Allow capture desktop image possible? Other parameters.

[cdplayer]

Expected behaviour

the flipscreen3d saver(et al) is expected to capture the desktop to animate it moving around the screen.

Actual behaviour

On linux mint mate default behaviour appear to use a 'fallback' test item. Sort of looks like old school tv test signal.

Steps to reproduce the behaviour

No special steps.

MATE general version

MATE Desktop Environment 1.22.2
mate-screensaver 1.22.2

Package version

Linux Distribution

Linux Mint 19.3 'Tricia'

Link to downstream report of your Distribution

Other:

For Xscreensaver there is a attribute "grabDesktopImages: True" that the UI adds to a file at ~/.xscreensaver
This is not used as far as I can tell in the mate-screensaver but I don't know and can't find how to change particular attributes. My understanding mate-screensaver is a lite or more compatible screensaver than xscreensaver but thought I should be able to enable this similar functionality from the command line or a file.