I’ve watched half of the video and gotta say it all sounds very complicated. And since I don’t know exactly what changes are made or options set back to default with that cleaner-script I decided to just get through every entry in the user-overrides.js provided. In hindsight this was a good idea because I know some of these changes in the settings would have broken stuff for me. Actually I didn’t have to change a single option because my Firefox was already hardened enough. ;) At least I now know I’m good and have been good.