diff --git a/source b/source
index 9e11deef691..1a3f40bea69 100644
--- a/source
+++ b/source
@@ -60181,7 +60181,10 @@ interface <dfn interface>HTMLDialogElement</dfn> : <span>HTMLElement</span> {
 
      <li><p>Set <var>subject</var>'s <span>previously focused element</span> to null.</p></li>
 
-     <li><p>Run the <span>focusing steps</span> for <var>element</var>; the viewport should not be
+     <li><p>If <var>subject</var>'s <span>node document</span>'s <span>focused area of the
+     document</span>'s <span>DOM anchor</span> is a <span>shadow-including inclusive
+     descendant</span> of <var>element</var>, or <var>subject</var>'s <span>is modal</span> is true,
+     then run the <span>focusing steps</span> for <var>element</var>; the viewport should not be
      scrolled by doing this step.</p></li>
     </ol>
    </li>