File xfdesktop-default-background-image.patch of Package xfdesktop
Index: xfdesktop-4.12.0/common/xfdesktop-common.h
===================================================================
--- xfdesktop-4.12.0.orig/common/xfdesktop-common.h
+++ xfdesktop-4.12.0/common/xfdesktop-common.h
@@ -35,7 +35,7 @@
#include <stdarg.h>
#define XFDESKTOP_CHANNEL "xfce4-desktop"
-#define DEFAULT_BACKDROP DATADIR "/backgrounds/xfce/xfce-teal.jpg"
+#define DEFAULT_BACKDROP DATADIR "/wallpapers/xfce/default.wallpaper"
#define DEFAULT_ICON_FONT_SIZE 12
#define DEFAULT_ICON_SIZE 48
#define ITHEME_FLAGS (GTK_ICON_LOOKUP_USE_BUILTIN \