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#9Wizard: Back-Button returns to dialog that is finished and should not be returned to

The wizard does not prevent to use the back-button to go back to a dialog that was already finished.

Example: 1) In the dashboard, click "remove" in a repository. 2) Click "Do it!" in order to confirm removal. 3) After automatic return to dashboard, click back-button (arrow-to-left in the upper-left corner) 4) You can againt click "Do it!" -> what happens? No error or warning message is displayed.