Is local undo not working for the Zone editor?

Usually we can undo a change made to part X prior to a change made to part Y by opening the editor of X and undo.
Below an example from Cubase 6.

However this behavior does not work for the file menu (Edit > Undo [action]) anymore when the traditional separate editor is open, nor does it work for the Zone editor.
Is that expected behavior (video: Cubase 9.5.0 Local undo not working on Zone Editor - YouTube)?

It works for me when editing using a separate window, but not the lower zone.

So you can use the file menu (Edit > Undo [action]) to show the last action for that particular part when opened in the separate editor too?

I can reproduce the same already with Cubase 8.5 too. I didn’t test older Cubase versions. The History is content related.

Thanks. So it’s actually a regression compared to how it was with versions prior to 8!?
I hope they will fix this because local undo is super powerful, even for the zone editor.

I would say the content of the Lower Zone is the Project window, actually.

I’m not sure I follow. When I’m focused on the Arrangement and choose Edit > Select > All (CTRL+A), all the items in the Arrangement are selected. When I do the same with focus on the Lower Zone Editor, all the items in the Lower Zone Editor are selected. Same goes for other command like e.g. Mute, Move to cursor, Cut etc. So in those cases the Lower Zone Editor and Arrangement are independent, just like the Arrangement and the Separate Editor.
However the Lower Zone Editor and the Arrangement share the same undo buffer, like the In Place Editor. Since the In Place Editor also shares the same edit functions as the Arrangement, that one makes sense. For the Lower Zone Editor however it doesn’t make sense because it’s independent in anything else (unless linked).

Yes, exactly. I would say it’s the same as the In Place Editor. It shared the same edit functions.

But that’s the thing, the In Place Editor follows all the edit KC’s of the Arrangement and is also included in the undo buffer of the Arrangement, that makes sense. The Lower Zone Editor however follows all the commands of the Separated editor, except the undo buffer of the Separate editor. Instead it uses the undo of the Arrangement. It doesn’t make sense.