I am trying tu execute you solution but i receive the following error:
debian@vps-fdabfaff:~$ sudo curl -fsSL https://rc.download.virtualmin.dev/repository | sh -s -- -s -B pre-release
grep: /etc/virtualmin-license: Permission denied
grep: /etc/virtualmin-license: Permission denied
[INFO] Setup log is written to /home/debian/virtualmin-repos-setup.log
sh: 751: swapon: not found
[ERROR] Fatal Error Occurred: Fatal: The Virtualmin install script must be run as root
Cannot continue installation.
mv: inter-device move failed: '/tmp/.virtualmin-2141574/sources.list.2141574' to '/etc/apt/sources.list'; unable to remove target: Permission denied
[WARNING] Removing temporary directory and files.
[ERROR] If you are unsure of what went wrong, you may wish to review the log
[ERROR] in /home/debian/virtualmin-repos-setup.log
Thank you, Ilia — it works perfectly.
One last question: when the final version of the installer becomes available, how can I switch back to the normal repository?