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var callback = arguments[arguments.length - 1];
var observer = null;
var root = document.documentElement;
function wait_load() {
if (Document.prototype.hasOwnProperty("fonts")) {
document.fonts.ready.then(wait_paints);
} else {
// This might take the screenshot too early, depending on whether the
// load event is blocked on fonts being loaded. See:
wait_paints();
}
}
function wait_paints() {
// As of 2017-04-05, the Chromium web browser exhibits a rendering bug
// produces instability during screen capture. The following use of
// `requestAnimationFrame` is intended as a short-term workaround, though
// it is not guaranteed to resolve the issue.
//
// For further detail, see:
requestAnimationFrame(function() {
requestAnimationFrame(function() {
screenshot_if_ready();
});
});
}
function screenshot_if_ready() {
if (root &&
root.classList.contains("%(classname)s") &&
observer === null) {
observer = new MutationObserver(wait_paints);
observer.observe(root, {attributes: true});
var event = new Event("TestRendered", {bubbles: true});
root.dispatchEvent(event);
return;
}
if (observer !== null) {
observer.disconnect();
}
callback();
}
if (document.readyState != "complete") {
addEventListener('load', wait_load);
} else {
wait_load();
}