diff --git a/docs/index.bs b/docs/index.bs
index 8b80ce9d..381c53d9 100644
--- a/docs/index.bs
+++ b/docs/index.bs
@@ -1804,6 +1804,7 @@ spec: webappsec-referrer-policy; urlPrefix: https://w3c.github.io/webappsec-refe
       1. Let |scopeURL| be null.
       1. If the <{link/scope}> attribute is present, set |scopeURL| to the result of <a lt="URL parser">parsing</a> the <{link/scope}> attribute with the <{link}> element's <a>node document</a>'s <a>document base URL</a>.
       1. Let |workerType| be the state of the <{link/workertype}> attribute.
+      1. If |workerType| is "<code>invalid</code>", <a>queue a task</a> to <a>fire an event</a> named <code>error</code> at the <{link}> element, and abort these steps.
       1. Let |useCache| be true if the <{link}> element has a <{link/usecache}> attribute, otherwise false.
       1. Let |promise| be a new <a>promise</a>.
       1. Invoke [=Start Register=] with |scopeURL|, |scriptURL|, |promise|, |client|, |client|'s <a>creation URL</a>, |workerType|, and |useCache|.