<!DOCTYPE html> <html class="reftest-wait"> <head> <style type="text/css"> body { margin: 0; } #block { background-color: green; margin: 10px 0; } #inline-block { display: block; margin: 10px 0; background-color: lightgreen; } </style> <script type="text/javascript"> function test() { document.getElementById('inline-block').style.display = 'inline-block'; document.documentElement.removeAttribute('class'); } document.addEventListener('MozReftestInvalidate', test, false); </script> </head> <body> <div id="block"><div id="inline-block">Hello Kitty</div></div> </body> </html>