Take n, back to transitive closure

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@@ -88546,30 +88546,56 @@ import "https://example.com/foo/../module2.js";</pre>
    </dd>
   </dl>
 
+  <p>For convenience in what follows, for all <span data-x="agent">agents</span> that are not <span
+  data-x="similar-origin window agent">similar-origin window agents</span>, we define <dfn
+  data-x="concept-agent-global">the agent's global object</dfn> to be the <span
+  data-x="concept-realm-global">global object</span> of the single <span data-x="JavaScript
+  realm">realm</span> in the agent's set of realms.</p>
+
   <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>
+  agents, we define which <span data-x="agent">agents</span> <dfn>can directly share memory
+  with</dfn> another:</p>
 
-  <p class="note">The <span>can share memory with</span> relation is symmetric.</p>
+  <dl class="switch">
+   <dt><span>Similar-origin window agent</span></dt>
+   <dd><p>Any <span>dedicated worker agent</span> whose <span data-x="concept-agent-global">global
+   object</span>'s <span>owner set</span> contains a <code>Document</code> object whose <span
+   data-x="concept-relevant-realm">relevant Realm</span> belongs to <var>agent</var>.</p></dd>
 
-  <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
-  memory with</span> any <span>dedicated worker agent</span> whose single <span data-x="JavaScript
-  realm">realm</span>'s <span data-x="concept-realm-global">global object</span>'s <span>owner
-  set</span> contains an item whose <span data-x="concept-relevant-realm">relevant Realm</span>
-  belongs to <var>agent</var>.</p>
+   <dt><span>Dedicated worker agent</span></dt>
+   <dd>
+    <p>Any <span>agent</span> with a <span data-x="JavaScript realm">realm</span> that is the <span
+    data-x="concept-relevant-realm">relevant Realm</span> of an item in <var>agent</var>'s
+    <span data-x="concept-agent-global">global object</span>'s <span>owner set</span>.</p>
 
-  <p class="note">We use item above as an <span>owner set</span> can contain <code>Document</code>
-  objects.</p>
+    <p class="note">Recall that the <span>owner set</span> can contain both <code>Document</code>
+    and <code>WorkerGlobalScope</code> objects.</p>
+   </dd>
+
+   <dt><span>Worklet agent</span></dt>
+   <dd><p class="&#x0058;&#x0058;&#x0058;">Currently worklets have no clearly defined owner, see: <a
+   href="https://github.com/w3c/css-houdini-drafts/issues/224">w3c/css-houdini-drafts issue
+   #224</a>.</p></dd>
+
+   <dt><span>Shared worker agent</span></dt>
+   <dt><span>Service worker agent</span></dt>
+   <dd><p>Any <span>dedicated worker agent</span> whose <span data-x="concept-agent-global">global
+   object</span> is in <var>agent</var>'s <span data-x="concept-agent-global">global object</span>'s
+   <span>worker set</span>.</p></dd>
+  </dl>
+
+  <p>In addition, any <span>agent</span> <span>can directly share memory with</span> itself.</p>
 
-  <p class="&#x0058;&#x0058;&#x0058;">A <span>worklet agent</span> &hellip; currently worklets have
-  no clearly defined owner, see: <a
-  href="https://github.com/w3c/css-houdini-drafts/issues/224">w3c/css-houdini-drafts issue
-  #224</a>.</p>
+  <p>Given the above definition, <span>can directly share memory with</span> is a reflexive and
+  symmetric binary relation over the set of all <span data-x="agent">agents</span>. We then define
+  the <dfn>can share memory with</dfn> binary relation as the transitive closure of <span>can
+  directly share memory with</span>. Thus, <span>can share memory with</span> is an equivalence
+  relation: it is reflexive, symmetric, and transitive. We finally define the <span data-x="agent
+  cluster">agent clusters</span> to be the equivalence classes of <span>can share memory
+  with</span>.</p>
 
-  <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
+  <p class="note">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>
 
   <div class="example">