I suppose it is not all that easy to test older versions of qemu, libvirt, etc for TW. AFAIK, older snapshots are kept under https://download.opensuse.org/history/, but adding those repos one by one, installing the packages, and checking the result would be tedious. I did a little "bisecting" of my own and found that the issue exists on my laptop, which runs TW 20220426. The issue also exists on one of my test machines running latest TW. Interestingly, the issue does not exist on SLES15 SP4. qemu is at the same version among all of those hosts, but the libvirt versions are quite different. But I build the latest TW libvirt for SLES15 SP4 and it worked fine on my SP4 host. Perhaps there is some small qemu configuration difference between TW and SLE causing the issue?