--- a/testing/marionette/element.js
+++ b/testing/marionette/element.js
@@ -100,17 +100,16 @@ element.Strategy = {
  * and may be queried by their web element reference using {@link get()}.
  *
  * @class
  * @memberof element
  */
 element.Store = class {
   constructor() {
     this.els = {};
-    this.timer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
   }
 
   clear() {
     this.els = {};
   }
 
   /**
    * Make a collection of elements seen.