I have a single VM on unraid, a Ubuntu Server machine with no GUI and no fancy settings, no GPU. It's network is set in bridging mode. After upgrading to rc3, without changing anything in VM, it stopped seeing network, getting IP address. 'ip a' reported network device down. I could only access machine with built-in VNC. My router also reports the virtual machine "offline"
After installing rc4, VNC stopped working too. It shows black screen with "Guest has not initialized the display yet". Now I have no access to virtual machine at all. But I am sure it works, judging by CPU consumption.
I have tried creating completely new VM with Ubuntu Server install .iso, and have the same result. I tried switching network to virtbr0, but got the same result ( router does not report attempting to do a connection that my VM should do automatically )