From their repo:
Plasma Login
Plasma Login provides a display manager for KDE Plasma, forked from SDDM and with an new frontend providing a greeter, wallpaper plugin integration and System Settings module (KCM).
What we want
- Great out-of-box experience in multi-monitor and high DPI and HDR
- Keyboard layout switching
- Virtual keyboards
- Easy Chinese/Japanese/Korean/Vietnamese (CJK) input
- Screen readers for blind people (which then means volume control)
- Remote (VNC/RDP) support from startup
- Deeper Plasma integration including:
- Display and keyboard brightness control
- Full power management
- Pairing trusted bluetooth devices
- Login to known Wi-Fi for remote LDAP
Things I’ve run into:
Out of the box, the lock screen comes on after screen unblanking - late enough that when things aren’t snappy you can briefly catch the desktop without reauthing.
Sometimes randomly after wake, keyboard input is not recognized in the password field at all. Except for Esc, which in this state appears to crash-restart it and makes it work again
With a multi-monitor setup, I have still not been able to properly force the primary monitor. Is an issue because things like notifications and the login input will only show up on a usually turned off projector. This one might be PEBCAK.
I have issues 1 and 3 with XFCE on lightdm, too, though.
SDDM does lock screen? But that’s a screen locker’s job. In this case, you can likely disable it in some ssdm.conf and use any alternative locker instead (also note the List_of_applications/Security#Screen_lockers there).
I have the same multiple monitor issue. I have an ultrawide on display port, and a smaller monitor on hdmi. Boot messages default to the ultrawide but the login prompt also defaults to the secondary display. Minor thing I know, but irritating.
I’ve definitely noticed #2 and #3, very annoying! They should both show the same text input (not a straight display clone since they might be different resolutions/ratios)
On a side note, I’ve noticed some Linux installers don’t handle multiple screens well or high resolutions. I think Calamares is a big offender here, it doesn’t clone to every display so I end up stuck trying to use my sideways monitor. Or on a 4k screen everything is tiny for no reason, it should just default zoom on high resolution.
I much prefer the installers that are just a regular window on a normal desktop, where you can move it, maximize it, easily access the DPI settings and other system settings, browse the internet while it’s installing…
The lock screen and display manager are two separate pieces of software. The display manager runs before a user profile has been selected for graphical login, so it does not have access to your user desktop/display settings
there’s a button to apply Plasma settings to SDDM for this purpose, it prompts for admin password when you do it, which makes sense
Supposedly both the display manager and greeters have system-wide configuration for this purpose, however. And the issue with notifications and DE overlays are present post login, too.