use disposable pattern to make logic more robust.

src/Avalonia.Controls/Window.cs

@@ -567,10 +567,8 @@ namespace Avalonia.Controls
         /// </summary>
         public override void Hide()
         {
-            try
+            using (FreezeVisibilityChangeHandling())
             {
-                IgnoreVisibilityChange = true;
-                
                 if (!_shown)
                 {
                     return;
@@ -596,10 +594,6 @@ namespace Avalonia.Controls
                 IsVisible = false;
                 _shown = false;
             }
-            finally
-            {
-                IgnoreVisibilityChange = false;
-            }
         }
 
         /// <summary>
@@ -615,7 +609,7 @@ namespace Avalonia.Controls
 
         protected override void IsVisibleChanged(AvaloniaPropertyChangedEventArgs e)
         {
-            if (!IgnoreVisibilityChange)
+            if (!IgnoreVisibilityChanges)
             {
                 var isVisible = e.GetNewValue<bool>();
 
@@ -685,12 +679,10 @@ namespace Avalonia.Controls
 
         private void ShowCore(Window? owner)
         {
-            try
+            using (FreezeVisibilityChangeHandling())
             {
-                IgnoreVisibilityChange = true;
-
                 EnsureStateBeforeShow();
-                
+
                 if (owner != null)
                 {
                     EnsureParentStateBeforeShow(owner);
@@ -733,10 +725,6 @@ namespace Avalonia.Controls
                 Renderer?.Start();
                 OnOpened(EventArgs.Empty);
             }
-            finally
-            {
-                IgnoreVisibilityChange = false;
-            }
         }
 
         /// <summary>
@@ -766,19 +754,17 @@ namespace Avalonia.Controls
         /// </returns>
         public Task<TResult> ShowDialog<TResult>(Window owner)
         {
-            try
+            using (FreezeVisibilityChangeHandling())
             {
-                IgnoreVisibilityChange = true;
-                
                 EnsureStateBeforeShow();
-                
+
                 if (owner == null)
                 {
                     throw new ArgumentNullException(nameof(owner));
                 }
-                
+
                 EnsureParentStateBeforeShow(owner);
-                
+
                 if (_shown)
                 {
                     throw new InvalidOperationException("The window is already being shown.");
@@ -828,10 +814,6 @@ namespace Avalonia.Controls
                 OnOpened(EventArgs.Empty);
                 return result.Task;
             }
-            finally
-            {
-                IgnoreVisibilityChange = false;
-            }
         }
 
         private void UpdateEnabled()

src/Avalonia.Controls/WindowBase.cs

@@ -42,9 +42,11 @@ namespace Avalonia.Controls
 
         private bool _hasExecutedInitialLayoutPass;
         private bool _isActive;
-        protected bool IgnoreVisibilityChange { get; set; }
+        private int _ignoreVisibilityChanges;
         private WindowBase? _owner;
 
+        protected bool IgnoreVisibilityChanges => _ignoreVisibilityChanges > 0; 
+
         static WindowBase()
         {
             IsVisibleProperty.OverrideDefaultValue<WindowBase>(false);
@@ -66,6 +68,11 @@ namespace Avalonia.Controls
             impl.PositionChanged = HandlePositionChanged;
         }
 
+        protected IDisposable FreezeVisibilityChangeHandling()
+        {
+            return new IgnoreVisibilityChangesDisposable(this);
+        }
+
         /// <summary>
         /// Fired when the window is activated.
         /// </summary>
@@ -125,18 +132,12 @@ namespace Avalonia.Controls
         /// </summary>
         public virtual void Hide()
         {
-            IgnoreVisibilityChange = true;
-
-            try
+            using (FreezeVisibilityChangeHandling())
             {
                 Renderer?.Stop();
                 PlatformImpl?.Hide();
                 IsVisible = false;
             }
-            finally
-            {
-                IgnoreVisibilityChange = false;
-            }
         }
 
         /// <summary>
@@ -144,9 +145,7 @@ namespace Avalonia.Controls
         /// </summary>
         public virtual void Show()
         {
-            IgnoreVisibilityChange = true;
-
-            try
+            using (FreezeVisibilityChangeHandling())
             {
                 EnsureInitialized();
                 ApplyStyling();
@@ -157,14 +156,11 @@ namespace Avalonia.Controls
                     LayoutManager.ExecuteInitialLayoutPass();
                     _hasExecutedInitialLayoutPass = true;
                 }
+
                 PlatformImpl?.Show(true, false);
                 Renderer?.Start();
                 OnOpened(EventArgs.Empty);
             }
-            finally
-            {
-                IgnoreVisibilityChange = false;
-            }
         }
 
         /// <summary>
@@ -202,23 +198,17 @@ namespace Avalonia.Controls
 
         protected override void HandleClosed()
         {
-            IgnoreVisibilityChange = true;
-
-            try
+            using (FreezeVisibilityChangeHandling())
             {
                 IsVisible = false;
-                
+
                 if (this is IFocusScope scope)
                 {
                     FocusManager.Instance?.RemoveFocusScope(scope);
                 }
-                
+
                 base.HandleClosed();
             }
-            finally
-            {
-                IgnoreVisibilityChange = false;
-            }
         }
 
         /// <summary>
@@ -320,7 +310,7 @@ namespace Avalonia.Controls
 
         protected virtual void IsVisibleChanged(AvaloniaPropertyChangedEventArgs e)
         {
-            if (!IgnoreVisibilityChange)
+            if (_ignoreVisibilityChanges == 0)
             {
                 if ((bool)e.NewValue!)
                 {
@@ -332,5 +322,21 @@ namespace Avalonia.Controls
                 }
             }
         }
+        
+        private readonly struct IgnoreVisibilityChangesDisposable : IDisposable
+        {
+            private readonly WindowBase _windowBase;
+
+            public IgnoreVisibilityChangesDisposable(WindowBase windowBase)
+            {
+                _windowBase = windowBase;
+                _windowBase._ignoreVisibilityChanges++;
+            }
+            
+            public void Dispose()
+            {
+                _windowBase._ignoreVisibilityChanges--;
+            }
+        }
     }
 }