diff --git a/cura/Settings/SettingInheritanceManager.py b/cura/Settings/SettingInheritanceManager.py
index 2f81526813..49cf5c7c83 100644
--- a/cura/Settings/SettingInheritanceManager.py
+++ b/cura/Settings/SettingInheritanceManager.py
@@ -109,8 +109,11 @@ class SettingInheritanceManager(QObject):
                 self._settings_with_inheritance_warning.remove(key)
                 settings_with_inheritance_warning_changed = True
 
-            # Find the topmost parent (Assumed to be a category)
             parent = definitions[0].parent
+            if parent is None:
+                return
+            
+            # Find the topmost parent (Assumed to be a category)
             while parent.parent is not None:
                 parent = parent.parent