1 files changed, 2 insertions, 1 deletions
diff --git a/testing/web-platform/tests/navigation-api/navigate-event/navigate-location.html b/testing/web-platform/tests/navigation-api/navigate-event/navigate-location.html
index a0ed4dc0aa..b1ce204a62 100644
--- a/testing/web-platform/tests/navigation-api/navigate-event/navigate-location.html
+++ b/testing/web-platform/tests/navigation-api/navigate-event/navigate-location.html
@@ -17,7 +17,8 @@ async_test(t => {
     assert_equals(e.destination.id, "");
     assert_equals(e.destination.index, -1);
     assert_equals(e.formData, null);
-    assert_equals(e.sourceElement, null);
+    // NavigateEvent sourceElement is still in development, so test whether it is available.
+    if ("sourceElement" in e) assert_equals(e.sourceElement, null);
   });
   location.href = "#1";
 }, "location API fires navigate event");