Mozilla is behaving like this extension is not installed, but I installed it few times. Icon is present in top bookmarks toolbar. When you click an icon menu appears, and you can add a text, change language....but it doesn't translate at all. If you select a text on a page, right click on selection translate, a "balloon " shows up with "loading" written in it, but it doesn't conclude the translation. This extension doesn't do what is designed to do.