One of the Firefox add-ons which I find myself using frequently is WordCount Plus, which sits down in the status bar of Firefox. It provides a word count of any chunk of text that you select and highlight.
This is something I often need to do in my online classes, where I have both minimum and maximum word counts for the assignments. If it looks like a student has written way too much, or way too little, for a particular assignment (in a blog post, on their webpages), this little Firefox add-on gives me a quick way to check to see if my guesstimate is correct. I also recommend that my students install this same add-on so that they can check their own work in advance - it's definitely better to find the problem and fix it before I discover the problem myself! :-)
For example, while I am typing this blog post, I can highlight what I have typed in the form box and right-mouse click, bringing up the option to do a word count.
The result then shows up in the status bar, next to the little WordCount Plus icon.
You can do a word count like this for text you are typing in a form box, or you can do a word count for content published on a webpage - anything that you can highlight, Word Count can count for you. It's a super little add on, very efficient, easy to use, and unobtrusive.
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