Updated link to Selenium webdrivers.
@@ -260,7 +260,7 @@ the tests that require selenium.
Some browsers (e.g. Chrome or Firefox) support headless testing, which can be
faster and more stable. Add the ``--headless`` option to enable this mode.
-.. _selenium.webdriver: https://github.com/SeleniumHQ/selenium/tree/master/py/selenium/webdriver
+.. _selenium.webdriver: https://github.com/SeleniumHQ/selenium/tree/trunk/py/selenium/webdriver
.. _running-unit-tests-dependencies:
