From ba85c011059691c434532289e9c9d46542a865ad Mon Sep 17 00:00:00 2001
From: Takoooooo <tako0qq@gmail.com>
Date: Mon, 17 Jan 2022 16:09:09 +0200
Subject: [PATCH] fix

---
 src/Avalonia.Controls/Platform/DefaultMenuInteractionHandler.cs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Avalonia.Controls/Platform/DefaultMenuInteractionHandler.cs b/src/Avalonia.Controls/Platform/DefaultMenuInteractionHandler.cs
index a2bdcd1ea8..18348571bf 100644
--- a/src/Avalonia.Controls/Platform/DefaultMenuInteractionHandler.cs
+++ b/src/Avalonia.Controls/Platform/DefaultMenuInteractionHandler.cs
@@ -101,7 +101,7 @@ namespace Avalonia.Controls.Platform
                 root.Deactivated -= WindowDeactivated;
             }
             
-            if (_root is TopLevel tl)
+            if (_root is TopLevel tl && tl.PlatformImpl != null)
                 tl.PlatformImpl.LostFocus -= TopLevelLostPlatformFocus;
 
             _inputManagerSubscription?.Dispose();