Ability to UNDO last change in Multi-User editing mode

In the new Multi-User Editing mode it would be great to be able to UNDO the last change you did in case you make an error. E.g. if you accidentally have all speakers selected for a large many room project and then hit delete and you lose all the speakers for all rooms, when you may have only wanted to delete the one speaker in one room. In the NON Multi-User mode if this happens you can just not hit save, but in the Multi-User mode anything you do is automatically saved and cannot be undone. Otherwise the Multi-User mode is a fantastic enhancement!