diff --git a/tests/settings/base.py b/tests/settings/base.py
index 7d67a0d..7a9682f 100644
--- a/tests/settings/base.py
+++ b/tests/settings/base.py
@@ -71,3 +71,4 @@
 STATIC_URL = "/static/"
 SITE_ID = 1
 WAGTAIL_SITE_NAME = "My Example Site"
+WAGTAILMARKDOWN_EXTENSIONS = ["toc"]
diff --git a/tests/test_pages.py b/tests/test_pages.py
index 6febe75..594b4de 100644
--- a/tests/test_pages.py
+++ b/tests/test_pages.py
@@ -59,3 +59,19 @@ def test_canonical_url(client):
         soup = BeautifulSoup(res.content, "html.parser")
         el = soup.find("link", attrs={"rel": "canonical"})
         assert el["href"] == "https://foo.com"
+
+
+def test_renders_toc(client):
+    post = BlogPage(
+        title="My post",
+        body="""
+[TOC]
+# first paragraph""",
+        date=timezone.now(),
+    )
+    pages = [(BlogIndexPage(title="index"), [post])]
+    with page_tree(pages):
+        [(_, [post])] = pages
+        res = client.get(post.get_url())
+    assert res.status_code == 200
+    assert BeautifulSoup(res.content, "html.parser").select(".toc")
diff --git a/tox.ini b/tox.ini
index 09b8d46..c28cc4b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -80,6 +80,8 @@ passenv =
 addopts = --ds=tests.settings.test --reuse-db -ra
 testpaths = tests
 norecursedirs = .git */migrations/* .venv
+filterwarnings =
+    ignore::django.utils.deprecation.RemovedInDjango40Warning
 
 [isort]
 recursive = True