<!DOCTYPE html> <html class="reftest-wait"> <head> <meta charset="UTF-8"> <script> function f() { function spin() { for (var i = 0; i < 8; ++i) { var x = new XMLHttpRequest(); x.open('GET', 'data:text/html,' + i, false); x.send(); } } window.addEventListener("popstate", spin, false); window.close(); window.location = "#c"; finish(); } function init() { SpecialPowers.pushPrefEnv({"set": [ ["security.data_uri.block_toplevel_data_uri_navigations", false], ]}, start); } function start() { var html = "<script>" + f + "<\/script><body onload=f()>"; var win = window.open("data:text/html," + encodeURIComponent(html), null, "width=300,height=300"); win.finish = function() { document.documentElement.removeAttribute("class"); }; } </script> </head> <body onload="init();"></body> </html>