I also have a computer not yet updated (still on 4.0.0-beta3-0ubuntu3) and /etc/apparmor.d/bwrap-userns-restrict does not exist on that computer.
I also have a computer not yet updated (still on 4.0.0-beta3- 0ubuntu3) and /etc/apparmor. d/bwrap- userns- restrict does not exist on that computer.