Additional clarifications to margin box generation and 'content'. <http://lists.w3.org/Archives/Public/www-style/2012Jun/0190.html>

Author: fantasai

css3-page/Overview.html

@@ -1270,9 +1270,13 @@ <h3 id=margin-at-rules><span class=secno>6.1. </span>At-rules for margin
    <h3 id=populating-margin-boxes><span class=secno>6.2. </span>Populating
     margin boxes</h3>
 
-   <p>A margin box is generated if and only if the computed value of its
-    ‘<code class=property>content</code>’ property does not match that of
-    its initial value. Otherwise it behaves as if it had ‘<code
+   <p>As with the ‘<code class=css>:before</code>’ and ‘<code
+    class=css>:after</code>’ pseudo-elements, a specified ‘<code
+    class=property>content</code>’ of ‘<code class=css>normal</code>’
+    on a margin box computes to ‘<code class=css>none</code>’, and the
+    margin box is generated if and only if the computed value of its ‘<code
+    class=property>content</code>’ property is not ‘<code
+    class=property>none</code>’. Otherwise it behaves as if it had ‘<code
     class=css>display: none</code>’.
 
    <div class=example>

css3-page/Overview.src.html

@@ -904,8 +904,10 @@ <h3 id="margin-at-rules">At-rules for margin boxes</h3>
 
 <h3 id="populating-margin-boxes">Populating margin boxes</h3>
 
-<p>A margin box is generated if and only if the computed value of its
-'content' property does not match that of its initial value.
+<p>As with the '':before'' and '':after'' pseudo-elements,
+a specified 'content' of ''normal'' on a margin box computes to ''none'',
+and the margin box is generated if and only if the computed value of its
+'content' property is not 'none'.
 Otherwise it behaves as if it had ''display: none''.
 
 <div class="example">