But how would that work with the mouse over event? I.e. I can’t undo that a user is currently hovering over a square. The only thing I see that could be undone

But how would that work with the mouse over event? I.e. I can’t undo that a user is currently hovering over a square. The only thing I see that could be undone is the clicking. Let me know if I’m missing something and how should undo work. Thanks!