No background setting in MATE

[Splinx64]

Hi Sparkies,

since my last update yesterday my set background wallpaper is lost. And, I cannot set a new one.

I have seen, that after the update the mate-control-center was deinstalled - I have had to reinstall it.
Now I can select an desired image, but it has no effect. I only have a gradient as background.
To set the background image via context menu on screen also doesn't work.

Other settings, such as window frames and fonts, work.

What can I do set my desired Background image? Is there another missing package? Have you any idea?

I use the Sparky testing release with a MATE desktop.

Thank you in advance for your help