opengl application take too long to start on Fedora 40

[totaam]

Running glxgears from an xterm takes 4 to 5 seconds before we get the "new-window" event in xpra.

No noticeable delay with vglrun or even strace -f glxgears!
But there is a delay with strace glxgears!

Looks like it's trying to load a driver, (vulkan and opengl?), running modprobe and searching /dev/dri, /sys/devices/pci*, etc

I don't think that there's much we can do about this without potentially breaking vglrun or some other unexpected rendering context.

[totaam]

nouveau was active - I just rebooted with the nvidia module instead and the problem is gone!

Doesn't happen with the Intel driver either, not tested AMD yet.