When I want that sort of separation, which I do between work and play, I run browsers (and everything else) as different users. That works with any browser and I don't even have to worry about bugs in profile or container separation, and it reduces (though of course didn't remove) the chance of idiot here using the wrong instance for the wrong use. Heck, where possible I even use a separate machine. DayJob provide a PC on the office that I remote into (via VPN+RDC) for work purposes, so the contact point between that work and everything else is minimal (in fact my main desktop is a VM I "remote" into, I only use the base metal when I take have too which is usually things unhappy running that way (Bambu Studio and games, which do not like the lack of faf free access to the GPU)). You can still access everything from one machine, or even have the different users instances on the same desktop (this does reduce the barriers a touch though).

The only real cost is that running things this way eats more memory, but I've not experienced OOM issues for years away from deliberately small VMs (for testing or small sever tasks) that turned out to be too small.