<Html class="reftest-wait"> <head> <meta http-equiv="content-type" content="text/html; charset=utf8"> </head> <body onload="boom()"> <iframe src="#" id="data"></iframe> <script> function boom() { var d=document.getElementById('data').contentDocument; d.clear() var text='Тест'; d.write(text); d.close(); document.documentElement.removeAttribute("class"); } </script> </body> </html>