Some clean-ups, clarification, and wording

source

@@ -80128,32 +80128,35 @@ dictionary <dfn dictionary>ToggleEventInit</dfn> : <span>EventInit</span> {
    <li><p>Let <var>container</var> be the <span>reading flow container</span> associated with
    <var>owner</var>.</p></li>
 
-   <li><p>Let <var>items</var> be the <span>rendering-defined sibling reading flow</span> of
-   <var>container</var>.</p></li>
+   <li><p>Let <var>items</var> be <var>container</var>'s <span>rendering-defined sibling reading
+   flow</span>.</p></li>
+
+   <li><p><span>Assert</span>: <var>items</var> is a <span>list</span> of <span
+   data-x="reading flow item">reading flow items</span>.</p></li>
 
    <li>
     <p><span data-x="list iterate">For each</span> <var>item</var> of <var>items</var>:</p>
 
     <ol>
-     <li><p><span>Assert</span>: <var>item</var> is a <span>reading flow item</span>.</p></li>
-
      <li>
       <p><span>While</span> <var>item</var> is not <var>container</var>:</p>
+
       <ol>
        <li>
-        <p>If <var>item</var>'s <span>associated focus navigation owner</span> is <var>owner</var>:</p>
+        <p>If <var>scope</var> <span data-x="list contains">contains</span> <var>item</var>:</p>
 
         <ol>
-         <li><p>If <var>output</var> does not <span data-x="list contains">contain</span>
-         <var>item</var>, <span data-x="list append">append</span> <var>item</var> to
-         <var>output</var>.</p></li>
+         <li>
+          <p>If <var>output</var> does not <span data-x="list contains">contain</span>
+          <var>item</var>, then <span data-x="list append">append</span> <var>item</var> to
+          <var>output</var>.</p>
+
+          <p class="note">Different <var>item</var>s can share the same <span>ancestor</span> in
+          <var>scope</var>; only add it to <var>output</var> the first time it is encountered.</p>
+         </li>
 
          <li><p><span>Break</span>.</p></li>
         </ol>
-
-        <p class="note">Different <var>item</var>s can have the same <span>inclusive
-        ancestor</span>. Only add to <var>output</var> if it is not already in the <span>reading
-        flow order</span>.</p>
        </li>
 
        <li><p>Set <var>item</var> to the parent element of <var>item</var> within the <span>flat
@@ -80162,22 +80165,34 @@ dictionary <dfn dictionary>ToggleEventInit</dfn> : <span>EventInit</span> {
      </li>
     </ol>
 
-    <p class="note">The <span>rendering-defined sibling reading flow</span> of <var>container</var>
-    includes <span data-x="descendant">descendants</span> of this <span>reading flow container</span>
-    that might not be in <var>scope</var>. For example, if a direct child of <var>container</var> has
-    CSS 'display: contents' and its nested children are included in <var>items</var>. Some elements in
-    <var>items</var> will have the <var>container</var> while others will have 'display: contents' child
-    as its <span>associated focus navigation owner</span>. This step traverses the <span
-    data-x="ancestor">ancestors</span> of <var>item</var> within the <span>flat tree</span> to make sure
-    we only include an element in the <span>reading flow order</span> if it is in <var>scope</var>.</p>
+    <div class="note">
+     <p><var>items</var> can include <span data-x="descendant">descendants</span> of
+     <var>container</var> that are not in <var>scope</var>. For example, when a direct child of
+     <var>container</var> has <code data-x="">display: contents</code>:</p>
+
+     <ul>
+      <li><p>The <code data-x="">display: contents</code> child will be in <var>scope</var>, but not
+      in <var>items</var>.</p></li>
+
+      <li><p>The <code data-x="">display: contents</code>'s own <span
+      data-x="concept-tree-child">children</span> will not be in <var>scope</var> (their
+      <span>associated focus navigation owner</span> is their parent), but can be in
+      <var>items</var>.</p></li>
+     </ul>
+
+     <p>This step includes in <var>output</var> the first <span>inclusive ancestor</span> of each
+     <var>item</var> that is also in <var>scope</var>. The result is that <var>output</var> is just
+     <var>scope</var>, but in reading flow order, as established by <var>items</var>.</p>
+    </div>
    </li>
 
    <li>
     <p><span data-x="list iterate">For each</span> <var>child</var> of <var>owner</var> element's <span
     data-x="concept-tree-child">children</span>, in <span>tree order</span>:</p>
+
     <ol>
-     <li><p>If <var>child</var>'s <span>associated focus navigation owner</span> is <var>owner</var>
-     and <var>output</var> does not <span data-x="list contains">contain</span> <var>child</var>,
+     <li><p>If <var>scope</var> <span data-x="list contains">contains</span> <var>child</var> and
+     <var>output</var> does not <span data-x="list contains">contain</span> <var>child</var>, then
      <span data-x="list append">append</span> <var>child</var> to <var>output</var>.</p></li>
     </ol>
    </li>