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I would like to be able to have more undos available. Is there a way to do this?
The Undo and Redo commands allow you to undo the last action performed, as well redo actions that were recently Undone. Actions that can be Undone and Redone include creating, editing and deleting objects.
By default, the ten most recent actions can be Undone and Redone. If you would like to increase or decrease this number, you can do so in the Preferences dialog.
Increasing the number of undos may substantially increase the hard drive space used on your computer, and can have a noticeable effect on performance when working on larger plans.