[whatwg] URL and Document

[Anne van Kesteren]

http://www.w3.org/html/wg/html5/#url says that URL is always associated  
with a Document. What does that mean for the second argument of  
postMessage? Or for the value of Websocket-Origin?

--
Anne van Kesteren
<http://annevankesteren.nl/>
<http://www.opera.com/>