Download latest version of Selenium (4.8.3 at time of writing) Grab Andrew's magic browser config tool and add it to your Moodle config.php as in the setup: require_once('/path/to/moodle-browser-config/init.php'); Initialise behat php admin/tool/behat/cli/init.php or simply use mdk behat Inspect the generated behat.yml Confirm that there is only a goog:chromeOptions dictionary and no chromeOptions without prefix Init the downloaded selenium: /usr/bin/java -jar /path/to/selenium-server-4.8.3.jar standalone Run a behat run on a javascript behat feature using the headlesschrome profile: $ vendor/bin/behat --config /path/to/site/moodledata_behat/behatrun/behat/behat.yml --profile=headlesschrome --name="Use select and deselect all buttons" Confirm the test was executed headless without opening the browser