Puntuado con 3 de 5 estrellas

It says it works with Message Filters, but when i choose the 'Mailbox Alert', it is BLANK on the right side, so you cannot choose the alert.

Esta valoración es de una versión anterior del complemento (0.23.1). 

Yeah, that was (I hope) the last thing that broke with the big Thunderbird changes, and the hardest one to get working again. I finally found a way to fix it, and it should now work with version 0.24.