Rated 3 out of 5 stars

Personal i like
addons.mozilla.org/en-US/firefox/addon/gmail-watcher/?src=search
than
https://addons.mozilla.org/en-US/firefox/addon/gmail-notifier-restartless/?src=search
.
Because sound of gmail-notifier-restartless too small . Hope next version better

This review is for a previous version of the add-on (0.2.3.1-signed).