Grammarly is a great add on to use to fix your writting!

I have been using Grammarily for some time. It has been very useful for spelling and a lot of commas. I have rewritten some paragraphs for clarity which is also helpful. It occasionally makes verb errors with compound sentences. Sometime it wants me to change a word but it will change my meaning or emphasis. I do think it is a useful tool and have renewed my subscription.

does not work most of the time, Just not compatiable with Firefox version 87

The add-on keeps requesting for me to sign-in, I do but the app doesn't show that I am. I can't use my premium features when writing.