Editing : Editing Basics : Multiple Undo

Multiple Undo
For more information, see the following topics:
Pro Tools can keep track of up to 32 of the last undoable operations, allowing you to return to a previous editing state.
The Undo operations in Pro Tools are stored in a queue, in the order in which they were invoked. When choosing Edit > Undo, the most recent operation is undone. If you choose Undo again, the next operation in the queue is undone. You can also choose Edit > Redo to redo an operation, which moves back through the Undo queue by one step.
When the number of operations in the Undo queue reaches the maximum specified level of Undo (set in the Editing Preferences page), performing another undoable operation will remove the oldest operation at the top of the queue.
To undo the last operation, do one of the following:
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Choose Edit > Undo.
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To redo the last undone operation, do one of the following:
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Choose Edit > Redo.
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