Lightdm settings doesn't work?

[ironfoot]

Hi, @smurf!

There are different greeters for lightdm. Ubuntu MATE is currently using arctica-greeter, which has no dedicated configuration tool. The lightdm-settings package shall work with slick-greeter, lightdm-gtk-greeter-settings -- with lightdm-gtk-greeter.

Use the same approach you have used for 22.04:

How to change the lightdm background image in the greeter window'

Recently I upgraded to Ubuntu Mate 22.04, I wish to change the background image in the greeter window, but lightdm-settings seems not to work, because it change nothing. What's wrong?