Works well enough, though it's misleading to say it counts words with 1 click. It doesn't. The process is (select text > right click > Mouse-over 'Word Count' > left click 'Count Words'). Would be much better if it displayed the word count upon right-clicking the selected text, then offer the extended menu.
Benjamin, I am not the kind of person who usually bothers to writes reviews for add-ons. If something doesn't work, I move on to something else, but I believe this app is exactly what I need for my job and you have seemed open to feedback. I am still having the same issue--works the first time but not after that. Could it be that I am using a company website and not something that everyone has access to?