System crashed not long after startup, since then no more AppVMs bootable

Thank you very much. Solution for me is:

sudo lvs

Then search the list for “snap”. For every matching entry I do:

sudo lvremove qubes_dom0/vm-exampleVM-root-snap

Or:

sudo lvremove qubes_dom0/vm-exampleVM-private-snap

Then the AppVMs are bootable again.