- How to do it: from the Menu, choose Edit/Undo or Edit/Redo.
- there are at most 10 steps in the Undo/Redo history; the history is a FIFO list (first in first out) meaning that the oldest entry will be discarded to make room for a new one;
- only these types of actions can be reverted or redone using Undo/Redo:
- the menu item Undo turns to Can’t undo if no revertible action has ever been performed in the current project;
- the menu item Redo turns to Can’t redo if Undo was never clicked, or a revertible action has been performed since the last undo;
- the Undo/Redo history is really a list of snapshots. Full snapshots of the Project Hierarchy are maintained. All revertible actions trigger a snapshot after they are performed, and one snapshot is automatically taken when the Project is loaded or created: this way, the current state of affairs is always stored as a snapshot in the Undo/Redo history — referred to as the current snapshot;
- when available, Undo and Redo also include a snapshot name and timestamp, e.g.: Undo (to voice deletion @22:12:57). The exact snapshot used depends on the menu item and is relative to the current snapshot position: Undo shows the previous snapshot while Redo shows the next;
- timestamps can be of help when the same action has been carried out several times (ex., changing a Note pitch twice in a row).