After Stable Update 2021-09-24 LightDM no longer automatically start

[pheiduck]

Other solutions are:

Lightdm failed to start with Kernel 5.11.14

Put amdgpu to your modules in mkinitcpio … https://wiki.archlinux.org/index.php/Kernel_mode_setting#Early_KMS_start

[Stable Update] 2021-08-27 - Kernels, Cutefish, NetworkManager, Gnome, Pamac, Mesa, Browsers, Xorg-Server, LibreOffice

I also had the problem that LightDM failed during startup. For me adding logind-check-graphical=true to the [LightDM] section in /etc/lightdm/lightdm.conf did the trick.