From 6d7d636e779f0e90163198f1ef643fb435df6e14 Mon Sep 17 00:00:00 2001
From: Marrion Lulu <marrion91300@gmail.com>
Date: Thu, 21 Sep 2023 13:50:03 -0700
Subject: [PATCH] Fixing channel messaging type error

---
 channel-messaging-basic/page2.html | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/channel-messaging-basic/page2.html b/channel-messaging-basic/page2.html
index 3929fec5..195ed6a0 100644
--- a/channel-messaging-basic/page2.html
+++ b/channel-messaging-basic/page2.html
@@ -14,6 +14,8 @@
       window.addEventListener("message", onMessage);
 
       function onMessage(e) {
+        if (!e.ports.length) return;
+
         output.innerHTML = e.data;
         // Use the transfered port to post a message back to the main frame
         e.ports[0].postMessage("Message back from the IFrame");