diff --git a/trusted-types/block-string-assignment-to-Element-setAttributeNS.html b/trusted-types/block-string-assignment-to-Element-setAttributeNS.html
index 2eb5506cc827d5..b7f74be6b7dd22 100644
--- a/trusted-types/block-string-assignment-to-Element-setAttributeNS.html
+++ b/trusted-types/block-string-assignment-to-Element-setAttributeNS.html
@@ -73,8 +73,7 @@
     ];
 
     for (const testData of nonLowerCaseTests) {
-      const attributeNamespace = ("attributeNamespace" in testData) ?
-          testData.attributeNamespace : null;
+      const attributeNamespace = testData.attributeNamespace ?? null;
 
       test(t => {
         assert_element_accepts_non_trusted_type_set_ns(testData.element, testData.attribute, "v",