With the new architecture, it is possible to provide a global undo mechanism.

Since the execution of any Command is surrounded by the events beforeExecute and afterExecute, a simple Plugin will do the job:

The Plugin manages an undo and a redo stack to store the Commands. If it encounters a Command, that is not a RecoverableCommand, the undo stack is cleared.

In order to perform an Undo or a Redo, two Commands are needed: