diff --git a/core/dropdowndiv.js b/core/dropdowndiv.js
index b624b3448..c7cb54ba3 100644
--- a/core/dropdowndiv.js
+++ b/core/dropdowndiv.js
@@ -139,6 +139,8 @@ Blockly.DropDownDiv.createDom = function() {
   div.appendChild(arrow);
   Blockly.DropDownDiv.arrow_ = arrow;
 
+  Blockly.DropDownDiv.DIV_.style.opacity = 0;
+
   // Transition animation for transform: translate() and opacity.
   Blockly.DropDownDiv.DIV_.style.transition = 'transform ' +
     Blockly.DropDownDiv.ANIMATION_TIME + 's, ' +