To prevent YouTube to change the video quality automatically during YouTube Live Streaming.
Version au
// ==UserScript==
// @name YouTube: Force html5_exponential_memory_for_sticky
// @namespace Violentmonkey Scripts
// @match https://www.youtube.com/*
// @version 0.2.3
// @license MIT
// @author CY Fung
// @icon https://github.com/cyfung1031/userscript-supports/raw/main/icons/yt-engine.png
// @description To prevent YouTube to change the video quality automatically during YouTube Live Streaming.
// @run-at document-start
// @grant none
// @unwrap
// @allFrames true
// @inject-into page
// ==/UserScript==
// html5_exponential_memory_for_sticky
/* "YouTube to change the video quality automatically during YouTube Live Streaming" refers to the following code:
k_=function(a){if(a.Tf){var b=a.Zi;var c=a.Tf;a=a.Dv();if(b.va.qt().isInline())var d=gO;else b.N("html5_exponential_memory_for_sticky")?d=.5>Jwa(b.Z.Wf,"sticky-lifetime")?"auto":TH[xL()]:d=TH[xL()],d=g.RH("auto",d,!1,"s");if(SH(d)){d=n_a(b,c);var e=d.compose,f;a:if((f=c.j)&&f.videoInfos.length){for(var h=g.u(f.videoInfos),l=h.next();!l.done;l=h.next()){l=l.value;var m=void 0;if(null==(m=l.u)?0:m.smooth){f=l.video.j;break a}}f=f.videoInfos[0].video.j}else f=0;Tma()&&!g.MM(b.Z)&&hI(c.j.videoInfos[0])&&
(f=Math.min(f,g.QH.large));d=e.call(d,new PH(0,f,!1,"o"));e=d.compose;f=4320;!b.Z.u||g.FM(b.Z)||b.Z.N("hls_for_vod")||b.Z.N("mweb_remove_360p_cap")||(f=g.QH.medium);(h=g.AL(b.Z.experiments,"html5_default_quality_cap"))&&c.j.j&&!c.videoData.aj&&!c.videoData.me&&(f=Math.min(f,h));h=g.AL(b.Z.experiments,"html5_random_playback_cap");l=/[a-h]$/;h&&l.test(c.videoData.clientPlaybackNonce)&&(f=Math.min(f,h));if(l=h=g.AL(b.Z.experiments,"html5_hfr_quality_cap"))a:{l=c.j;if(l.j)for(l=g.u(l.videoInfos),m=l.next();!m.done;m=
l.next())if(32<m.value.video.fps){l=!0;break a}l=!1}l&&(f=Math.min(f,h));(h=g.AL(b.Z.experiments,"html5_live_quality_cap"))&&c.videoData.isLivePlayback&&(f=Math.min(f,h));f=A_a(b,c,f);d=e.call(d,new PH(0,4320===f?0:f,!1,"d")).compose(z_a(b)).compose(B_a(b,c.videoData,c)).compose(y_a(b,c)).compose(q_a(b,c));SH(a)&&(d=d.compose(r_a(b,c)))}else b.N("html5_perf_cap_override_sticky")&&(d=d.compose(y_a(b,c))),b.N("html5_ustreamer_cap_override_sticky")&&(d=d.compose(r_a(b,c)));d=d.compose(q_a(b,c));b=c.videoData.Yx.compose(d).compose(c.videoData.lT).compose(a)}else b=
gO;return b};
*/
((__CONTEXT__) => {
const win = this instanceof Window ? this : window;
// Create a unique key for the script and check if it is already running
const hkey_script = 'ezinmgkfbpgh';
if (win[hkey_script]) throw new Error('Duplicated Userscript Calling'); // avoid duplicated scripting
win[hkey_script] = true;
/** @type {globalThis.PromiseConstructor} */
const Promise = ((async () => { })()).constructor;
let isMainWindow = false;
try {
isMainWindow = window.document === window.top.document
} catch (e) { }
const hLooper = ((fn) => {
let nativeFnLoaded = false;
let kc1 = 0;
const setIntervalW = setInterval;
const clearIntervalW = clearInterval;
let microDisconnectFn = null;
let fStopLooper = false;
const looperFn = () => {
if (fStopLooper) return;
let obj = null;
try {
obj = ytcfg.data_.WEB_PLAYER_CONTEXT_CONFIGS.WEB_PLAYER_CONTEXT_CONFIG_ID_KEVLAR_WATCH;
} catch (e) { }
if (obj) {
fn(obj);
if (microDisconnectFn) {
let isYtLoaded = false;
try {
isYtLoaded = typeof ytcfg.set === 'function';
} catch (e) { }
if (isYtLoaded) {
microDisconnectFn();
}
}
}
};
const controller = {
start() {
kc1 = setIntervalW(looperFn, 1);
(async () => {
while (true && !nativeFnLoaded) {
looperFn();
if (fStopLooper) break;
await (new Promise(requestAnimationFrame));
}
})();
looperFn();
},
setupForCleanContext(__CONTEXT__) {
const { requestAnimationFrame, setInterval, clearInterval, setTimeout, clearTimeout } = __CONTEXT__;
(async () => {
while (true) {
looperFn();
if (fStopLooper) break;
await (new Promise(requestAnimationFrame));
}
})();
let kc2 = setInterval(looperFn, 1);
const marcoDisconnectFn = () => {
if (fStopLooper) return;
Promise.resolve().then(() => {
if (kc1 || kc2) {
kc1 && clearIntervalW(kc1); kc1 = 0;
kc2 && clearInterval(kc2); kc2 = 0;
looperFn();
}
fStopLooper = true;
});
document.removeEventListener('yt-page-data-fetched', marcoDisconnectFn, false);
document.removeEventListener('yt-navigate-finish', marcoDisconnectFn, false);
document.removeEventListener('spfdone', marcoDisconnectFn, false);
};
document.addEventListener('yt-page-data-fetched', marcoDisconnectFn, false);
document.addEventListener('yt-navigate-finish', marcoDisconnectFn, false);
document.addEventListener('spfdone', marcoDisconnectFn, false);
function onReady() {
if (!fStopLooper) {
setTimeout(() => {
!fStopLooper && marcoDisconnectFn();
}, 1000);
}
}
Promise.resolve().then(() => {
if (document.readyState !== 'loading') {
onReady();
} else {
window.addEventListener("DOMContentLoaded", onReady, false);
}
});
nativeFnLoaded = true;
microDisconnectFn = () => Promise.resolve(marcoDisconnectFn).then(setTimeout);
}
};
return controller;
})((obj) => {
if (typeof obj.serializedExperimentFlags === 'string') {
if (obj.serializedExperimentFlags.indexOf('&h5_expr_b9Nkc=true') > 0) return;
obj.serializedExperimentFlags = obj.serializedExperimentFlags.replace(/(^|&)html5_exponential_memory_for_sticky=\w+/, '') + '&html5_exponential_memory_for_sticky=true&h5_expr_b9Nkc=true';
}
});
hLooper.start();
const cleanContext = async (win) => {
const waitFn = requestAnimationFrame; // shall have been binded to window
try {
let mx = 16; // MAX TRIAL
const frameId = 'vanillajs-iframe-v1'
let frame = document.getElementById(frameId);
let removeIframeFn = null;
if (!frame) {
frame = document.createElement('iframe');
frame.id = frameId;
const blobURL = typeof webkitCancelAnimationFrame === 'function' ? (frame.src = URL.createObjectURL(new Blob([], { type: 'text/html' }))) : null; // avoid Brave Crash
frame.sandbox = 'allow-same-origin'; // script cannot be run inside iframe but API can be obtained from iframe
let n = document.createElement('noscript'); // wrap into NOSCRPIT to avoid reflow (layouting)
n.appendChild(frame);
while (!document.documentElement && mx-- > 0) await new Promise(waitFn); // requestAnimationFrame here could get modified by YouTube engine
const root = document.documentElement;
root.appendChild(n); // throw error if root is null due to exceeding MAX TRIAL
if (blobURL) Promise.resolve().then(() => URL.revokeObjectURL(blobURL));
removeIframeFn = (setTimeout) => {
const removeIframeOnDocumentReady = (e) => {
e && win.removeEventListener("DOMContentLoaded", removeIframeOnDocumentReady, false);
win = null;
const m = n;
n = null;
setTimeout(() => m.remove(), 200);
}
if (document.readyState !== 'loading') {
removeIframeOnDocumentReady();
} else {
win.addEventListener("DOMContentLoaded", removeIframeOnDocumentReady, false);
}
}
}
while (!frame.contentWindow && mx-- > 0) await new Promise(waitFn);
const fc = frame.contentWindow;
if (!fc) throw "window is not found."; // throw error if root is null due to exceeding MAX TRIAL
const { requestAnimationFrame, setInterval, setTimeout, clearInterval, clearTimeout } = fc;
const res = { requestAnimationFrame, setInterval, setTimeout, clearInterval, clearTimeout };
for (let k in res) res[k] = res[k].bind(win); // necessary
if (removeIframeFn) Promise.resolve(res.setTimeout).then(removeIframeFn);
return res;
} catch (e) {
console.warn(e);
return null;
}
};
cleanContext(win).then(__CONTEXT__ => {
const { requestAnimationFrame, setInterval, clearInterval, setTimeout, clearTimeout } = __CONTEXT__;
hLooper.setupForCleanContext(__CONTEXT__)
});
})(null);