libvirt users - Oct 2019 - win10 vm stuck in automatic repair

Hello,

I have a Windows 10 guest, when I boot it, it goes in to Automatic
Repair mode, and after some time reports it was unable to repair the PC.

This is from an older snapshot ("snapshot1"), and if I try switching
back to a more recent snapshot ("snapshot2"), libvirt reports that it
can't find the snapshot:
> libvirt.libvirtError: internal error: Child process (/usr/bin/qemu-img
> snapshot -a snapshot2 /var/lib/libvirt/images/win10.qcow2) unexpected
> exit status 1: qemu-img: Could not apply snapshot 'snapshot2':
Failed
> to load snapshot: Invalid argument
Does anyone have any ideas why this might have happened, or any
suggestions for how I can go about diagnosing/fixing this?

This was a pretty simple Windows 10 VM, that I used for Microsoft
Office. Everything was managed through virt-manager and most settings
left at the original defaults.

Thanks,
Jack

It seems like I might be affected by this recent qemu 4.1 bug:

https://bugs.archlinux.org/task/64150
https://bugzilla.redhat.com/show_bug.cgi?id=1764721
https://lists.gnu.org/archive/html/qemu-block/2019-10/msg01414.html

I'm not 100% sure. But the second link mentions the easiest way to reproduce
this bug is by using snapshots, which lines up with my experience.