Welcome to Firefox for Android Add-ons.
Add extra features and styles to make Firefox for Android your own.
CloseReview for Duplicate Contact Manager by Gavrahil
Rated 3 out of 5 stars
Very good Add-On. Does what it advertises, but has a few faults nonetheless.
Sometimes you have to manually correct some items, but much more importantly I agree with John Pang: as soon as you're done with the duplicates turn it off, or you'll have no joy with your Thunderbird GUI.
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