<html contenteditable="true" xmlns="http://www.w3.org/1999/xhtml"><head><script> function boom() { document.execCommand("selectAll", false, ""); try { document.execCommand("justifyfull", false, null); } catch(e) { } try { document.execCommand("inserthorizontalrule", false, "false"); } catch(e) { } document.execCommand("delete", false, null); } </script></head>x y z<body onload="boom();"><div/></body></html>