Source code
Revision control
Copy as Markdown
Other Tools
<!DOCTYPE html>
<a href="file_use_counter_bfcache_helper.html?b">b</a>
<a href="file_use_counter_bfcache_helper.html?c">c</a>
<svg></svg>
<script>
let which = location.search.substring(1);
if (which == "c") {
// Set the sentinel use counter.
let s = document.createElement("style");
s.textContent = "g { marker-mid: none; }";
document.body.append(s);
}
onload = function() {
window.opener.postMessage(`${which}-doc-loaded`, "*");
};
onmessage = function() {
switch (event.data) {
case "click-b-link":
document.querySelectorAll("a")[0].click();
break;
case "click-c-link":
document.querySelectorAll("a")[1].click();
break;
case "go-back":
history.back();
break;
case "set-use-counter":
document.querySelector("svg").getElementById("x");
window.opener.postMessage("did-set-use-counter", "*");
break;
}
};
onpageshow = function() {
window.opener.postMessage(`${which}-doc-shown`, "*");
};
</script>