Material item does not vanish when material list is changed

1. Go to the material view where one can see all the material items in the camp
2. Open one material list
3. Edit any material item and change its material list to a different one

Expected outcome: The material item should vanish from the view because it is no longer part of this list
Actual outcome: The material item remains visible in the old list until a reload is done

Possible fix: Force reload the material list and/or its material items after saving changes to a material item.