diff --git a/pyproject.toml b/pyproject.toml
index ead8162b..f7e22d4a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,3 +1,6 @@
 [build-system]
 requires = ["setuptools>=46.4.0", "wheel"]
 build-backend = "setuptools.build_meta"
+
+[tool.pytest.ini_options]
+xfail_strict = true
diff --git a/tests/test_port/test_fixtures.py b/tests/test_port/test_fixtures.py
index a789fb1f..5117c5e1 100644
--- a/tests/test_port/test_fixtures.py
+++ b/tests/test_port/test_fixtures.py
@@ -77,12 +77,6 @@ def test_commonmark_extras(line, title, input, expected):
     read_fixture_file(FIXTURE_PATH.joinpath("normalize.md")),
 )
 def test_normalize_url(line, title, input, expected):
-    if title in {
-        "Keep %25 as is because decoding it may break urls, #720",
-        "Square brackets are allowed",
-    }:
-        # TODO fix failing url escaping test
-        pytest.xfail("url normalisation")
     md = MarkdownIt("commonmark")
     text = md.render(input)
     assert text.rstrip() == expected.rstrip()