This is happenoing on all of my 4 PC's, I have 6 Gmail accounts, and on one only one signs in, and, it is not always the sames ones that don't sign in. I have tried everything, clearing cache, I check all passowrds in FF password manager to make sure they were correct. I even created a new profile and the same issue. I can't believe I am the only one having this issue, this is happening on 4 different PC's. My emails login fine on my Android devices with no issues. I am able also to login to all of my accounts manually, so I know it is not a Gmail issue.
I have 3 Gmail accounts and, up until a couple of days ago, have had no problems. However, for no apparent reason, only 2 of the 3 accounts are being checked.
I havetried everything, deleting the affected account and adding it back...doing the same thing with all 3 accounts...removing the Add-on and re-installing it. Nothing works.
There's nothing that can be done right now, 2 step just does not work with xnotifier for hotmail. Using main password, using app password, even using ms security code, nothing works, 2 step pop up comes up over and over and over from xnotifier.
