From cfe572f30bb40e749ecbb84cacc9477a35aa86e3 Mon Sep 17 00:00:00 2001
From: Steven Kirk <grokys@gmail.com>
Date: Fri, 1 Jul 2022 16:56:53 +0200
Subject: [PATCH] Remove node from parent when reparented.

When a control was move from one parent container to another, and that move caused the new parent container to be laid out in a different position, a code path was taken which resulted in the `VisualNode` being present under both the old and new containers.

Ensure that the node is removed from its old parent in this case.

Fixes #7381
Fixes #6103 (probably)
---
 src/Avalonia.Base/Rendering/SceneGraph/SceneBuilder.cs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Avalonia.Base/Rendering/SceneGraph/SceneBuilder.cs b/src/Avalonia.Base/Rendering/SceneGraph/SceneBuilder.cs
index 5dc426ab06..e4d5a1ca68 100644
--- a/src/Avalonia.Base/Rendering/SceneGraph/SceneBuilder.cs
+++ b/src/Avalonia.Base/Rendering/SceneGraph/SceneBuilder.cs
@@ -158,6 +158,7 @@ namespace Avalonia.Rendering.SceneGraph
             if (result != null && result.Parent != parent)
             {
                 Deindex(scene, result);
+                ((VisualNode?)result.Parent)?.RemoveChild(result);
                 result = null;
             }