The unattended install for XUbuntu 22.04 is working in 7.0.0. beta 1. It did not work in 6.1.x.
This will same me allot of time when I need to recreate a XUbunutu 22.04 using scripts to create a reproducible VB setup.
I would also assume that Ubuntu 22.04 would also work as it also failed on 6.1.x with the same problem.
My test did not check if the "--post-install-command" worked as it did not in Ubuntu 20 or LM 20.0 on 6.1.x.