Review for New Mail Attention by soulrebelno1
Rated 5 out of 5 stars
This new mail Add-on actually works and is the only one that does 100% of the time, and that includes Thunderbird's own notifications have never worked properly. It would be an even better add-on if it had pop-up and sound options, here's hoping.
To create your own collections, you must have a Mozilla Add-ons account.