You can audition various versions of undos and redos by clicking the Play button next to each entry. However, some Undo or Redo operations cannot be auditioned.
To undo or redo an operation, double-click the operation in the Undo or Redo list. If you undo or redo an operation that is not at the top of the list, all operations that were performed after that operation will also be undone (this can take some time when working on large files).
From the Edit menu, choose Clear Undo/Redo History (or right-click the Undo/Redo History window and choose Clear from the shortcut menu) to erase the temporary undo files for the active file.
These files take up disk space, so you might want to clear them periodically when you are sure that you don’t want to undo any of your previous changes. This function affects only the current sound file.
The Undo/Redo History Window
From the View menu, choose Undo/Redo History to open or close the Undo/Redo History window. This window allows you to see all of your edit operations. The most recently performed operations are displayed at the top of each list.
When you perform an edit operation on your sound file, such as cutting data, the operation name appears at the top of the Undo list. When you undo the cut, the operation disappears from the Undo list and appears in the Redo list.
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