diff --git a/tox.ini b/tox.ini
index b602c4f0..240b8364 100644
--- a/tox.ini
+++ b/tox.ini
@@ -10,8 +10,8 @@ setenv =
   VIRTUAL_ENV={envdir}
   LANGUAGE=en_US
   LC_ALL=en_US.utf-8
-passenv=
-  GITHUB_REF_NAME,
+passenv =
+  GITHUB_REF_NAME
   GITHUB_BASE_REF
 commands =
   python -m unittest -v