<body> <script> if (window.testRunner) testRunner.dumpAsText(); window.addEventListener('DOMContentLoaded', function() { if (window.internals) console.log(internals.isPreloaded("resources/link1.css") ? "PASS" : "FAIL"); }, false); </script> This test requires DumpRenderTree to see the log of what resources are loaded. <script src=resources/non-existant.js></script> <script>document.write("<plaintext>");</script> <link href=resources/link1.css rel="stylesheet">