This is an enhancement request to add an option to xfdesktop to not create -any- backdrop (neither image or solid color), for use with window managers such as Compiz which provide their own screen backgrounds.

Specifically:
   Rename the current "none" option as "solid color"
   Add a new option "none" which really does not create any backdrop at all.

BACKGROUND (no pun intended):

Compiz allows different backgrounds for each viewport (e.g. each side of the cube), but this feature is ineffective with xfce because xfdesktop can not be told to not create a backdrop [I'm guessing that it creates an opaque window over the screen, masking Compiz's backgrounds].   

Currently the only work-around is to permanently disable xfdesktop running.  That allows Compiz's backgrounds to show, but you loose desktop icons such as for removable drives.   Adding a "no backdrop at all" option to xfdesktop would let it play nicely with compiz.