Hi. Can confirm this. It doesn't only happen on clones, but also when one manually creates a new VM and uses a pre-existing image for it.
Interestingly... it seems not only to cause virt-manager to break... but also libvirtd... I really have to kill -9 libvirtd and restart it before anything works again.... just killing virt-manager, and it still cannot connect to libvirtd respectively freezes immediately again. Cheers, Chris.
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