/usr/share/nemo/actions/change-background.nemo_action is in nemo-data 2.2.4-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 | [Nemo Action]
Name=Change Desktop _Background
Comment=Change Desktop _Background
Exec=cinnamon-settings backgrounds
Selection=None
Icon-Name=cs-backgrounds
Extensions=any;
Dependencies=cinnamon-settings;
Conditions=desktop;dbus org.Cinnamon;
|