Rated 3 out of 5 stars
Not showing new e-mails, but there are some mail in the account, and the mail icon is greyed out lot of times during the day it cannot check for new mails.
I have issues with a few extension since FF51 came out, secure login, https everywhere and Gmail Manager-community. I do not know what's going on, but I hope someone will solve this.
RED Mail icon Tool tip shows
(null) important unread message(s).