Groups with all files marked is a great feature & a great advantage over other duplicate file finders.
How about making it (both) a bit more transparent, & also much more obvious .
Like (I suppose) it "knows" when there are groups with all files marked, or not. So when not, leave the button grayed out. No need to check in there, because we already know there is nothing to be found. And when there are some groups with all files marked - make it stand out, jump in your face, & say, "hey, beware, you have some groups with all files marked!".
Similar problem, very cumbersome (rather impossible) to manually locate Groups with all files marked for deletion. Suggest that such Groups are shown in a separate pop-up window, where the user can take corrective action (Unmark files manually). Otherwise, a great piece of software.
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