<!DOCTYPE html> <html class="reftest-wait"> <head> <meta charset="UTF-8"> </head> <body> <!-- Bug 1219068 --> <math style="position:absolute; top: 0; font-size:1em; z-index: 0;" display="block"> <mrow> <mo>|</mo> <mrow> <mi>f</mi> <mrow> <mn>(</mn> <mi>x</mi> <mn>)</mn> </mrow> <mn>-</mn> <mrow> <mi>f</mi> <mrow> <mn>(</mn> <msub> <mi>x</mi> <mn>0</mn> </msub> <mn>)</mn> </mrow> </mrow> </mrow> <mo>|</mo> </mrow> </math> <div id="hider" style="position:absolute; top:0; left:0; background-color:green; height:1em; width:100%; z-index:1; padding-top:5px; padding-bottom:5px; visibility:hidden" /> <script> function obscureMathML() { var hider = document.getElementById("hider"); hider.style.visibility="visible"; // The math should now be completely obscured document.documentElement.removeAttribute("class"); } window.addEventListener("MozReftestInvalidate", obscureMathML, false); </script> </body> </html>