<html>
<meta http-equiv="Delegate-CH" content="dpr https://foo.com/; sec-ch-dpr https://foo.com/; device-memory https://foo.com/; sec-ch-device-memory https://foo.com/; viewport-width https://foo.com/; sec-ch-viewport-width https://foo.com/; rtt https://foo.com/; downlink https://foo.com/; ect https://foo.com/; sec-ch-ua-arch https://foo.com/; sec-ch-ua-platform-version https://foo.com/; sec-ch-ua-model https://foo.com/; sec-ch-ua-full-version https://foo.com/; sec-ch-prefers-color-scheme https://foo.com/; sec-ch-prefers-reduced-motion https://foo.com/; sec-ch-ua-bitness https://foo.com/; sec-ch-viewport-height https://foo.com/; sec-ch-ua-full-version-list https://foo.com/; sec-ch-ua-wow64 https://foo.com/; sec-ch-ua-form-factors https://foo.com/; sec-ch-prefers-reduced-transparency https://foo.com/">
<link rel="icon" href="data:;base64,=">
<body>
<img src="test_img.jpg"></img>
<img src="https://foo.com/non-existing-image.jpg"></img>
<iframe src="https://foo.com/non-existing-iframe.html"></iframe>
<script type="text/javascript">
document.body.innerHTML += '<img src="test_img.jpg?foo"></img>';
document.body.innerHTML += '<img src="https://bar.com/non-existing-image.jpg"></img>';
document.body.innerHTML += '<iframe src="https://bar.com/non-existing-iframe.html"></iframe>';
</script>
</body>
</html>