Gnome Display Manager (gdm) and XTEST

Hi, I've recently discovered that steam client on linux requires the XTEST extension to handle input from controller. However, I can not enable XTEST on gdm no matter what I've done. Switch to lightdm solves it instanly but I prefer gdm.

Could you provide some hint how to debug it and have you experienced that before? Thank you very much!

I am using Arch Linux with Gnome and Wayland.