worker_fetch.js

# https://github.com/uBlockOrigin/uAssets/pull/3517
twitch-videoad.js application/javascript
(function() {   
    if ( /(^|\.)twitch\.tv$/.test(document.location.hostname) === false ) { return; }
    // m3u8 segment stripper by instance01 (https://github.com/instance01/Twitch-HLS-AdBlock)
    const SUPPORTED_VERSION = "2.9.2";
    const oldWorker = window.Worker;
    window.Worker = class Worker extends oldWorker {
        constructor(twitchBlobUrl) {
            var version = getWasmBinaryVersion(twitchBlobUrl);
            var usePerformanceFix = true;
            if (version != SUPPORTED_VERSION) {
                console.log(`Twitch HLS Adblock found possibly unsupported version: ${version}.`);
                console.log(`Current supported version: ${SUPPORTED_VERSION}.`);
                console.log("This is most likely fine. Trying upstream wasmworker..");
                usePerformanceFix = false;
            }
            var functions = getFuncsForInjection_FectTest(usePerformanceFix);
            var newBlobStr = `
                var Module = {
                    WASM_BINARY_URL: 'https://cvp.twitch.tv/${version}/wasmworker.min.wasm',
                    WASM_CACHE_MODE: true
                }
                ${ functions }
                importScripts('https://cvp.twitch.tv/${version}/wasmworker.min.js');
            `
            super(URL.createObjectURL(new Blob([newBlobStr])));
        }
    }
    function getWasmBinaryVersion (twitchBlobUrl) {
        var req = new XMLHttpRequest();
        req.open('GET', twitchBlobUrl, false);
        req.send();
        return req.responseText.match(/tv\/(.*)\/wasmworker/)[1];
    }
    function getFuncsForInjection_FectTest (usePerformanceFix) {
        return `${fetchTest.toString()}fetchTest();`;
    }
    function fetchTest() {
        // This is a simple test using a proxy server to process the m3u8 response
        var realFetch = fetch;
        fetch = function(input, init) {
            if (typeof input === 'string' && input.includes('/playlist/') && input.includes('.m3u8')) {
                arguments[0] = 'http://localhost/TwitchTest?data=' + btoa(arguments[0]);
                //console.log('redirect url ' + arguments[0]);
            }
            return realFetch.apply(this, arguments);
        }
    }
})();