Display manager

From postmarketOS Wiki

List of display managers

  • tinydm, default on Phosh, Plasma Mobile and LXQt installations
  • lightdm, default on Xfce4 and MATE installations
  • gdm, default on GNOME installation
  • sddm, default on Plasma Desktop installation
  • lxdm, not used by default

tinydm

The tinydm log file can be located in ${XDG_STATE_HOME:-~/.local/state}/tinydm.log.

LightDM

In Xfce4 and MATE, autologin is preset by the files /usr/share/lightdm/lightdm.conf.d/64-autologin.conf (Xfce4) or /usr/share/lightdm/lightdm.conf.d/61-autologin.conf (MATE).

If you want to use LightDM as a login screen, it can be set up as follows:

1. sudo apk add lightdm-gtk-greeter

2. sudo vi /etc/lightdm/lightdm.conf

change:
greeter-session=lightdm-gtk-greeter
greeter-hide-users=false

3. sudo vi /etc/lightdm/lightdm-gtk-greeter.conf (optionally)

Background picture can be set here.
Also setting up a virtual keyboard can be done here. Keyboard onboard is preinstalled on Xfce4 and MATE. First line is a change, the other two lines are new additions. On bigger screens, layout "Phone" can be replaced by layout "Compact".
background=/usr/share/wallpapers/postmarketos.jpg
theme-name=postmarketos-dark

keyboard=onboard -l Phone -t Nightshade
keyboard-position="50%,center -0;100% 25%"
a11y-states=+keyboard

4. sudo vi /usr/share/lightdm/lightdm.conf.d/65-autologin-override.conf (new file)

Finally, to disable autologin, the content of the autologin config file can be overriden and set to empty by:
[Seat:*]
autologin-user=
autologin-user-timeout=
autologin-session=

CanGraphical issue

If LightDM starts but there is no picture on screen, check if loginctl show-seat seat0 reports it as CanGraphical=0. If that is the case, in /etc/lightdm/lightdm.conf replace #logind-check-graphical=true with logind-check-graphical=false to make LightDM ignore that nonsense.

loginctl does not see the session

Enable virtual terminals in your kernel config.