def test_create_a_firefox_instance_with_extension(self):
        self.assertIn(
            'firebug@software.joehewitt.com',
            os.listdir(self.browser.driver.profile.extensionsDir)
        )
should be able to load an extension
dataset/ETHPy150Open cobrateam/splinter/tests/test_webdriver_firefox.py/FirefoxWithExtensionTest.test_create_a_firefox_instance_with_extension