Review for QuickFolders (Tabbed Folders) by Tony Mechelynck
Rated 5 out of 5 stars
Not only this is a great add-on to enhance the mail windows, its author is actively maintaining it for both Thunderbird and SeaMonkey, diligently reading bug reports and fixing problems found by users of both mailers on all three of Windows, Linux and Mac, and on 32- and 64-bit processors. :-) :-) :-)
This review is for a previous version of the add-on (3.10).To create your own collections, you must have a Mozilla Add-ons account.