In the texture panel, when you click something it brings up the whole texture editor. Clicking save brings you back to the texture panel. But what if I don't want to save the changes I made? Where's "cancel" or "back"?
This is a feature that is used extremely rarely in any workflow and is not trivial/straightforward to implement and maintain everywhere, so it got scrapped from the very beginning because of its workload-slash-usefulnes ratio.