File xfdesktop-default-background-image.patch of Package xfdesktop
Index: xfdesktop-4.9.3/common/xfdesktop-common.h
===================================================================
--- xfdesktop-4.9.3.orig/common/xfdesktop-common.h
+++ xfdesktop-4.9.3/common/xfdesktop-common.h
@@ -32,7 +32,7 @@
#include <X11/Xlib.h>
#define XFDESKTOP_CHANNEL "xfce4-desktop"
-#define DEFAULT_BACKDROP DATADIR "/backgrounds/xfce/xfce-blue.jpg"
+#define DEFAULT_BACKDROP DATADIR "/wallpapers/xfce/default.wallpaper"
#define DEFAULT_BACKDROP_LIST "xfce4/desktop/backdrop.list"
#define DEFAULT_ICON_FONT_SIZE 12
#define DEFAULT_ICON_SIZE 32