Comment 6 for bug 1820840

I've triggered a test build of the desktop ISO now so we can confirm it's doing what's expected with livecd-rootfs 2.576, but per Tobi this is not a complete solution per comment #3 and we cannot unseed core18 from the desktop seed (we need https://code.launchpad.net/~mwhudson/livecd-rootfs/+git/livecd-rootfs/+ref/no-snaps-ubuntu-cpc-minimized for that) so setting this back to 'in progress'.