Accounts;
 using Wino.Messaging.Client.Calendar;
 using Wino.Messaging.Client.Mails;
 using Wino.Messaging.Client.Shell;
+using Wino.Views.Mail;
+using Wino.Views;
+using Wino.Views.Settings;
 
 namespace Wino.Mail.WinUI.Views;
 
@@ -51,6 +55,11 @@ public sealed partial class WinoAppShell : Views.Abstract.WinoAppShellAbstract,
     {
         InitializeComponent();
 
+        var pageDispatcher = new WinUIDispatcher(DispatcherQueue);
+        ViewModel.MailClient.Dispatcher = pageDispatcher;
+        ViewModel.CalendarClient.Dispatcher = pageDispatcher;
+        ViewModel.GetClient(WinoApplicationMode.Contacts).Dispatcher = pageDispatcher;
+
         ViewModel.MailClient.PropertyChanged += MailClientPropertyChanged;
         ViewModel.CalendarClient.PropertyChanged += CalendarClientPropertyChanged;
         ViewModel.StatePersistenceService.StatePropertyChanged += StatePersistenceServiceChanged;
@@ -66,30 +75,22 @@ public sealed partial class WinoAppShell : Views.Abstract.WinoAppShellAbstract,
 
     public Frame GetShellFrame() => InnerShellFrame;
 
-    public void ActivateMode(WinoApplicationMode mode, bool isInitialActivation)
+    public void ActivateMode(WinoApplicationMode mode, ShellModeActivationContext activationContext)
     {
         if (_activeMode == mode && InnerShellFrame.Content != null)
             return;
 
         DeactivateCurrentMode();
+        ResetShellModeNavigationState();
 
         _activeMode = mode;
         ViewModel.SetCurrentMode(mode);
 
         RefreshNavigationViewBindings(syncMailSelection: mode != WinoApplicationMode.Mail);
 
-        //InnerShellFrame.IsNavigationStackEnabled = mode == WinoApplicationMode.Calendar;
-        //InnerShellFrame.BackStack.Clear();
-        //InnerShellFrame.ForwardStack.Clear();
-
         ApplyModeLayout();
         UpdateTitleBarSubtitle();
 
-        var activationContext = new ShellModeActivationContext
-        {
-            IsInitialActivation = isInitialActivation
-        };
-
         ViewModel.CurrentClient.Activate(activationContext);
 
         ApplyTitleBarContent();
@@ -110,7 +111,10 @@ public sealed partial class WinoAppShell : Views.Abstract.WinoAppShellAbstract,
 
         if (_activeMode == null)
         {
-            ActivateMode(ViewModel.StatePersistenceService.ApplicationMode, true);
+            ActivateMode(ViewModel.StatePersistenceService.ApplicationMode, new ShellModeActivationContext
+            {
+                IsInitialActivation = true
+            });
         }
     }
 
@@ -133,16 +137,30 @@ public sealed partial class WinoAppShell : Views.Abstract.WinoAppShellAbstract,
     {
         if (_activeMode == WinoApplicationMode.Mail)
         {
+            WeakReferenceMessenger.Default.Send(new ClearMailSelectionsRequested());
+            WeakReferenceMessenger.Default.Send(new DisposeRenderingFrameRequested());
+            ViewModel.StatePersistenceService.IsReadingMail = false;
             ViewModel.MailClient.Deactivate();
         }
         else if (_activeMode == WinoApplicationMode.Calendar)
         {
+            ViewModel.StatePersistenceService.IsEventDetailsVisible = false;
             ViewModel.CalendarClient.Deactivate();
         }
         else if (_activeMode == WinoApplicationMode.Contacts)
         {
             ViewModel.CurrentClient.Deactivate();
         }
+
+        DynamicPageShellContentPresenter.Content = null;
+    }
+
+    private void ResetShellModeNavigationState()
+    {
+        ViewModel.StatePersistenceService.IsManageAccountsNavigating = false;
+        ViewModel.StatePersistenceService.IsSettingsNavigating = false;
+        InnerShellFrame.BackStack.Clear();
+        InnerShellFrame.ForwardStack.Clear();
     }
 
     private void ApplyTitleBarContent()

Wino.Messages/Client/Navigation/NavigateManageAccountsRequested.cs

@@ -1,6 +0,0 @@
-namespace Wino.Messaging.Client.Navigation;
-
-/// <summary>
-/// Navigates to manage accounts page.
-/// </summary>
-public record NavigateManageAccountsRequested;