SDDM (https://github.com/sddm/sddm) is a desktop login manager. In Arch Linux you can install and enable it with the following commands:
sudo pacman -Sy sddm sudo systemctl enable sddm
Disable any other login manager, then reboot and then you can use SDDM.
Sadly as of version 0.18, SDDM still lacks proper Wayland support in 2020, it is not even available for testing, even though the activity has been started long time ago. SDDM is released infrequent from time to time.
SDDM’s default theme is ugly, so change it to the breeze after installing KDE Plasma via the system settings.
sudo nano /etc/sddm.conf.d/autologin.conf
sudo nano /etc/sddm.conf [Autologin] User=john Session=plasma.desktop
If you have this issues with the stable release or you want to test the development version, you can always try the SDDM-git development code:
If SDDM fails to start and you have a black screen, often there is an issue with the graphic driver. Read X.org.log for details.
- Wayland support still not finished yet, development seems to have slowed down a lot without a status report https://github.com/sddm/sddm/issues/440
- SDDM on a virtual machine cannot set the correct resolution. Bug SDDM 0.14..0.17 https://github.com/sddm/sddm/issues/576#issuecomment-336604993.
- Very small mouse cursor on 4K screens, it doesn’t scale.
If you need a true Wayland display manager or if SDDM refuse to work at all, you can try GDM. Unfortunately it enforces most of the gnome-session as a dependency.