Rated 5 out of 5 stars

per Alexander FX el feb. 9, 2010 · enllaç permanent

Exactly what I need. Does exactly what it says, and does it almost perfectly (I use it on Thunderbird 2.0.23). What more can I say?
Defects?
If it could prevent the Thunderbird window from appearing at all, it would reach Nirvana (but that seems absolutely impossible to achieve). Also, the "Inform on New Mail" should be documented a bit more, but it's easy enough to figure out.
In any case, five stars without question.