diff --git a/tox.ini b/tox.ini
index b06e60f..b9a1da3 100644
--- a/tox.ini
+++ b/tox.ini
@@ -33,9 +33,14 @@ commands =
 
 [testenv:py35dj20]
 basepython = python3.5
+whitelist_externals = git
 commands =
-    pip install django>=2.0,<2.1
-    python manage.py test {posargs}
+  # NOTE(shu-mutow): To test this new env, need to re-install recent horizon
+  # from git master branch like CI infra does.
+  git clone https://git.openstack.org/openstack/horizon.git .tox/py35dj20/src/horizon
+  pip install -U -t .tox/py35dj20/lib/python3.5/site-packages/ .tox/py35dj20/src/horizon
+  pip install django>=2.0,<2.1
+  python manage.py test {posargs}
 
 [testenv:eslint]
 whitelist_externals = npm