Reminds me of VirtualBox on Wayland. It won’t correctly capture the mouse, so it just exits and re-enters the window in random positions. Say, on guest you see it in middle left, you move it a bit to the right, and it jumps out of bottom right corner.

So, time to have a second mouse, and do USB passthrough.

But also UEFI on my HP mini PC doesn’t work with every keyboard, so a second keyboard for UEFI.