A very useful, well-made, and (at first glance) trustworthy extension. Also, seemingly the only Firefox extension that can replicate Chrome's full-page translation ability (even using the same translations, as it appears to use Google Translate in the back-end).

I tend to use many tabs (30-50 tabs loaded and 100+ sleeping tabs) and then this extension unfortunately becomes a bit of performance liability.

Curiously, the Firefox task manager shows the extension always springing into action when switching to a different tab.