I cannot find the icon anywhere on my screen so I've not been able to use this extension. I'm very upset. the spell check I had in the last edition of Firefox was perfect for my uses. I'm frustrated and angry there is nothing similar offered in this edition.
Basic words like "relatable" are obviously in there. So many reviewers here seem to be completely clueless. Try to make sure you're actually using the dictionary you're reviewing before leaving angry 1-star "reviews"! You have to select it, you know.