PCS

Undo

Stack size

Lets you indicate the number of commands (from 0 to 99) of global actions (object edition or completed command) which can be undone for each document.

Whatever the value, it is always possible to undo local actions inside the current global action as any action performed during a global action is considered as a local action.
 

Check Multi-Editor Undo

If this option is selected, it means that you prevent any unpredictable behavior in the Undo/Redo process if a document is open in several editors for modification purpose.

By default, this option is selected.