This is the best

I enjoy all the features this app offers, but I gave it a three out of five because it slows my browser considerably. Most especially, it freezes completely in G. Docs.

Re-installed but unfortunately didn't still work

firefox add-on login doesn't work!!!

It asks me to login but never lets me login.

Does not work... It says "Grammarly is active, but key features are missing" I cleared cookies, all datas, re-installed plugin, ... always same with macOS 11.0.1 - Firefox 84.0.2, That's really annoying for this such a cool thing.