You can use multiple profiles with Firefox, the UX for doing so just isn't as fleshed out as Chromium. Create a new profile by going to about:profiles, and the

You can use multiple profiles with Firefox, the UX for doing so just isn't as fleshed out as Chromium. Create a new profile by going to about:profiles, and thereafter when you start Firefox it should present you with an option to pick which profile to use.