diff --git a/lib/web/fetch/util.js b/lib/web/fetch/util.js
index dc5ce9b392a..8583da1220f 100644
--- a/lib/web/fetch/util.js
+++ b/lib/web/fetch/util.js
@@ -472,7 +472,7 @@ function determineRequestsReferrer (request) {
 /**
  * @see https://w3c.github.io/webappsec-referrer-policy/#strip-url
  * @param {URL} url
- * @param {boolean|undefined} originOnly
+ * @param {boolean} [originOnly]
  */
 function stripURLForReferrer (url, originOnly) {
   // 1. Assert: url is a URL.