Picture on other monitors overlaps primary screen if file resolution is higher than screen itself #73

While using the Login Window application, if I set a background image for "Other monitors', the picture overlaps the primary monitor.
Figuring out the issue I discovered that, if the file resolution is higher than the screen itself, the image didn't scale correctly thus appearing on all monitors in order to fulfill the "canvas".

I use two 1920x1080 monitors, in this example.

Files used:

• Primary: /usr/share/backgrounds/linuxmint/sele_ring_center.jpg (3840x2160)
• Other monitors: /usr/share/backgrounds/linuxmint/sele_ring_center_green.jpg (3840x2160)

OS: LMDE 7