diff --git a/content/xul/document/public/nsIXULPrototypeCache.h b/content/xul/document/public/nsIXULPrototypeCache.h
index ef516407137..044a1fe6ac8 100644
--- a/content/xul/document/public/nsIXULPrototypeCache.h
+++ b/content/xul/document/public/nsIXULPrototypeCache.h
@@ -129,7 +129,7 @@ const char XUL_FASTLOAD_FILE_BASENAME[] = "XUL";
 // Increase the subtractor when changing version, say when changing the
 // (opaque to FastLoad code) format of JS script, function, regexp, etc.
 // XDR serializations.
-#define XUL_FASTLOAD_FILE_VERSION       (0xfeedbeef - 14)
+#define XUL_FASTLOAD_FILE_VERSION       (0xfeedbeef - 15)
 
 #define XUL_SERIALIZATION_BUFFER_SIZE   (64 * 1024)
 #define XUL_DESERIALIZATION_BUFFER_SIZE (8 * 1024)