Every action, which you make in Cubetto Toolset or the Model Editor, is done within a transaction. A transaction contains several steps that are necessary for the execution of the action. If a transaction is cancelled, e.g. by pressing the Cancel button, all steps or -in other words- work levels will be undone and the status of before the action will be restored.
As transactions can be cascading, cancelling the superior transaction amounts to cancelling automatically all subordinate transactions, even if these transactions were completed. You can follow this effect by editing an element with the Object Editor in the Model Editor and open another editor within the Object Editor. Make changes here and confirm them by pressing the OK button, but end the first dialog by pressing the Cancel button. Thus all changes will be undone, including the actions confirmed in the second dialog.
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