diff --git a/docs/internals/contributing/writing-code/unit-tests.txt b/docs/internals/contributing/writing-code/unit-tests.txt
index fe1d1060b8..e421147b40 100644
--- a/docs/internals/contributing/writing-code/unit-tests.txt
+++ b/docs/internals/contributing/writing-code/unit-tests.txt
@@ -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: