file_use_counter_bfcache_helper.html (986B)
1 <!DOCTYPE html> 2 <a href="file_use_counter_bfcache_helper.html?b">b</a> 3 <a href="file_use_counter_bfcache_helper.html?c">c</a> 4 <svg></svg> 5 <script> 6 let which = location.search.substring(1); 7 8 if (which == "c") { 9 // Set the sentinel use counter. 10 let s = document.createElement("style"); 11 s.textContent = "g { marker-mid: none; }"; 12 document.body.append(s); 13 } 14 15 onload = function() { 16 window.opener.postMessage(`${which}-doc-loaded`, "*"); 17 }; 18 19 onmessage = function() { 20 switch (event.data) { 21 case "click-b-link": 22 document.querySelectorAll("a")[0].click(); 23 break; 24 case "click-c-link": 25 document.querySelectorAll("a")[1].click(); 26 break; 27 case "go-back": 28 history.back(); 29 break; 30 case "set-use-counter": 31 document.querySelector("svg").getElementById("x"); 32 window.opener.postMessage("did-set-use-counter", "*"); 33 break; 34 } 35 }; 36 37 onpageshow = function() { 38 window.opener.postMessage(`${which}-doc-shown`, "*"); 39 }; 40 </script>