diff --git a/pytest.ini b/pytest.ini
index d7fe53494..94122db30 100644
--- a/pytest.ini
+++ b/pytest.ini
@@ -9,5 +9,10 @@
 # deprecation warnings and gives time for plugins that don't use the deprecated
 # API to propagate, especially for plugins packaged as an external snap, before
 # we release breaking changes.
+#
+# The current warnings being ignored are:
+# 1) The warning raised when importing certbot.tests.util and the external mock
+#    library is installed.
 filterwarnings =
     error
+    ignore:The external mock module:PendingDeprecationWarning