adopt all of Maciej's suggestions

Author: annevk

source

@@ -88522,12 +88522,11 @@ import "https://example.com/foo/../module2.js";</pre>
    </dd>
   </dl>
 
-  <p>To determine the manifestation of JavaScript's <span>agent cluster</span> concept in user
-  agents, we define which <span data-x="agent">agents</span> <dfn>can share memory with</dfn>
-  another. Then all the <span data-x="agent">agents</span> that can <span>can share memory
-  with</span> each other form an <span>agent cluster</span>.</p>
+  <h5>Integration with the JavaScript agent cluster formalism</h5>
 
-  <p class="note">The <span>can share memory with</span> relation is symmetric.</p>
+  <p><dfn>Can share memory with</dfn> defines an equivalence relation. An <span>agent cluster</span>
+  consists of all <span data-x="agent">agents</span> in the same equivalence class with respect to
+  the <span>can share memory with</span> equivalence relation.</p>
 
   <p>A <span>similar-origin window agent</span>, <span>dedicated worker agent</span>, <span>shared
   worker agent</span>, or <span>service worker agent</span>, <var>agent</var>, <span>can share
@@ -88544,6 +88543,19 @@ import "https://example.com/foo/../module2.js";</pre>
   href="https://github.com/w3c/css-houdini-drafts/issues/224">w3c/css-houdini-drafts issue
   #224</a>.</p>
 
+  <p>In addition, any <span>agent</span> <var>A</var> <span>can share memory with</span>:</p>
+
+  <ul class="brief">
+   <li><var>A</var>,</li>
+
+   <li>any <span>agent</span> <var>B</var> such that <var>B</var> <span>can share memory with</span>
+   <var>A</var>, and</li>
+
+   <li>any <span>agent</span> <var>B</var> such that there exists an <span>agent</span>
+   <var>C</var>, where <var>A</var> <span>can share memory with</span> <var>C</var> and <var>C</var>
+   <span>can share memory with</span> <var>B</var>.</li>
+  </ul>
+
   <p>The <span>agent cluster</span> concept is crucial for defining the JavaScript memory model, and
   in particular among which <span data-x="agent">agents</span> the backing data of
   <code>SharedArrayBuffer</code> objects can be shared.</p>