How to enable custom wallpaper change in lightdm-gtk-greeter?

Question

linux

I installed Debian 11(xfce) and the lightdm-gtk-greeter-settings package . In lightdm-gtk-greeter-settings, I configured everything for myself and checked the box next to "Use a custom background if possible", but when I rebooted, the wallpaper did not change to custom, but remained standard.
How can I solve this problem and where should I "dig"?

Answer 1

After 10 hours I was able to solve the problem.
In my case, I just had to install the accountsservice
sudo apt install accountsservice
package And then reboot the system twice.
And all the wallpaper change to custom (from the user's desktop) works!
Thanks everyone for the help! And all the best to you!

Answer 2

Wallpaper of what? Login windows or boot screens?
show lightdm-gtk-greeter.conf
file name may be different, show what is in /etc/lightdm/lightdm-gtk-greeter.conf.d

mine looks like this

[greeter]
background=/usr/share/backgrounds/linuxmint/default_background.jpg
theme-name=Mint-X
icon-theme-name=Mint-X
font-name=Ubuntu 14
xft-antialias=true
xft-dpi=111
xft-hintstyle=hintslight
xft-rgba=rgb
indicators=~host;~spacer;~clock;~spacer;~session;~a11y;~language;~power
keyboard=onboard
reader=orca
position = 50%,center 50%,center
default-user-image = #avatar-default
screensaver-timeout = 60
a11y-states=contrast;font;keyboard;reader
user-background = false
clock-format = %a %d %b, %H:%M