For me editing the display-manager.service made no difference.
[Service] # temporary safety check until all DMs are converted to correct # display-manager.service symlink handling #ExecStartPre=/bin/sh -c '[ "$(basename $(cat /etc/X11/default-display-manager 2>/dev/null))" = "lightdm" ]' ExecStartPre=/bin/sleep 10 ExecStart=/usr/sbin/lightdm Restart=always BusName=org.freedesktop.DisplayManager
So I will keep restarting lightdm 3 times per boot
For me editing the display- manager. service made no difference.
[Service] manager. service symlink handling /bin/sh -c '[ "$(basename $(cat /etc/X11/ default- display- manager 2>/dev/null))" = "lightdm" ]' /bin/sleep 10 /usr/sbin/ lightdm org.freedesktop .DisplayManager
# temporary safety check until all DMs are converted to correct
# display-
#ExecStartPre=
ExecStartPre=
ExecStart=
Restart=always
BusName=
So I will keep restarting lightdm 3 times per boot