From 4e5cec2d9e933f56be489ccc5ba5cf6706ff86aa Mon Sep 17 00:00:00 2001
From: danwalmsley <dan@walms.co.uk>
Date: Fri, 3 Apr 2020 09:46:44 -0300
Subject: [PATCH] Merge pull request #3712 from
 AvaloniaUI/x11-remove-transient-hint

[X11, FlyWM] Completely remove WM_TRANSIENT_FOR property
---
 src/Avalonia.X11/X11Window.cs | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/Avalonia.X11/X11Window.cs b/src/Avalonia.X11/X11Window.cs
index 94d4003e1c..74a7a33be6 100644
--- a/src/Avalonia.X11/X11Window.cs
+++ b/src/Avalonia.X11/X11Window.cs
@@ -735,7 +735,15 @@ namespace Avalonia.X11
             _transientParent = window;
             _transientParent?._transientChildren.Add(this);
             if (informServer)
-                XSetTransientForHint(_x11.Display, _handle, _transientParent?._handle ?? IntPtr.Zero);
+                SetTransientForHint(_transientParent?._handle);
+        }
+
+        void SetTransientForHint(IntPtr? parent)
+        {
+            if (parent == null || parent == IntPtr.Zero)
+                XDeleteProperty(_x11.Display, _handle, _x11.Atoms.XA_WM_TRANSIENT_FOR);
+            else
+                XSetTransientForHint(_x11.Display, _handle, parent.Value);
         }
 
         public void Show()