Many thanks to author. I moved on from GMailChecker https://addons.mozilla.org/en-US/firefox/addon/gmail-checker/ and want to say that CheckerPlus is a gorgeous and stunning add-on.

This was the ultimate mail checker extension on Chrome and now that I've switched to Firefox, I'm very pleased to see that it's available here, too. However it doesn't work on Firefox 53 it appears. After setting up everything as usual, the icon shows an x in the upper corner and is greyed out. I can't even open the settings anymore. I only get an endless loading icon…

Somewhy it blocks push notifications on android device.

excelente extencion para gmail, inbox. solo necesita añadir compatibilidad con outlook, hotmail.

I have just switched over from Chrome to Firefox, and to my utter delight, I found out that Checker Plus is available for Firefox as well!

This extension is a must-have extension for anyone who uses Gmail to any degree. THe extension is intuitive, the layout/UI is efficient, and it is very hard to use a browser without it once you get used to it.

Of equally great import - the developed, Jason, is a thorough professional. If you have any trouble with his extension, be sure to email him or to leave your email address when you remove the extension from your browser. He WILL get back to you promptly, and he WILL fix your problem promptly.

Wow.. as many others wrote, this extension was the only reason I had to use chrome, was missing it so much in firefox. Other addons are nowhere near to this... I am so happy it is now finally available, bye bye chrome !

I gave 3 stars, because it loses connection very often for me... Sometimes it works for hours perfectly, but often when If I click on the icon to view emails, only the Refresh/Sign In window appears :

"TypeError: can't access dead object
Refresh or try signing out/in or add account"

I have to refresh manually to see the new messages, because it still shows the outdated number of unread mails.

I dont know if others have this problem too, but thank you for this addon anyway, it is still #1 on chrome :)

Very Good! It fllow me from Chrome to Firefox. I it the best in same type plugins.

一般

Very useful

My favourite mail notification extension from google chrome! So glad it's here on firefox now too.

Great addon!!

super cool

При добавления аккаунта Mozilla не отвечает идет зависание,но если зайти в настройки mozill в плагины и добавить аккаунт отуда то зависание не происходит,также Мозилла зависает когда хочешь удолить письмо.....очень сильное зависание