Rated 5 out of 5 stars

Absolutely brilliant. This achieved in seconds what it used to took me days to do manually (sorting invalid e-mails out of a club mailing list).
Unfortunately it does not work in TB 3.0 (yet) so I'm thinking of going back to thunderbird 2.

This review is for a previous version of the add-on (1.2). 

Now Supports TB3

Sorry for the delay. Not my highest priority in life. But it is now working and offers a new TB3-specific function. Check it out!