diff --git a/js/src/util.js b/js/src/util.js
index e3e7797931..1fa55494ea 100644
--- a/js/src/util.js
+++ b/js/src/util.js
@@ -22,8 +22,6 @@ const Util = (() => {
 
   const TransitionEndEvent = {
     WebkitTransition : 'webkitTransitionEnd',
-    MozTransition    : 'transitionend',
-    OTransition      : 'oTransitionEnd otransitionend',
     transition       : 'transitionend'
   }