Rated 4 out of 5 stars
Works great on Jupiter itself ;)
The only thing bugging me is the button to access the menu with the tabs beside it and the favorites tool bar that makes everything ugly because of the line separator with the address bar, but I suppose it's part of Firefox itself, right ?
actually you should install the "movable firefox button" here: https://addons.mozilla.org/en-US/firefox/addon/movable-firefox-button/ to be able to move the menu button next to the address bar, like in the elementary guidelines. about the favorites bar, it is possible to remove that line, but this work is based on elementary mockups, which have some sort of separator line. I'm working on a new version, with a much better favorites bar. I'll release it soon.