1. In my opinion, it's very problematic that the actions in the Undo button
disappear each time an Auto-save is performed. Auto-save is involuntary, as
opposed to a Save action the user performs. I also must add that I didn't
notice this phenomenon happen in other Office applications.
2. Also, there should be a way of setting the number of Undo actions Excel
should keep, with an option of saving an "endless" number of actions. If my
computer can't handle it, I wouldn't mind if at some point a task pane will
appear, informing me that the system free resources are getting low and
allowing me to delete some of the Undo actions that were saved.
3. Furthermore, suppose that I'm in the middle of working on an Office file
while suddenly I have to go. Wouldn't it be nice if I could save an Office
file together with its Undo actions?

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