Osmos
yay -S lightdm-webkit-theme-osmos
Or set greeter-session=lightdm-webkit2-greeter in /etc/lightdm/lightdm.conf, then edit /etc/lightdm/lightdm-webkit2-greeter.conf to set webkit_theme=lightdm-webkit-theme-osmos.
greeter-session=lightdm-webkit2-greeter
/etc/lightdm/lightdm.conf
/etc/lightdm/lightdm-webkit2-greeter.conf
webkit_theme=lightdm-webkit-theme-osmos