Comment 6 for bug 1314829

In situations where there are more than one /backdrop/screen0/monitor entries, and the first entry is _not_ the valid entry, Ristretto does not change the wallpaper for that monitor property. It only affects the first entry. The end result is that the desktop wallpaper is not changed.

I have seen this in two separate scenarios:

1. Xubuntu 14.04 as a Virtualbox guest. On install, the /backdrop/screen0/monitor0 property is created. When the virtualbox additions are installed, a second property, /backdrop/screen0/monitorVBOX0 is created. The second monitor property is the active one, but Ristretto only affects the first monitor property.

2. Arch Linux install with nvidia driver. On install, the /backdrop/screen0/monitor0 property is created. When the properietary driver is installed, a second property, /backdrop/screen0/monitorLVDS0 is created. he second monitor property is the active one, but Ristretto only affects the first monitor property.

Changing the wallpaper from within xfdesktop-settings works, so that module must know which is the active monitor. That same code should probably be used here.