[lucb1e]

Had I known this earlier... I had the same reaction as the person you replied to, I hadn't thought of using profiles. I knew something called profiles existed, but I thought it was not in use anymore (at least not properly supported). I never connected the dots.

Still sounds like a pain to manage though, compared to this new feature.

[sp332]

Yeah it's not a great user interface, and it's definitely buried. Aside from the Developer Edition which uses a different profile by default, it seems to be ignored by Firefox devs. Probably because they don't want to support all the people who get confused by the terrible UI!