Review for MessageID-Finder by John Corliss
Rated 5 out of 5 stars
This extension is one of the very few that I find indispensable when using Thunderbird. It helps me to easily find a message by using its Message-ID and it uses several methods to do so. I really wish the author would consider updating it so that it works with Thunderbird 3. In fact, its not being compatible with that version is one of the main reasons I'm not upgrading to TB3 at this point in time.
To create your own collections, you must have a Mozilla Add-ons account.