diff --git a/source b/source
index 24deb7efbb8..d960294375f 100644
--- a/source
+++ b/source
@@ -4540,6 +4540,7 @@ a.setAttribute('href', 'https://example.com/'); // change the content attribute
     <ref>SECURE-CONTEXTS</ref></p>
 
     <ul class="brief">
+     <li><dfn data-x-href="https://w3c.github.io/webappsec-secure-contexts/#potentially-trustworthy-origin">Is origin potentially trustworthy?</dfn></li>
      <li><dfn data-x-href="https://w3c.github.io/webappsec-secure-contexts/#potentially-trustworthy-url">Is url potentially trustworthy?</dfn></li>
     </ul>
    </dd>
@@ -106878,19 +106879,9 @@ interface <dfn interface>NotRestoredReasons</dfn> {
     </ul>
    </li>
 
-   <li>
-    <p>Let <var>topLevelCreationURL</var> be the return value of running these steps:</p>
-
-    <ol>
-     <li><p>If <var>embedder</var> is non-null, then return <var>embedder</var>'s <span>relevant
-     settings object</span>'s <span>top-level creation URL</span>.</p></li>
-
-     <li><p>If <var>creator</var> is non-null, then return <var>creator</var>'s <span>relevant
-     settings object</span>'s <span>top-level creation URL</span>.</p></li>
-
-     <li><p>Return <code>about:blank</code>.</p></li>
-    </ol>
-   </li>
+   <li><p>Let <var>topLevelCreationURL</var> be <code>about:blank</code> if <var>embedder</var> is
+   null; otherwise <var>embedder</var>'s <span>relevant settings object</span>'s <span>top-level
+   creation URL</span>.</p></li>
 
    <li><p>Let <var>topLevelOrigin</var> be <var>origin</var> if <var>embedder</var> is null;
    otherwise <var>embedder</var>'s <span>relevant settings object</span>'s <span>top-level
@@ -118676,6 +118667,20 @@ document.querySelector("button").addEventListener("click", bound);
    data-x="concept-url-scheme">scheme</span> is "<code data-x="">data</code>", then return
    false.</p></li>
 
+   <li>
+    <p>If <var>environment</var>'s <span>top-level creation URL</span> <span>matches
+    <code>about:blank</code></span> and <var>environment</var>'s <span>top-level origin</span> is
+    non-null, then return true if the result of <span>Is origin potentially trustworthy?</span>
+    given <var>environment</var>'s <span>top-level origin</span> is "<code data-x="">Potentially
+    Trustworthy</code>"; otherwise false.</p>
+
+    <p class="note">A top-level <code>Document</code> whose <span
+    data-x="concept-document-url">URL</span> <span>matches <code>about:blank</code></span>, such as
+    a popup's initial <code>about:blank</code> <code>Document</code> or one created by navigating to
+    <code>about:blank</code>, inherits its <span data-x="concept-document-origin">origin</span> but
+    has <code>about:blank</code> as its <span>top-level creation URL</span>.</p>
+   </li>
+
    <li><p>If the result of <span>Is url potentially trustworthy?</span> given
    <var>environment</var>'s <span>top-level creation URL</span> is "<code data-x="">Potentially
    Trustworthy</code>", then return true.</p></li>