Rated 5 out of 5 stars
The current login problem is due to poorly implemented changes by Google Gmail team - NOT the fault of this add-on's team, nor the fault of Mozilla Firefox.
Remember, these are volunteer developers that generously contribute their own time to keep this add-on working without compensation. If you are not happy with its performance you are welcome to go elsewhere or write your own Gmail extension. However, whining, and impatiently demanding a fix is rude, inconsiderate, and reflects poorly on the user. It may also discourage future development. By using free software, the developers owe you nothing. You owe them your gratitude and respect.
No one is forcing you to use this add-on. You are always welcome to try other add-ons or web browsers.
If you feel compelled to complain - go to complain to Google. I suggest Reddit however they are other sites.