<!DOCTYPE html> <html class="reftest-wait"> <head> <style> label {color: red} img:not(:-moz-broken) ~ label {color: green} img { display: none; } </style> </head> <body onload='var i1 = document.getElementById("ffximage"); i1.onload = function() { document.documentElement.className = ""; }; i1.setAttribute("src", "solidblue.png");'> <img src="no-such-scheme:nothing" id="ffximage"/> <label for="ffximage">Text should be green</label> </body> </html>