Firefox specific functionality

These are capabilities and features specific to Mozilla Firefox browsers.

Selenium 4 requires Firefox 78 or greater. It is recommended to always use the latest version of geckodriver.

Options

Capabilities common to all browsers are described on the Options page.

Capabilities unique to Firefox can be found at Mozilla’s page for firefoxOptions

Starting a Firefox session with basic defined options looks like this:

    FirefoxOptions options = new FirefoxOptions();
    driver = new FirefoxDriver(options);
    options = webdriver.FirefoxOptions()
    driver = webdriver.Firefox(options=options)
            var options = new FirefoxOptions();
            driver = new FirefoxDriver(options);
      options = Selenium::WebDriver::Options.firefox
      @driver = Selenium::WebDriver.for :firefox, options: options
    driver = new Builder()
      .forBrowser(Browser.FIREFOX)
      .setFirefoxOptions(options)
      .build();

Here are a few common use cases with different capabilities:

Arguments

The args parameter is for a list of Command line switches used when starting the browser.
Commonly used args include -headless and "-profile", "/path/to/profile"

Add an argument to options:

    options.addArguments("-headless");
    options.add_argument("-headless")
            options.AddArgument("-headless");
      options.args << '-headless'
      .setFirefoxOptions(options.addArguments('--headless'))

Start browser in a specified location

The binary parameter takes the path of an alternate location of browser to use. For example, with this parameter you can use geckodriver to drive Firefox Nightly instead of the production version when both are present on your computer.

Add a browser location to options:

    options.setBinary(getFirefoxLocation());
    options.binary_location = firefox_bin
            options.BinaryLocation = GetFirefoxLocation();
      options.binary = firefox_location

Profiles

There are several ways to work with Firefox profiles

    FirefoxProfile profile = new FirefoxProfile();
    FirefoxOptions options = new FirefoxOptions();
    profile.setPreference("javascript.enabled", "False");
    options.setProfile(profile);

    driver = new FirefoxDriver(options);
    from selenium.webdriver.firefox.options import Options
    from selenium.webdriver.firefox.firefox_profile import FirefoxProfile

    options = Options()
    firefox_profile = FirefoxProfile()
    firefox_profile.set_preference("javascript.enabled", False)
    options.profile = firefox_profile

    driver = webdriver.Firefox(options=options)
var options = new FirefoxOptions();
var profile = new FirefoxProfile();
options.Profile = profile;
var driver = new RemoteWebDriver(options);
  
      profile = Selenium::WebDriver::Firefox::Profile.new
          profile['browser.download.dir'] = '/tmp/webdriver-downloads'
          options = Selenium::WebDriver::Firefox::Options.new(profile: profile)
const { Builder } = require("selenium-webdriver");
const firefox = require('selenium-webdriver/firefox');

const options = new firefox.Options();
let profile = '/path to custom profile';
options.setProfile(profile);
const driver = new Builder()
    .forBrowser('firefox')
    .setFirefoxOptions(options)
    .build();
  
val options = FirefoxOptions()
options.profile = FirefoxProfile()
driver = RemoteWebDriver(options)
  

Service

Service settings common to all browsers are described on the Service page.

Log output

Getting driver logs can be helpful for debugging various issues. The Service class lets you direct where the logs will go. Logging output is ignored unless the user directs it somewhere.

File output

To change the logging output to save to a specific file:

    FirefoxDriverService service =
        new GeckoDriverService.Builder().withLogFile(logLocation).build();

Note: Java also allows setting file output by System Property:
Property key: GeckoDriverService.GECKO_DRIVER_LOG_PROPERTY
Property value: String representing path to log file

Selenium v4.11

    service = webdriver.FirefoxService(log_output=log_path, service_args=['--log', 'debug'])

Console output

To change the logging output to display in the console:

Selenium v4.10

    FirefoxDriverService service =
        new GeckoDriverService.Builder().withLogOutput(System.out).build();

Note: Java also allows setting console output by System Property;
Property key: GeckoDriverService.GECKO_DRIVER_LOG_PROPERTY
Property value: DriverService.LOG_STDOUT or DriverService.LOG_STDERR

Selenium v4.11

    service = webdriver.FirefoxService(log_output=subprocess.STDOUT)

Log level

There are 7 available log levels: fatal, error, warn, info, config, debug, trace. If logging is specified the level defaults to info.

Note that -v is equivalent to -log debug and -vv is equivalent to log trace, so this examples is just for setting the log level generically:

Selenium v4.10

    FirefoxDriverService service =
        new GeckoDriverService.Builder().withLogLevel(FirefoxDriverLogLevel.DEBUG).build();

Note: Java also allows setting log level by System Property:
Property key: GeckoDriverService.GECKO_DRIVER_LOG_LEVEL_PROPERTY
Property value: String representation of FirefoxDriverLogLevel enum

Selenium v4.11

    service = webdriver.FirefoxService(log_output=log_path, service_args=['--log', 'debug'])

Selenium v4.10

      service.args += %w[--log debug]

Truncated Logs

The driver logs everything that gets sent to it, including string representations of large binaries, so Firefox truncates lines by default. To turn off truncation:

Selenium v4.10

    FirefoxDriverService service =
        new GeckoDriverService.Builder().withTruncatedLogs(false).build();

Note: Java also allows setting log level by System Property:
Property key: GeckoDriverService.GECKO_DRIVER_LOG_NO_TRUNCATE
Property value: "true" or "false"

Selenium v4.11

    service = webdriver.FirefoxService(service_args=['--log-no-truncate', '--log', 'debug'], log_output=log_path)

Selenium v4.10

      service.args << '--log-no-truncate'

Profile Root

The default directory for profiles is the system temporary directory. If you do not have access to that directory, or want profiles to be created some place specific, you can change the profile root directory:

Selenium v4.10

    FirefoxDriverService service =
        new GeckoDriverService.Builder().withProfileRoot(profileDirectory).build();

Note: Java also allows setting log level by System Property:
Property key: GeckoDriverService.GECKO_DRIVER_PROFILE_ROOT
Property value: String representing path to profile root directory

    service = webdriver.FirefoxService(service_args=['--profile-root', temp_dir])

Selenium v4.8

      service.args += ['--profile-root', root_directory]

Special Features

Add-ons

Unlike Chrome, Firefox extensions are not added as part of capabilities as mentioned in this issue, they are created after starting the driver.

The following examples are for local webdrivers. For remote webdrivers, please refer to the Remote WebDriver page.

Installation

A signed xpi file you would get from Mozilla Addon page

    driver.installExtension(xpiPath);
    driver.install_addon(addon_path_xpi)
            driver.InstallAddOnFromFile(Path.GetFullPath(extensionFilePath));
      driver.install_addon(extension_file_path)
    let id = await driver.installAddon(xpiPath);

Uninstallation

Uninstalling an addon requires knowing its id. The id can be obtained from the return value when installing the add-on.

    driver.uninstallExtension(id);
    driver.uninstall_addon(id)

Selenium v4.5

            driver.UninstallAddOn(extensionId);
      driver.uninstall_addon(extension_id)
    await driver.uninstallAddon(id);

Unsigned installation

When working with an unfinished or unpublished extension, it will likely not be signed. As such, it can only be installed as “temporary.” This can be done by passing in either a zip file or a directory, here’s an example with a directory:

    driver.installExtension(path, true);
    driver.install_addon(addon_path_dir, temporary=True)

Selenium v4.5

            driver.InstallAddOnFromDirectory(Path.GetFullPath(extensionDirPath), true);

Selenium v4.5

      driver.install_addon(extension_dir_path, true)
    let id = await driver.installAddon(xpiPath, true);

Full page screenshots

The following examples are for local webdrivers. For remote webdrivers, please refer to the Remote WebDriver page.

    File screenshot = driver.getFullPageScreenshotAs(OutputType.FILE);
    driver.save_full_page_screenshot("full_page_screenshot.png")
        screenshot = driver.save_full_page_screenshot(File.join(dir, 'screenshot.png'))

Context

The following examples are for local webdrivers. For remote webdrivers, please refer to the Remote WebDriver page.

    ((HasContext) driver).setContext(FirefoxCommandContext.CHROME);
    driver.executeScript("console.log('Inside Chrome context');");
    with driver.context(driver.CONTEXT_CHROME):
        driver.execute_script("console.log('Inside Chrome context');")
      driver.context = 'content'