Yea I saw the use of level in the example but didn't think to look at the text/html spec to see if it was there. That would seem to imply that you are correct (

Yea I saw the use of level in the example but didn't think to look at the text/html spec to see if it was there. That would seem to imply that you are correct (though it would be nice if there were an explicit answer on this, if only for purely OCD reasons). > just as media types are not necessarily IANA-registered incidentally Per RFC4288 I believe they must be if they are in the standard tree (i.e. the name does not contain a '.' or an 'x-' prefix for historical reasons).