A Discord login workaround that failed but contains many valuable knowledge I guess

discord-workaround-puppeteer-fail.js

const puppeteer = require("puppeteer");

// This works around Discord's security measurements
// to set values on localStorage before we go to discord.com/login
const setDomainLocalStorage = async (browser, url, values) => {
  const page = await browser.newPage();
  await page.setRequestInterception(true);
  page.on("request", r => {
    r.respond({
      status: 200,
      contentType: "text/plain",
      body: "tweak me."
    });
  });
  await page.goto(url);
  await page.evaluate(values => {
    const iframe = document.createElement("iframe");
    iframe.onload = () => {
      // iframes must be appended to the DOM in order to be loaded
      // iframes do not load immediately nor synchronously
      // now (after load) we can use iframe.contentWindow:
      // window.localStorage = iframe.contentWindow.localStorage; // you can use it, but better is like:
      const ifrLocalStorage = iframe.contentWindow.localStorage;
      // But DO NOT: "document.body.removeChild(iframe);" because after it access on 'Storage' will be denied
      Object.keys(values).forEach(key =>
        ifrLocalStorage.setItem(key, values[key])
      );
    };
    iframe.src = "about:blank";
    document.body.appendChild(iframe);
  }, values);
  await page.close();
};

(async () => {
  const browser = await puppeteer.launch();
  await setDomainLocalStorage(browser, "https://discordapp.com/", {fingerprint: "fingerprint"});
  
  const page = await browser.newPage();
  await page.goto("https://discordapp.com/app");

  const localStorageData = await page.evaluate(() => {
    return new Promise(resolve => {
      const iframe = document.createElement("iframe");
      iframe.onload = () => {
        const ifrLocalStorage = iframe.contentWindow.localStorage;
        const json = {};
        for (let i = 0; i < ifrLocalStorage.length; i++) {
          const key = ifrLocalStorage.key(i);
          json[key] = ifrLocalStorage.getItem(key);
        }
        resolve(json);
      };
      iframe.src = "about:blank";
      document.body.appendChild(iframe);
    });
  });
  
  console.log(localStorageData);

  await page.waitFor(5000);

  // await page.waitForSelector('a[href="/channels/@me"]');

  await page.screenshot({ path: "screenshot.png" });
})();

Another way of accessing localStorage from within page.evaluate actually worked in one of my projects.

Discord encapsulates reference to localStorage object into a closure, and breaks it in a global execution context, so it is not accessible from scripts running within it anymore.

We can actually restrict that by forcibly setting a reference to non-writable. See gist

This is old as heck but here's an updated version I made that works, puppeteer included

https://gist.github.com/listingclown3/7d5ac6e42a0cdc5ce85f28ededa3106b