I sometimes find myself having a brilliant idea and going around changing stuff in multiple layers or masters. Then I find that the idea is crap and try to roll back. Since I saved an hour or seconds ago, reverting to the file state is not an option. So I hammer the undo key and… don’t see what I’m undoing unless I happen to look at the layer that is currently being undone. The bottom undo text is often just saying "Undo: " so I have no idea what I’m doing. Switching to the layer or whatever that the current undo works on may be helpful.
Also, I suspect that undo only undoes things in the current glyph, but sometimes I’m not sure. Maybe expand the undo status text to say something like “Undoing in /whatever: some action” for clarity?
I have the same problem/request: Each time I undo actions while I’m on a master (let’s say Regular), sometimes I undo actions I’ve done on other masters (Bold/Italic) and there’s no way to know what I’m undoing unless I go check on each master.
It would be perfect if Undoing/Redoing was limited to the current Master (just like it is limited to the glyph. When a glyph is selected, hitting undo doesn’t work on other glyphs)