puppeteer.captcha.js

const puppeteer = require("puppeteer");

(async () => {
  const browser = await puppeteer.launch({
    headless: false,
    defaultViewport: false
  });
  const page = (await browser.pages())[0];
  // imaginary page with a captcha on it
  await page.goto(
    "https://example.com/captcha-page", 
    { waitUntil: "load" }
  );

  const elementHandler = await page.$("#captcha-container img");
  // base64String contains the captcha image's base64 encoded version
  const base64String = await elementHandler.screenshot({ encoding: "base64" });
})();