Editorial: remove byte dfn

Author: marcoscaceres

index.html

@@ -931,7 +931,7 @@ <h2>
         };
       </pre>
       <p>
-        <a>PushMessageData</a> objects have an associated <dfn>bytes</dfn> (a byte sequence) set on
+        <a>PushMessageData</a> objects have an associated [=byte sequence=] set on
         creation, which is `null` if there was no data in the <a>push message</a>.
       </p>
       <p>