Does firefox actually have a complete manual? One that accurately covers the behavior of every option in about:config. I'd love to be able to diff one file to see what things they've screwed with this time when I update.
Heck, MDN doesn’t even have full documentation for >10 year old tech Mozilla was tightly coupled to in the same time frame. Try discerning how to use XML-related features in a browser and you’ll very quickly find yourself trying to extrapolate from C/Java/even PHP stuff that might be tangentially related but probably isn’t, from increasingly less relevant websites. I couldn’t read the manual even though I tried.
