Hi
Apologies right at the beginning for the size of the screen shots.
I have an issue where when I run the following xrandr command on my middle monitor - Mate does not appear to cope with the request very well.
xrandr --output DP-4 --scale 1.5x1.5
Pre command > 
Post Command > 
Post Command Cupertino > 
Hopefully you can see the wallpaper does not scale properly and 2ndly the Cuprtinto panel does not sit on the bottom of the screen.
Now I realise this is a very unusual configuration but most if not all other Distro's I try can cope (with the exception of Budgie - but that is a whole other story)
No matter what I do or in what order - I cannot get Mate to play ball either with the bottom panel or the wallpaper.
Any ideas ?
Regards Zeb...