Ignore Width Changes of the iframe, listen only to width changes.

layouts/scripts/frame-index.js

@@ -1,16 +1,26 @@
 'use strict';
 
+let height = getCurrentHeight();
 setupResizeListener();
 
 ///
 
 function setupResizeListener() {
-  const RESIZE_CODE = 'resize:';
+  const resizeObserver = new ResizeObserver((entries) => setTimeout(handleHeightChange, 100));
+  resizeObserver.observe(document.body);
+}
+
+function handleHeightChange(entries) {
+  const updatedHeight = getCurrentHeight();
+  if (height === updatedHeight) {
+    return;
+  }
 
-  const resizeObserver = new ResizeObserver(entries => {
-    const height = document.querySelector('body > main').scrollHeight;
+  const RESIZE_CODE = 'resize:';
   window.parent.postMessage(RESIZE_CODE + JSON.stringify({height}), '*');
-  })
+  height = updatedHeight;
+}
 
-  resizeObserver.observe(document.body);
+function getCurrentHeight() {
+  return document.querySelector('body > main').scrollHeight;
 }