Seperate data system and seperate network stack. Browser has no access to the host system. Only the host system uses the own graphical interface to access the jail/firefox with GUI
Yeah, it does. I use sway (wayland) on FreeBSD and it works great and wasn't harder to set up than on Linux. In fact, it works better for me on FreeBSD than on Arch Linux because the sway vulkan backend works for me on FreeBSD but not on Linux. Maybe they're suggesting piping wayland out of a pot jail is harder?