nav-cancelation-2-helper.html (545B)
1 <!DOCTYPE html> 2 <meta charset="utf-8"> 3 <title>Page with child frame that navigates slowly</title> 4 5 <!-- 6 This file is used by `../nav-cancelation-2.sub.html`. The iframe below is its 7 grandchild iframe, and whenever its load event fires we report this up to our 8 parent Document. 9 --> 10 <iframe src="slow.py"></iframe> 11 12 <script> 13 window.parent.postMessage("grandchild frame created", "*"); 14 const iframe = document.querySelector('iframe'); 15 iframe.onload = e => { 16 window.parent.postMessage("grandchild frame loaded", "*"); 17 }; 18 </script>