Review for FolderFlags by sremick
Rated 5 out of 5 stars
Perfect! This extension was exactly what I was looking for. I use subfolders beneath the Junk Mail folder and Thunderbird kept moving messages from the subfolders into the top-level junk folder because it was re-flagging them as spam. This put a stop to that.
This review is for a previous version of the add-on (1.1).To create your own collections, you must have a Mozilla Add-ons account.