<!DOCTYPE html> <!-- Any copyright is dedicated to the Public Domain. - http://creativecommons.org/publicdomain/zero/1.0/ --> <html class="reftest-wait"> <script> function runTest() { // Both Chrome and Safari do not toggle the 'open' attribute for a <details> // with 'display: none'. var summary = document.getElementById("summary"); summary.dispatchEvent(new MouseEvent("click")); var details = document.getElementById("details"); details.style.display = "block"; document.documentElement.removeAttribute("class"); } </script> <body onload="runTest();"> <details id="details" style="display: none;"> <summary id="summary">Summary</summary> <p>This is the details.</p> </details> </body> </html>