No matter what I try, I can’t access LightDM GTK+ Greeter settings. When launched from the main menu or Xfce settings, it asks for root password an then nothing happens. The only way I can even see the GUI is by running lightdm-gtk-greeter-settings, in which case I don’t have permission to change anything. running sudo or lightdm-gtk-greeter-settings-pkexec gives me the same result, with the following error output:
http://txt.do/18ar3
I am using Xfce on Tumbleweed.
Thank you.
I do not use Xfce nor lightdm, but reading
man lightdm
tells me about configuration files in /etc/lightdm
boven:/etc/lightdm # l
total 28
drwxr-xr-x 2 root root 4096 May 16 2020 ./
drwxr-xr-x 144 root root 12288 Dec 22 09:32 ../
-rw-r--r-- 1 root root 40 May 16 2020 keys.conf
-rw-r--r-- 1 root root 820 Feb 14 2020 lightdm-gtk-greeter.conf
-rw-r--r-- 1 root root 432 Sep 17 2014 users.conf
boven:/etc/lightdm #
Strange enough there is no lightdm.conf, but there is lightdm-gtp-greeter.conf
In any case those file have comment that should tell you what you can configure and how.
HTH.
Thank you, that helps since I can change the background image at least. But I would like to be able to use the GUI app if it’s there…
I’m not a LightDM user, but the following Debian guide…
https://wiki.debian.org/LightDM#Viewing_current_configuration
…contains a note…
User configuration LightDM itself has no user configuration. Once you’ve authenticated with your username and password, LightDM will run an X session. If you wish to configure your login environment, you must use the configuration files for whichever type of X session your system is configured to use.
I had the same problem when I moved from Leap 15.2 to TW and switching to another theme made it working as it should (I’m using a regular Greybird GTK theme, not one provided by openSUSE right now that’s installed on /usr/share/themes).
hth
It doesn’t want sudo but su to open lightdm-gtk-greeter-settings.
I’m using tumbleweed and I can open it in xfce settings manager after providing the root pasword and can modify the user image, theme etc.
However I don’t want to mess with it because I’m satisfied using the sddm presently as my displaymanager.
I’m using xfce 4.16 now but even in the 4.14 version there was no problem.
Just curious, what is the output of
update-alternatives --config default-displaymanager
Yes! That did it. I appreciate it.
Coming from Ubuntu/Mint side here hehe, not used to actually using su 
Output is
Absolute path to 'update-alternatives' is '/usr/sbin/update-alternatives', so running it may require superuser privileges (eg. root).
Thank you thank you.
Ps. Based on this I’m assuming if I logged in to a session as root I’d be able to open it with an icon click. I don’t care to try though. All I wanted was font previews…
Bad idea to log into any GUI as root. Excellent chance of breaking things :’(
Not to login as root, just open the lightdm GTK+Greeter in xfce4 settings manager it will ask for the root password.
Use su also first in terminal and do
update-alternatives --config default-displaymanager