diff --git a/kis-all.js b/kis-all.js
index f9e0cbc..afe9a0b 100644
--- a/kis-all.js
+++ b/kis-all.js
@@ -1091,6 +1091,8 @@ if (typeof document !== "undefined" && !("classList" in document.createElement("
  */
 (function (){
 
+	"use strict";
+
 	// Property name for expandos on DOM objects
 	var kis_expando = "KIS_0_3_0";