From 7dadacd0eaf91f2a768da2b9996f62320d4b093e Mon Sep 17 00:00:00 2001
From: Nikita Tsukanov <keks9n@gmail.com>
Date: Tue, 31 Mar 2020 21:31:10 +0300
Subject: [PATCH] [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 5da9021677..a2d48b9689 100644
--- a/src/Avalonia.X11/X11Window.cs
+++ b/src/Avalonia.X11/X11Window.cs
@@ -694,7 +694,15 @@ 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()