title: How to login in Puppeteer?
body: <p>I'm new to JavaScript and Puppeteer.
  I tried the login code below, but it failed.
  In comparison, I added <code>page2</code> and succeeded.
  How can I solve it?</p>
  
  <pre><code>const CREDS = require('./creds');
  
  async function main() {
    const puppeteer = require('puppeteer');
    const browser = await puppeteer.launch({headless: false});
  
    const page = await browser.newPage();
    await page.setViewport({width: 1200, height: 720})
    await page.goto('https://www.daum.net');
    await page.waitForNavigation();
    await page.type('#id', CREDS.username);
    await page.type('#loginPw', CREDS.password);
    await page.click('#loginSubmit');
  
    const page2 = await browser.newPage();
    await page2.setViewport({width: 1200, height: 720})
    await page2.goto('https://google.com');
    await page2.type('#lst-ib', 'Headless Chrome');
  }
  
  main();
  </code></pre>