<!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 add the 'open' attribute to details1 // element, but Firefox does add 'open' to details1 since summary2 had been // moved to details1 before receiving the 'click' event. var details1 = document.getElementById("details1"); var summary2 = document.getElementById("summary2"); document.body.addEventListener("click", function () { // Move summary2 into details1 at capture phase, and summary2 will be the // main summary of details1 at target phase. details1.insertBefore(summary2, details1.children[0]); }, true); summary2.dispatchEvent(new MouseEvent("click")); document.documentElement.removeAttribute("class"); } </script> <body onload="runTest();"> <details id="details1"> <summary id="summary1">Summary 1</summary> <p>This is the details 1.</p> </details> <details> <summary id="summary2">Summary 2</summary> <p>This is the details 2.</p> </details> </body> </html>