Rated 3 out of 5 stars
This add-on is necessary, but it misses important features. Assuming somebody has many folders, finds > 2000 duplicates, a way to select specific folders to keep the e-mails from is needed. First or last copies doesn't help as the folders are not listed in a ordered fashion, so in one duplicate item folder A comes first, then B, but in other duplicate item folder B comes first, then A. Selecting a range to change the choice does not work either. It's a pain to take them one by one.