From 7c0d9a8c5a40833649db82c80805e3b4dd050c23 Mon Sep 17 00:00:00 2001
From: alschmiedt <aschmiedt@google.com>
Date: Tue, 11 Jan 2022 15:48:36 -0800
Subject: [PATCH] fix: Adds check for changedTouches

---
 core/touch.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/core/touch.js b/core/touch.js
index b977d05af2c..c4d92a221c8 100644
--- a/core/touch.js
+++ b/core/touch.js
@@ -212,7 +212,7 @@ exports.checkTouchIdentifier = checkTouchIdentifier;
  * @alias Blockly.Touch.setClientFromTouch
  */
 const setClientFromTouch = function(e) {
-  if (utilsString.startsWith(e.type, 'touch')) {
+  if (utilsString.startsWith(e.type, 'touch') && e.changedTouches) {
     // Map the touch event's properties to the event.
     const touchPoint = e.changedTouches[0];
     e.clientX = touchPoint.clientX;