Excellent extension Rated 5 out of 5 stars
I suggest that you use https://www.google.com/search?tbs=dfn:1&q= instead of wiktionary. The google dictionary is more complete and has more pronunciations. The ability to specify where the website inside the popup comes up would be nice (with X,Y coordinates).
All in all, this is the best dictionary extension I've seen for Firefox because it can use Google's dictionary and because it works even after Clearly is used on the webpage (although, only the keyboard shortcut works, the "Define now" option doesn't appear in the context menu once Clearly is applied). Good job!
UPDATE: Have added a Google Dictionary extension below now.
Thanks a lot for your review. I have made wiktionary and freedictionary.com extensions so far. Have implemented what I could from your suggestions as best as possible. Mozilla's objects like the pop up screen are still fairly limited right now. But they may add new features in time. Of course, as you found out, the web url can be changed in this extension to use Google dictionary instead of Wiktionary.If you come back around here again can you specify what you want by x y coordinates and why?
Just realized this, you can left click and drag any link inside of the panel and drop it into your Firefox address bar to go there directly. Helps a bit.