What would js be able to do out of firejail or other such forms of containment?
I only allow js for very specific sites, and most that you can't do without I just do without. I am not that worried about security though, it is just an exercise.
I use seatd with wayland but it can be compiled without it too. My main issue is as I said, I can't just run "sudo -u user2 leafpad" for example, you say it is a security measure, I say it is an inconvenience.