From b540e734f94fece91f2ddef8ba79325fb803764f Mon Sep 17 00:00:00 2001
From: Roy-043 <70520633+Roy-043@users.noreply.github.com>
Date: Mon, 10 Oct 2022 21:19:54 +0200
Subject: [PATCH] Arch: Improve handling of window hosts

---
 src/Mod/Arch/ArchWindow.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Mod/Arch/ArchWindow.py b/src/Mod/Arch/ArchWindow.py
index 46d3559565..3d2346a998 100644
--- a/src/Mod/Arch/ArchWindow.py
+++ b/src/Mod/Arch/ArchWindow.py
@@ -651,8 +651,8 @@ class _Window(ArchComponent.Component):
                 if hasattr(self,prop):
                     if getattr(self,prop) != getattr(obj,prop):
                         touchhosts = True
-                if touchhosts and hasattr(obj,"Hosts"):
-                    for host in obj.Hosts:
+                if touchhosts and hasattr(self, "Hosts") and hasattr(obj, "Hosts"):
+                    for host in set(self.Hosts + obj.Hosts): # use set to remove duplicates
                         # mark host to recompute so it can detect this object
                         host.touch()
             if prop in ["Width","Height","Frame"]: