If you’re running this with BBEdit 12, the Unminify command will leave a copy of the minified text at the top of the file.
That’s because BBEdit has the Copy menu command enabled even without a selection (for some reason).
So the fix is to drag the Action to type Command-A out of the test for an enabled Copy menu item and disable the test action.
I’d fix that here but I have to think a future BBEdit revision will address this issue. It isn’t an issue with the latest TextWrangler.