Для openSUSE Tumbleweed запустите от имени root:
zypper addrepo https://download.opensuse.org/repositories/X11:Wayland/openSUSE_Tumbleweed/X11:Wayland.repo
zypper refresh
zypper install greetd
Для openSUSE Slowroll запустите от имени root:
zypper addrepo https://download.opensuse.org/repositories/X11:Wayland/openSUSE_Slowroll/X11:Wayland.repo
zypper refresh
zypper install greetd
Для 16.0 запустите от имени root:
zypper addrepo https://download.opensuse.org/repositories/X11:Wayland/16.0/X11:Wayland.repo
zypper refresh
zypper install greetd
Для 15.6 запустите от имени root:
zypper addrepo https://download.opensuse.org/repositories/X11:Wayland/15.6/X11:Wayland.repo
zypper refresh
zypper install greetd