You can use Selenium directly if you need to use things that are not available through our commands. We use the NodeJS flavor of Selenium.

You get a hold of the Selenium objects through the context object.

The selenium.webdriver is the Selenium WebDriver public API object. And selenium.driver is the instantiated version of the WebDriver driving the current version of the browser.

Checkout this example to see how you can use them.

/**
 * @param {import('browsertime').BrowsertimeContext} context
 * @param {import('browsertime').BrowsertimeCommands} commands
 */
export default async function (context, commands) {
  // We fetch the selenium webdriver from context
  // The selenium-webdriver 
  // https://www.selenium.dev/selenium/docs/api/javascript/module/selenium-webdriver/index.html
  const seleniumWebdriver = context.selenium.webdriver;
  // The driver exposes for example By that you use to find elements
  const By = seleniumWebdriver.By;

  // We use the driver to find an element
  const seleniumDriver = context.selenium.driver;

  // To navigate to a new page it is best to use our navigation commands
  // so the script waits until the page is loaded
  await commands.navigate('https://www.sitespeed.io');

  // Lets use Selenium to find the Documentation link
  const seleniumElement = await seleniumDriver.findElement(By.linkText('Documentation'));
  
  // So now we actually got a Selenium WebElement 
  // https://www.selenium.dev/selenium/docs/api/javascript/module/selenium-webdriver/index_exports_WebElement.html
  context.log.info('The element tag is ', await seleniumElement.getTagName());

  // We then use our command to start a measurement
  await commands.measure.start('DocumentationPage');

  // Use the Selenium WebElement and click on it
  await seleniumElement.click();
  // We make sure to wait for the new page to load
  await commands.wait.byPageToComplete();

  // Stop the measuerment
  return commands.measure.stop();
}

If you need help with Selenium, checkout the official Selenium documentation.