A respected member of the community noted a while back that:
“There is one thing I don’t use Debian for: The Update VM (which may be sys-net or sys-firewall, but you can assign it to a separate VM). The reason is that dom0 uses rpm/dnf and Fedora template is needed to handle it properly.”
https://groups.google.com/g/qubes-users/c/HHedtfDFdj4/m/eUCrs98PDgAJ
I forgot about this and have been using Debian as my UpdateVM for a while now. I haven’t encountered any issues so far (that I know of) in both R4.1 and R4.0.3, so I was wondering if this piece of advice is still valid.