diff --git a/source b/source
index 2f6d690e48d..6cbc38d1038 100644
--- a/source
+++ b/source
@@ -79012,9 +79012,8 @@ END:VCARD</pre>
   data-x="navigate-fragid">fragment navigation</span>. When these features attempt to scroll to a
   target which is in the element's subtree, the user agent will remove the <code
   data-x="attr-hidden">hidden</code> attribute in order to reveal the content before scrolling to
-  it. In addition to removing the <code data-x="attr-hidden">hidden</code> attribute, an event named
-  <code data-x="event-beforematch">beforematch</code> is also fired on the element before the <code
-  data-x="attr-hidden">hidden</code> attribute is removed.</p>
+  it by running the <span>ancestor hidden-until-found revealing algorithm</span> on the target
+  node.</p>
 
   <p>Web browsers will use 'content-visibility: hidden' instead of 'display: none' when the <code
   data-x="attr-hidden">hidden</code> attribute is in the <span
@@ -79179,7 +79178,8 @@ END:VCARD</pre>
 
       <ol>
        <li><p><span data-x="concept-event-fire">Fire an event</span> named <code
-       data-x="event-beforematch">beforematch</code> at <var>currentNode</var>.</p></li>
+       data-x="event-beforematch">beforematch</code> at <var>currentNode</var> with the <code
+       data-x="dom-Event-bubbles">bubbles</code> attribute initialized to true.</p></li>
 
        <li><p>Remove the <code data-x="attr-hidden">hidden</code> attribute from
        <var>currentNode</var>.</p></li>