I built a userChrome.js replacement [+] back when FF 57 came around, that uses an XBL loophole to permit users to add custom javascript to their profiles that w

I built a userChrome.js replacement [+] back when FF 57 came around, that uses an XBL loophole to permit users to add custom javascript to their profiles that would run in the browser context. I wanted to be able to use pre-OS X Lion fullscreen mode, and couldn't find any other way to do it. I'm a little bummed that this loophole is going away in FF 72 (I still can't get pre-Lion fullscreen!). On the other hand, it has always been super clear that this is a loophole that will eventually go away, and I did get 2 years of use out of it, so I'm not complaining too loudly. Congrats to the team for removing XBL! [+] https://github.com/nuchi/firefox-quantum-userchromejs https://github.com/nuchi/firefox-quantum-userchromejs