From 5f57b0f314509bdf59774ce23a332057d88b5e18 Mon Sep 17 00:00:00 2001
From: Markus Lampert <markus@bibi.ca>
Date: Mon, 28 Dec 2020 19:43:11 -0800
Subject: [PATCH] Remove event registration when task panel is destroyed.

---
 src/Mod/Path/PathScripts/PathOpGui.py | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/Mod/Path/PathScripts/PathOpGui.py b/src/Mod/Path/PathScripts/PathOpGui.py
index d0d5c22d83..dd589c9c85 100644
--- a/src/Mod/Path/PathScripts/PathOpGui.py
+++ b/src/Mod/Path/PathScripts/PathOpGui.py
@@ -212,9 +212,12 @@ class TaskPanelPage(object):
         self.parent = None
         self.panelTitle = 'Operation'
 
-        if hasattr(self.form, 'toolController'):
+        if self._installTCUpdate():
             PathJob.Notification.updateTC.connect(self.resetToolController)
 
+    def _installTCUpdate(self):
+        return hasattr(self.form, 'toolController')
+
     def setParent(self, parent):
         '''setParent() ... used to transfer parent object link to child class.
         Do not overwrite.'''
@@ -250,6 +253,8 @@ class TaskPanelPage(object):
     def pageCleanup(self):
         '''pageCleanup() ... internal callback.
         Do not overwrite, implement cleanupPage(obj) instead.'''
+        if self._installTCUpdate():
+            PathJob.Notification.updateTC.disconnect(self.resetToolController)
         self.cleanupPage(self.obj)
 
     def pageRegisterSignalHandlers(self):