mark section as informative

Author: scottaohara

index.html

@@ -5135,7 +5135,7 @@ <h2>
         A conformance checker MAY define their own terminology, and level or levels of severity, when surfacing document failures to conform to this specification.
       </p>
     </section>
-    <section id="priv-sec">
+    <section id="priv-sec" class="informative">
       <h2>
         Privacy and security considerations
       </h2>