<html class="reftest-wait"> <head> <script type="text/javascript"> function addUnderline() { var element = document.getElementById("dynamicUnderline"); element.style.textDecoration = "underline"; document.documentElement.removeAttribute("class"); } document.addEventListener('MozReftestInvalidate', addUnderline); </script> <style> .align-bottom { vertical-align: bottom; } .align-top { vertical-align: top; } </style> </head> <body> <p id="dynamicUnderline"> <span class="align-bottom">This</span> line has a bottom vertical align span. <br /> <span class="align-top">This</span> line has a top vertical align span. </p> </body> </html>