frame-with-insecure-css-resources.html

<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" href="fetch-insecure-css-resources.css">
</head>
<body>
This background image should be 20px blue square.
<script>
document.fonts.ready.then(function() {
    if (window.opener)
        window.opener.postMessage('done', '*');
});
</script>
</body>
</html>

chromium/third_party/blink/web_tests/http/tests/security/mixedContent/resources/frame-with-insecure-css-resources.html