Can Selenium WebDriver open browser windows silently in the background?

Question

If you are using Selenium web driver with Python, you can use PyVirtualDisplay, a Python wrapper for Xvfb and Xephyr.

PyVirtualDisplay needs Xvfb as a dependency. On Ubuntu, first install Xvfb:

sudo apt-get install xvfb

Then install PyVirtualDisplay from PyPI:

pip install pyvirtualdisplay

Sample Selenium script in Python in a headless mode with PyVirtualDisplay:

    #!/usr/bin/env python

    from pyvirtualdisplay import Display
    from selenium import webdriver

    display = Display(visible=0, size=(800, 600))
    display.start()

    # Now Firefox will run in a virtual display.
    # You will not see the browser.
    browser = webdriver.Firefox()
    browser.get('http://www.google.com')
    print browser.title
    browser.quit()

    display.stop()

EDIT

The initial answer was posted in 2014 and now we are at the cusp of 2018. Like everything else, browsers have also advanced. Chrome has a completely headless version now which eliminates the need to use any third-party libraries to hide the UI window. Sample code is as follows:

    from selenium import webdriver
    from selenium.webdriver.chrome.options import Options

    CHROME_PATH = '/usr/bin/google-chrome'
    CHROMEDRIVER_PATH = '/usr/bin/chromedriver'
    WINDOW_SIZE = "1920,1080"

    chrome_options = Options()
    chrome_options.add_argument("--headless")
    chrome_options.add_argument("--window-size=%s" % WINDOW_SIZE)
    chrome_options.binary_location = CHROME_PATH

    driver = webdriver.Chrome(executable_path=CHROMEDRIVER_PATH,
                              chrome_options=chrome_options
                             )
    driver.get("https://www.google.com")
    driver.get_screenshot_as_file("capture.png")
    driver.close()

There are a few ways, but it isn't a simple "set a configuration value". Unless you invest in a headless browser, which doesn't suit everyone's requirements, it is a little bit of a hack:

How to hide Firefox window (Selenium WebDriver)?

and

Is it possible to hide the browser in Selenium RC?

You can 'supposedly', pass in some parameters into Chrome, specifically: --no-startup-window

Note that for some browsers, especially Internet Explorer, it will hurt your tests to not have it run in focus.

You can also hack about a bit with AutoIt, to hide the window once it's opened.

Chrome 57 has an option to pass the --headless flag, which makes the window invisible.

This flag is different from the --no-startup-window as the last doesn't launch a window. It is used for hosting background apps, as this page says.

Java code to pass the flag to Selenium webdriver (ChromeDriver):

ChromeOptions options = new ChromeOptions();
options.addArguments("--headless");
ChromeDriver chromeDriver = new ChromeDriver(options);

For running without any browser, you can run it in headless mode.

I show you one example in Python that is working for me right now

from selenium import webdriver


options = webdriver.ChromeOptions()
options.add_argument("headless")
self.driver = webdriver.Chrome(executable_path='/Users/${userName}/Drivers/chromedriver', chrome_options=options)

I also add you a bit more of info about this in the official Google website https://developers.google.com/web/updates/2017/04/headless-chrome

Since Chrome 57 you have the headless argument:

var options = new ChromeOptions();
options.AddArguments("headless");
using (IWebDriver driver = new ChromeDriver(options))
{
    // The rest of your tests
}

The headless mode of Chrome performs 30.97% better than the UI version. The other headless driver PhantomJS delivers 34.92% better than the Chrome's headless mode.

PhantomJSDriver

using (IWebDriver driver = new PhantomJSDriver())
{
     // The rest of your test
}

The headless mode of Mozilla Firefox performs 3.68% better than the UI version. This is a disappointment since the Chrome's headless mode achieves > 30% better time than the UI one. The other headless driver PhantomJS delivers 34.92% better than the Chrome's headless mode. Surprisingly for me, the Edge browser beats all of them.

var options = new FirefoxOptions();
options.AddArguments("--headless");
{
    // The rest of your test
}

This is available from Firefox 57+

The headless mode of Mozilla Firefox performs 3.68% better than the UI version. This is a disappointment since the Chrome's headless mode achieves > 30% better time than the UI one. The other headless driver PhantomJS delivers 34.92% better than the Chrome's headless mode. Surprisingly for me, the Edge browser beats all of them.

Note: PhantomJS is not maintained any more!

I used this code for Firefox in Windows and got answer(reference here):

from selenium import webdriver
from selenium.webdriver.firefox.options import Options

Options = Options()
Options.headless = True

Driver = webdriver.Firefox(options=Options, executable_path='geckodriver.exe')
Driver.get(...)
...

But I didn't test it for other browsers.