<!DOCTYPE html> <meta charset="utf-8"> <script src="/tests/SimpleTest/SimpleTest.js"></script> <div id="div"> <script> /* globals div svgRanScript */ SimpleTest.waitForExplicitFinish(); window.svgRanScript = false; const o = new MutationObserver(mutations => { o.disconnect(); setTimeout(() => { ok(!svgRanScript, "svg onload must not fire"); SimpleTest.finish(); }); }); o.observe(div, {childList: true}); const p = (new DOMParser()).parseFromString("<svg onload=\"window.svgRanScript=true\"></svg>", "text/html"); div.appendChild(p.body); </script>