nsIDOMWindowInternal Interface

 Open a new window with this one as the parent.  This method will
 NOT examine the JS stack for purposes of determining a caller.
 This window will be used for security checks during the search by
 name and the default character set on the newly opened window
 will just be the default character set of this window.

[noscript] nsIDOMWindow open(in DOMString url, in DOMString name, in DOMString options)

 This method works like open except that aExtraArgument gets
 converted into the array window.arguments in JS, if
 aExtraArgument is a nsISupportsArray then the individual items in
 the array are inserted into window.arguments, and primitive
 nsISupports (nsISupportsPrimitives) types are converted to native
 JS types when possible.

[noscript] nsIDOMWindow openDialog(in DOMString url, in DOMString name, in DOMString options, in nsISupports aExtraArgument)

 Implements a safe message-passing system which can cross same-origin
 boundaries.

 This method, when called, causes a MessageEvent to be asynchronously
 dispatched at the primary document for the window upon which this method is
 called.  (Note that the postMessage property on windows is allAccess and
 thus is readable cross-origin.)  The dispatched event will have message as
 its data, the calling context's window as its source, and an origin
 determined by the calling context's main document URI.  The targetOrigin
 argument specifies a URI and is used to restrict the message to be sent
 only when the target window has the same origin as targetOrigin (since,
 when the sender and the target have different origins, neither can read the
 location of the other).
 
 See the WHATWG HTML5 specification, section 6.4, for more details.

[binaryname(PostMessageMoz)] void postMessage(in DOMString message, in DOMString targetOrigin)