[Windows] - Fixed Window Title Not Shown When Reverting from TitleBar to Default State (#27148)

* Fixed-Window-Title-Issue

* Modified-code

Author: prakashKannanSf3972

src/Core/src/Platform/Windows/WindowRootView.cs

@@ -450,6 +450,7 @@ internal void SetTitleBar(ITitleBar? titlebar, IMauiContext? mauiContext)
 				if (AppTitleBarContentControl is not null)
 				{
 					AppTitleBarContentControl.Content = null;
+					UpdateAppTitleBarTemplate();
 				}
 				return;
 			}
@@ -562,6 +563,17 @@ private void SetTitleBarInputElements()
 			PassthroughTitlebarElements = passthroughElements;
 		}
 
+		void UpdateAppTitleBarTemplate()
+		{
+			// Ensure the default Window Title template is reapplied when switching from a TitleBar.
+			// The ContentTemplateSelector is reset to the default when ContentTemplate is null, restoring proper title display.
+			if (AppTitleBarContentControl is not null && AppTitleBarContentControl.ContentTemplateSelector is null)
+			{
+				AppTitleBarContentControl.ContentTemplateSelector =
+				(DataTemplateSelector)Application.Current.Resources["MauiAppTitleBarTemplateSelector"];
+			}
+		}
+
 		static void OnAppTitleBarTemplateChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
 		{
 			((WindowRootView)d)._appTitleBar = null;