Review for Duplicate Contact Manager by John Pang
Rated 1 out of 5 stars
Work well when need to sort out the address book. But once you sort out the address book, need to disable it. It has problem on Thunderbird 2.0.0.19 with Mac OS 10.5.6 (or even older).
Problem will cause Thunderbird unstable, search function not working (broken UI) and then search window does not appears and you must force quit thunderbird.
To create your own collections, you must have a Mozilla Add-ons account.