Comment 3 for bug 1714203

Thank you for your bug report. It works here, from the description it looks like gdm might consider that wayland can't be used on your video driver and lists only x11 sessions as a result. Since you have one 1 session to list in that case it also explains why the cog has no list.

Could you enable gdm debugging in /etc/gdm3/custom.conf and see if the logs have any hint about that