Display Server Preference Icon does not show up in gdm3.

[KAWAKAMI, Kensuke]

1) The release of Ubuntu you are using, via 'lsb_release -rd' or System -> About Ubuntu

 Description: Ubuntu 22.04.2 LTS
 Release: 22.04

2) The version of the package you are using, via 'apt-cache policy pkgname' or by checking in Software Center
 gdm3/jammy-updates,now 42.0-1ubuntu7.22.04.1 amd64

3) What you expected to happen
 A preference icon is displayed at the bottom right of the login screen, and you can switch between xorg and wayland.

4) What happened instead
  Icon does not show up in gdm3.

[Daniel van Vugt (vanvugt)]

The icon is not displayed in cases where the system can only determine one session type. So offering a menu with only one option would be pointless. If you think this is an error then please run:

  lspci -k > lspci.txt
  journalctl -b0 > journal.txt

and attach the resulting text files here.

[KAWAKAMI, Kensuke (kenchanprfm)]

Sorry.
I check my conf file again, I found wayland has disabled by "/etc/gdm3/custom.conf".
After I edit "WaylandEnable" parameter in "/etc/gdm3/custom.conf", the icon showed up on gdm3.