diff --git a/pyproject.toml b/pyproject.toml
index 4443559..aa4c15a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -108,6 +108,7 @@ dev = [
     "mkdocs-material>=9.5",
     "mkdocs-minify-plugin>=0.8",
     "mkdocstrings[python]>=0.25",
+    "pymdown-extensions>=10.14",
     # YORE: EOL 3.10: Remove line.
     "tomli>=2.0; python_version < '3.11'",
 ]
\ No newline at end of file
diff --git a/tests/test_references.py b/tests/test_references.py
index 323813d..585529e 100644
--- a/tests/test_references.py
+++ b/tests/test_references.py
@@ -116,7 +116,7 @@ def test_reference_implicit_with_code_inlinehilite_python() -> None:
         extensions={"pymdownx.inlinehilite": {"style_plain_text": "python"}, "pymdownx.highlight": {}},
         url_map={"pathlib.Path": "pathlib.html#Path"},
         source="This [`pathlib.Path`][].",
-        output='<p>This <a class="autorefs autorefs-internal" href="pathlib.html#Path"><code class="highlight">pathlib.Path</code></a>.</p>',
+        output='<p>This <a class="autorefs autorefs-internal" href="pathlib.html#Path"><code class="language-python highlight">pathlib.Path</code></a>.</p>',
     )