3D acceleration with virt-manager

I am using a NixOS unstable as a virt-manager/Qemu VM on NixOS unstable using the same flake config see here. I set the Video to “virtio” and set “3D Acceleration” checkbox in the GUI, enabled the guest tools in the guest and rebooted the guest, . However “glxinfo” on the guest still reports llvmpipe as the renderer. I expected “virgl” or similar. Does anybody has a setup with working guest 3D acceleration? If yes, how do you configured it?