According to apt-file usr.lib.snapd.snap-confine.real seems to be from snapd:
$ apt-file find usr.lib.snapd.snap-confine snapd: /etc/apparmor.d/usr.lib.snapd.snap-confine.real ** Attachment added: "usr.lib.snapd.snap-confine.real" https://bugs.launchpad.net/ubuntu/+source/snapd/+bug/1814141/+attachment/5236593/+files/usr.lib.snapd.snap-confine.real -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1814141 Title: fail to run any snap after snapd refresh, reinstalling snapd from the archive is a temporary fix To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/snapd/+bug/1814141/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
