I think that's for Gnome App developers and not for regular users.
Firefox Containers are for Cookies and Storage separation. Profile, on the other hand, is a COMPLETE separation in all aspects of Firefox's user data, setup , add-ons.
Always use a separate Firefox profile for banking needs.
Ubuntu 24.04 + Gnome 46 + Wayland + Nvidia Rtx 3070 Ti + Driver v555 + Kernel v6.9.3
UX is a very subjective matter.
Bad news is that it is not clear at this point whether Mozilla is going to go forward with the implementation. A post on Reddit by one of the project members suggests that the build is a "rough proof-of-concept". Some features tested in the build "did not survive". It is unclear which did not, as they are not mentioned. Mozilla is, however, implementing those that survived the cut into Firefox. Again, the poster does not mention which those are. It is also not verified that the poster is actually a member of the project team, so take this with a grain of salt as well.
All of these are signs of persistent threat actors aka State sponsor hacker. Though the real motive we would never know as it's now a failed project.
Source: https://turnoff.us/
There is a work-in-progress version of Firefox for iOS with Gecko engine.
But, there is also a challenge that Mozilla is facing as Apple is still trying to make life of developers of other browsers as difficult as possible.
So, not sure how the whole thing will turn out.
Whenever you have issue with Firefox, first thing that you should try is 'Troubleshoot mode' -
Firefox Menu > Help > Troubleshoot Mode