Puppeteer NOT working with Firefox (nightly) when {product: 'firefox'}

Steps to reproduce

1. Download Firefox Nightly
2. Run the below edited example to use product: 'firefox'

/**
 * @name Duck Duck Go search
 */

const puppeteer = require('puppeteer');

(async () => {
  const browser = await puppeteer.launch({
	  headless: false,
	  product: 'firefox',
	  //executablePath: 'C:/Program Files (x86)/Google/Chrome/Application/chrome.exe'
	  //executablePath: 'C:/Program Files/Mozilla Firefox/firefox.exe'
	  executablePath: 'C:/Program Files/Firefox Developer Edition/firefox.exe',
	  dumpio: true

	  });
  const page = await browser.newPage()
  await page.goto('https://duckduckgo.com/')  
  await page.type('#search_form_input_homepage', 'Puppeteer')
  const searchValue = await page.$eval('#search_form_input_homepage', el => el.value)
  console.log(searchValue)
  await browser.close()
})()

Tell us about your environment:

• Puppeteer version: 3.2.0
• Platform / OS version: Windows 10
• URLs (if applicable):
• Node.js version: v13.8.0
• NPM version: 6.14.2

What steps will reproduce the problem? Described above

What is the expected result? Puppeteer to work as expected, the same way (or near) as it works with chrome/chromium

What happens instead? It crash with:

C:\Users\Milen\Desktop\Puppeteer-Test_Firefox>node test.js
(node:12256) UnhandledPromiseRejectionWarning: Error: Failed to launch the browser process!


TROUBLESHOOTING: https://github.com/puppeteer/puppeteer/blob/master/docs/troubleshooting.md

    at onClose (C:\Users\Milen\Desktop\Puppeteer-Test_Firefox\node_modules\puppeteer\lib\Launcher.js:750:14)
    at ChildProcess.<anonymous> (C:\Users\Milen\Desktop\Puppeteer-Test_Firefox\node_modules\puppeteer\lib\Launcher.js:740:61)
    at ChildProcess.emit (events.js:333:22)
    at Process.ChildProcess._handle.onexit (internal/child_process.js:275:12)
(node:12256) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
(node:12256) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
[Error: EBUSY: resource busy or locked, unlink 'C:\Users\Milen\AppData\Local\Temp\puppeteer_dev_firefox_profile-BFNrfA\cookies.sqlite'] {
  errno: -4082,
  code: 'EBUSY',
  syscall: 'unlink',
  path: 'C:\\Users\\Milen\\AppData\\Local\\Temp\\puppeteer_dev_firefox_profile-BFNrfA\\cookies.sqlite'
}

and the Firefox Nightly is left open: About was additionali clicked in order to see the version.

Can you please someone review it and advise what might be the issue.

Thank you,

Milen Palavrov

[mpalavrov]

Just for whoever is having this issue. The fix for my troubles are…:

/**
 * @name Duck Duck Go search
 */

const puppeteer = require('puppeteer-core');

(async () => {
  const browser = await puppeteer.launch({
	  headless: true,
	  product: 'firefox',
	  args: [
	  '-wait-for-browser'
	  ],
	  executablePath: 'C:/Program Files/Firefox Nightly/firefox.exe',
		userDataDir: 'C:/Users/Milen/Desktop/Puppeteer-Test_Firefox/Profile_FirefoxNightly',
	  });

  const page = await browser.newPage()
  	
  //await page.goto('https://duckduckgo.com/')  
      await page.setViewport({ width: 1920, height: 1080 });
   await page.screenshot({path: 'example.png'});
  await browser.close()
})()

There were 2 issues with my code:

1. I was using Firefox Developers 🔴 instead of Firefox Nightly 🟢 , which seems to be an issue.
2. I have added

	  args: [
	  '-wait-for-browser'
	  ],

Which seems to be needed when using Firefox.

Cheers guys, I hope it helps someone.

Closing.

[mjzffr]

Thanks for sharing your solution 😃