Assegnate 4 su 5 stelle

Like it so far, some visual feedback would be nice
especially an column in the message list showing which (if any) folder is associated with this sender. Possibly an UI so you can inspect and maybe edit/delete associations.

Questa recensione riguarda una versione precedente (0.3) del componente aggiuntivo. 

The SQLite Manager (https://addons.mozilla.org/en-US/firefox/addon/5817/) does exactly what you want.