Firefox has its own profiles, which are separate from containers.

`about:profiles` shows you a window for creating and switching to a different one. I add that as a bookmark on the bookmarks toolbar of the two profiles I use

I believe there is a `-P` option to open a new window with a specific profile. I do not use it. I usually just open the browser and then go to the aforementioned bookmark and open the other profile.

I use different colorways to differentiate the windows between the two profiles.

There may be addons that alleviate a few of the pain-points with Firefox profiles. I have not tried to find any.