CQ: Fix possible error when loading TitleBar property

Author: XTorLukas

src/Files.App/UserControls/TabBar/TabBar.xaml.cs

@@ -76,12 +76,7 @@ public TabBar()
 			tabHoverTimer.Interval = TimeSpan.FromMilliseconds(Constants.DragAndDrop.HoverToOpenTimespan);
 			tabHoverTimer.Tick += TabHoverSelected;
 
-			var appWindow = MainWindow.Instance.AppWindow;
-
-			TitleBarWidth =
-				new(FilePropertiesHelpers.FlowDirectionSettingIsRightToLeft
-					? appWindow.TitleBar.LeftInset
-					: appWindow.TitleBar.RightInset);
+			InitializeTitleBarAsync();
 
 			AppearanceSettingsService.PropertyChanged += (s, e) =>
 			{
@@ -94,6 +89,40 @@ public TabBar()
 			};
 		}
 
+		/// <summary>
+		/// Initializes the title bar asynchronously. This method attempts to get the title bar's left and right insets.
+		/// If the values are properly initialized, it sets the <see cref="TitleBarWidth"/> property. If the initialization fails,
+		/// it falls back to a default width.
+		/// </summary>
+		private async void InitializeTitleBarAsync()
+		{
+			const int maxAttempts = 10; // Maximum number of attempts (1 second total wait)
+			const int delayInterval = 100; // Delay interval in milliseconds
+			const double defaultWidth = 138; // Default width if initialization fails
+
+			var appWindow = MainWindow.Instance.AppWindow;
+
+			for (int attempt = 0; attempt < maxAttempts; attempt++)
+			{
+				// If TitleBar values are properly initialized, set TitleBarWidth
+				if (appWindow?.TitleBar.LeftInset != appWindow?.TitleBar.RightInset)
+				{
+					TitleBarWidth = new GridLength(
+						FilePropertiesHelpers.FlowDirectionSettingIsRightToLeft
+						? appWindow!.TitleBar.LeftInset
+						: appWindow!.TitleBar.RightInset
+					);
+					return;
+				}
+
+				// Wait for the next attempt
+				await Task.Delay(delayInterval);
+			}
+
+			// Fallback to default width if initialization fails
+			TitleBarWidth = new GridLength(defaultWidth);
+		}
+
 		private void TabView_TabItemsChanged(TabView sender, Windows.Foundation.Collections.IVectorChangedEventArgs args)
 		{
 			if (args.CollectionChange == Windows.Foundation.Collections.CollectionChange.ItemRemoved)