chromium/chrome/test/data/ssl/page_with_dynamic_insecure_content.html

<html>
<head><title>Page with dynamic insecure content</title>

<script>
  function loadBadImage() {
    var image = document.getElementById("my_image");
    return new Promise(resolve => {
      image.addEventListener('load', () => {
        document.getElementById("status_text").innerHTML = "Bad image loaded";
        resolve(true);
      });
      image.src = "http://REPLACE_WITH_HOST_AND_PORT/ssl/google_files/logo.gif";
    });
  }
</script>

</head>
<body>

This page has some java-script that loads some insecure content.
<br><br>
You can also press the button below to load the image.
<br>
<input type=button value="Load image" onclick="loadBadImage();"></input>

<div id="status_text">Contents is OK</div>
<img id="my_image" src=""/>


</body>
</html>