Display managers like SDDM, the one recommended for
LXQt, or LightDM are looking for
available sessions in files $XDG_DATA_DIRS/xsessions/*.desktop where $XDG_DATA_DIRS is set to /usr/share/ most of the times.
LXQt is providing a file lxqt.desktop so its session
should normally be detected and made available by display managers
automatically, restarting
the latter may be needed upon installing LXQt.
Note if LXQt was installed in /usr/local file lxqt.desktop is stored
in /usr/local/share/xsessions which is not considered
by most display managers. So you'll either have to copy the file to /usr/share/xsessions/ or create a symbolic
link.
Fixing crashes for apps using dbus-daemon (common when using lxqt-config-monitor)
Important: This applies only to systems running systemd which have this problem.
On some systems (like the default ArchLinux install), dbus-daemon is started as a systemd service before the xserver thus
it has no $DISPLAY variable set in it's environment, leding to crashes. Systemd by default includes
a script to fix this by fetching the variables in /etc/X11/xinit/xinitrc.d/50-systemd-user.sh. If you encounter this kind
of crash add the following lines to your .xinitrc before exec startlxqt
if [ -d /etc/X11/xinit/xinitrc.d ] ; then
for f in /etc/X11/xinit/xinitrc.d/?*.sh ; do
[ -x “$f” ] && . “$f”
done
unset f
fi