os: gentoo
cinnamon 3.0.7
gentoo use patch

when i run cinnamon-settings
Loading Backgrounds module
Failed to read filename from /usr/share/backgrounds/gnome/adwaita-timed.xml: list index out of range
Failed to detect mimetype for None: execv() arg 2 must contain only strings

yes. i'm was reproduce it on cinnamon distro: install gnome-backgrounds and drop adwaita.xml into /usr/share/cinnamon-background-properties. looks like cs_backgrounds.py was trying work with xml as with regular image file