This piece of software was the only reason which prompted me to use Chrome some time ago. It's now available on Firefox which provides an even better user experience. Many thanks to the developper for thiswork and the Mozilla team for ongoing efforts necessary to facilitate the port from Chrome to Firefox. Best addon ever for me!

The only reason I was using the other browser was because of this awesome Add-ons and sadly it wasn't available on Firefox, but now I can finally use Firefox as my main browser and get to use Checker Plus for Gmail \o/ WebExtensions FTW! I love how I can do everything in one place and get notified whenever I received an email and the best part is having a unified inbox at glance! 5 stars is not enough TBH. Thanks!