<!DOCTYPE html>
<body>
<script>
if (window.testRunner)
  testRunner.dumpAsText();

window.onload = function() {
  document.getElementById('results').innerHTML =
    document.getElementsByTagName('img')[0].width + 'x' +
    document.getElementsByTagName('img')[0].height;
}
</script>
<img src="resources/green-313x313.avif">
<div id="results"></div>
</body>