Review for Duplicate Contact Manager by Anders Ringnér
Rated 4 out of 5 stars
A good addon! For future development: keyboard shortcuts would be valuable during the deduping process (e.g. Alt-1 or Alt-2 for choosing which contact to save).
This review is for a previous version of the add-on (0.8.1).To create your own collections, you must have a Mozilla Add-ons account.