Rated 5 out of 5 stars

Definitely deserves 5 out of 5 stars. A very useful extension indeed! I use it to keep track of emails which I need to reference in OneNote.
Note the new version 0.5 (you have to click "all versions" below to see it) has been updated to work with Thunderbird 5. This is my favourite thunderbird extension.

This review is for a previous version of the add-on (0.04).  This user has a previous review of this add-on.