Remove connectedness check in script post-connection steps

Author: domfarolino

source

@@ -64313,14 +64313,17 @@ o............A....e
   <var>insertedNode</var>, are:</p>
 
   <ol>
-   <li>
-    <p>If <var>insertedNode</var> is not <span>connected</span>, then return.</p>
+   <li><p>If <var>insertedNode</var> is <span>parser-inserted</span>, then return.</p></li>
 
-    <div class="example">
-     <p>This can happen in the case where an earlier-inserted <code>script</code> removes a
-     later-inserted <code>script</code>. For instance:</p>
+   <li><p><span>Prepare the script element</span> given <var>insertedNode</var>.</p></li>
+  </ol>
 
-     <pre><code class="html">&lt;script>
+  <div class="example">
+   <p>The <span>HTML element post-connection steps</span> only run when the inserted element is
+   still <span>connected</span>, which protects against cases where an earlier-inserted
+   <code>script</code> removes a later-inserted <code>script</code>. For instance:</p>
+
+   <pre><code class="html">&lt;script>
 const script1 = document.createElement('script');
 script1.innerText = `
   document.querySelector('#script2').remove();
@@ -64333,20 +64336,14 @@ script2.textContent = `console.log('script#2 running')`;
 document.body.append(script1, script2);
 &lt;/script></code></pre>
 
-     <p>Nothing is printed to the console in this example. By the time the <span>HTML element
-     post-connection steps</span> run for the first <code>script</code> that was atomically inserted
-     by <code data-x="dom-Node-append">append()</code>, it can observe that the second
-     <code>script</code> is already <span>connected</span> to the DOM. It removes the second
-     <code>script</code>, so that by the time <em>its</em> <span>HTML element post-connection
-     steps</span> run, it is no longer <span>connected</span>, and does not get <span
-     data-x="prepare the script element">prepared</span>.</p>
-    </div>
-   </li>
-
-   <li><p>If <var>insertedNode</var> is <span>parser-inserted</span>, then return.</p></li>
-
-   <li><p><span>Prepare the script element</span> given <var>insertedNode</var>.</p></li>
-  </ol>
+   <p>Nothing is printed to the console in this example. By the time the <span>HTML element
+   post-connection steps</span> run for the first <code>script</code> that was atomically inserted
+   by <code data-x="dom-Node-append">append()</code>, it can observe that the second
+   <code>script</code> is already <span>connected</span> to the DOM, and it removes it from the DOM.
+   Because the second <code>script</code> is no longer <span>connected</span>, its <span>HTML
+   element post-connection steps</span> do not run, and it does not get <span data-x="prepare the
+   script element">prepared</span>.</p>
+  </div>
 
   <p>The <code>script</code> <span>HTML element removing steps</span> given <var>removedNode</var>
   are:</p>
@@ -64373,6 +64370,8 @@ document.body.append(script1, script2);
   are:</p>
 
   <ol>
+   <li><p>If the <code>script</code> element is not <span>connected</span>, then return.</p></li>
+
    <li><p>Run the <code>script</code> <span>HTML element post-connection steps</span>, given
    <var>changedNode</var>.</p></li>
   </ol>
@@ -64426,9 +64425,9 @@ document.body.append(script1, script2);
   <ol>
    <li><p>If <var>namespace</var> is not null, then return.</p></li>
 
-   <li><p>If <var>localName</var> is <code data-x="attr-script-src">src</code>, then run the
-   <code>script</code> <span>HTML element post-connection steps</span>, given
-   <var>element</var>.</p></li>
+   <li><p>If <var>localName</var> is <code data-x="attr-script-src">src</code> and
+   <var>element</var> is <span>connected</span>, then run the <code>script</code> <span>HTML element
+   post-connection steps</span>, given <var>element</var>.</p></li>
   </ol>
 
   <p id="prepare-a-script">To <dfn>prepare the script element</dfn> given a <code>script</code>