diff --git a/Wino.Core.WinUI/Interfaces/IWinoShellWindow.cs b/Wino.Core.WinUI/Interfaces/IWinoShellWindow.cs
index 67c07694..e124ebe1 100644
--- a/Wino.Core.WinUI/Interfaces/IWinoShellWindow.cs
+++ b/Wino.Core.WinUI/Interfaces/IWinoShellWindow.cs
@@ -1,9 +1,11 @@
-using Microsoft.UI.Xaml;
+using CommunityToolkit.Mvvm.Messaging;
+using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Controls;
+using Wino.Messaging.UI;
 
 namespace Wino.Core.WinUI.Interfaces;
 
-public interface IWinoShellWindow
+public interface IWinoShellWindow : IRecipient<TitleBarShellContentUpdated>
 {
     void HandleAppActivation(LaunchActivatedEventArgs args);
     TitleBar GetTitleBar();
diff --git a/Wino.Mail.WinUI/AppShell.xaml.cs b/Wino.Mail.WinUI/AppShell.xaml.cs
index db0a259c..621854f7 100644
--- a/Wino.Mail.WinUI/AppShell.xaml.cs
+++ b/Wino.Mail.WinUI/AppShell.xaml.cs
@@ -17,6 +17,7 @@ using Wino.Core.Domain.Interfaces;
 using Wino.Core.Domain.Models.Folders;
 using Wino.Core.Domain.Models.MailItem;
 using Wino.Core.Domain.Models.Navigation;
+using Wino.Core.WinUI;
 using Wino.Core.WinUI.Controls;
 using Wino.Extensions;
 using Wino.Mail.ViewModels.Data;
@@ -25,6 +26,7 @@ using Wino.MenuFlyouts.Context;
 using Wino.Messaging.Client.Accounts;
 using Wino.Messaging.Client.Mails;
 using Wino.Messaging.Client.Shell;
+using Wino.Messaging.UI;
 using Wino.Views.Abstract;
 
 namespace Wino.Views;
@@ -35,10 +37,14 @@ public sealed partial class AppShell : AppShellAbstract,
     IRecipient<CreateNewMailWithMultipleAccountsRequested>,
     IRecipient<InfoBarMessageRequested>
 {
+    [GeneratedDependencyProperty]
+    public partial UIElement TopShellContent { get; set; }
+
     public AppShell() : base()
     {
         InitializeComponent();
     }
+    public Frame GetShellFrame() => ShellFrame;
 
     private async void ItemDroppedOnFolder(object sender, DragEventArgs e)
     {
@@ -212,18 +218,9 @@ public sealed partial class AppShell : AppShellAbstract,
         }
     }
 
-    private void ShellFrameContentNavigated(object sender, Microsoft.UI.Xaml.Navigation.NavigationEventArgs e)
-    {
-        // => RealAppBar.ShellFrameContent = (e.Content as BasePage).ShellContent;
+    private void ShellFrameContentNavigated(object sender, Microsoft.UI.Xaml.Navigation.NavigationEventArgs e) => TopShellContent = ((BasePage)e.Content).ShellContent;
 
-        // TODO: WinUI3: Update shell content. Just remove it.
-    }
-
-    private void BackButtonClicked(WinoAppTitleBar sender, RoutedEventArgs args)
-    {
-        WeakReferenceMessenger.Default.Send(new ClearMailSelectionsRequested());
-        WeakReferenceMessenger.Default.Send(new DisposeRenderingFrameRequested());
-    }
+    partial void OnTopShellContentChanged(UIElement newValue) => WeakReferenceMessenger.Default.Send(new TitleBarShellContentUpdated());
 
     private async void MenuItemContextRequested(UIElement sender, ContextRequestedEventArgs args)
     {
diff --git a/Wino.Mail.WinUI/ShellWindow.xaml b/Wino.Mail.WinUI/ShellWindow.xaml
index 0302fd25..5cdb6a86 100644
--- a/Wino.Mail.WinUI/ShellWindow.xaml
+++ b/Wino.Mail.WinUI/ShellWindow.xaml
@@ -21,6 +21,8 @@
         <TitleBar
             x:Name="ShellTitleBar"
             Title="{x:Bind StatePersistanceService.CoreWindowTitle, Mode=OneWay}"
+            HorizontalContentAlignment="Stretch"
+            VerticalContentAlignment="Stretch"
             BackRequested="BackButtonClicked"
             IsBackButtonVisible="{x:Bind StatePersistanceService.IsBackButtonVisible, Mode=OneWay}"
             IsPaneToggleButtonVisible="True"
diff --git a/Wino.Mail.WinUI/ShellWindow.xaml.cs b/Wino.Mail.WinUI/ShellWindow.xaml.cs
index 2bde3953..c188fcb0 100644
--- a/Wino.Mail.WinUI/ShellWindow.xaml.cs
+++ b/Wino.Mail.WinUI/ShellWindow.xaml.cs
@@ -7,6 +7,7 @@ using Wino.Core.Domain.Interfaces;
 using Wino.Core.WinUI;
 using Wino.Core.WinUI.Interfaces;
 using Wino.Messaging.Client.Mails;
+using Wino.Messaging.UI;
 using Wino.Views;
 using WinUIEx;
 
@@ -19,6 +20,8 @@ public sealed partial class ShellWindow : WindowEx, IWinoShellWindow
 
     public ShellWindow()
     {
+        WeakReferenceMessenger.Default.Register<TitleBarShellContentUpdated>(this);
+
         InitializeComponent();
 
         MinWidth = 420;
@@ -56,4 +59,12 @@ public sealed partial class ShellWindow : WindowEx, IWinoShellWindow
     {
         PreferencesService.IsNavigationPaneOpened = !PreferencesService.IsNavigationPaneOpened;
     }
+
+    public void Receive(TitleBarShellContentUpdated message)
+    {
+        if (MainShellFrame.Content is AppShell shellPage)
+        {
+            ShellTitleBar.Content = shellPage.TopShellContent;
+        }
+    }
 }
diff --git a/Wino.Mail.WinUI/Views/MailListPage.xaml b/Wino.Mail.WinUI/Views/MailListPage.xaml
index 96327cbb..dab1109a 100644
--- a/Wino.Mail.WinUI/Views/MailListPage.xaml
+++ b/Wino.Mail.WinUI/Views/MailListPage.xaml
@@ -209,7 +209,7 @@
         <KeyboardAccelerator Key="Delete" Invoked="DeleteAllInvoked" />
     </Page.KeyboardAccelerators>
     <wino:BasePage.ShellContent>
-        <Grid>
+        <Grid HorizontalAlignment="Stretch" Background="Red">
             <!--  Hidden focus receiver...  -->
             <TextBox
                 Grid.Column="1"
diff --git a/Wino.Messages/UI/TitleBarShellContentUpdated.cs b/Wino.Messages/UI/TitleBarShellContentUpdated.cs
new file mode 100644
index 00000000..40ac2d80
--- /dev/null
+++ b/Wino.Messages/UI/TitleBarShellContentUpdated.cs
@@ -0,0 +1,3 @@
+namespace Wino.Messaging.UI;
+
+public record TitleBarShellContentUpdated;