diff --git a/dom/plugins/base/npapi.h b/dom/plugins/base/npapi.h
index 38b296c63d..aa6a66b2bd 100644
--- a/dom/plugins/base/npapi.h
+++ b/dom/plugins/base/npapi.h
@@ -46,7 +46,6 @@
 #if defined(MOZ_X11)
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
-#include "X11UndefineNone.h"
 #endif
 #endif