Hi,
Noted that the HTML5 spec (W3C editors draft) relies on 'onmessage' and
the MessageEvent, which afaict isn't part of the spec and is only
defined in the whatwg version (under section 9.1).
There is a small note in the w3c version (sec 6.1.6.1):
"Certain event handler IDL attributes have additional requirements,
in particular the onmessage attribute of MessagePort objects."
But no pointers, perhaps it belongs in the w3c version as well if it's a
dependency, or a pointer at least so implementers can find it (maybe
there is a link that I missed).
Best,
Nathan