Available fixed version: Gmail Manager NG Rated 3 out of 5 stars

I tracked the fixed version announced here by Mint to user ath0mas (Alexis THOMAS) at GitHub (https://github.com/ath0mas/firefox-gmail-manager-ng). It is called Gmail Manager NG. It also has a link right here: https://addons.mozilla.org/en-US/firefox/addon/gmail-manager-ng/