Rated 5 out of 5 stars

Featuring:
- Easily accessible UI (not only via the addons window "Preferences" button but also via the Tools menu
- Makes life easier for all other addons
- Dedicated help forum with responsive extension maintainer.

I made it a point to install it in all three of Firefox, Thunderbird and SeaMonkey.

This review is for a previous version of the add-on (5.3.2.3).