Package: cups-daemon Version: 2.2.10-6+deb10u3 Severity: normal The cupsys group was added to users-and-groups in 2005 (#290237). I don't remember if cups used to run as such user back then, but now it (very unfortunately) runs as root, and no such user is present in the system. This is at least the case for the default cups-daemon package. Please drop this user from the document.