Add test about updatable-rec

Author: marcoscaceres

index.html

@@ -77,6 +77,11 @@ <h3>
           more available across all OSs over time, and is already widely
           available on popular OSs across a range of devices.
         </p>
+        <p>
+          <!-- TODO: Remove me when this goes to REC, otherwise it will show up twice! -->
+           Future updates to this Recommendation may incorporate [new
+          features](https://www.w3.org/2021/Process-20211102/#allow-new-features).
+        </p>
       </section>
     </section>
     <section class="informative">