How about to just execute:
Thanks for the suggestion, but it does not work.
Works for me in IE.
It does not work in Safari or Firefox on the Mac. I don't know why this should be.
js: window.close() is not allowed to close the main window ( unless it is opened by another window ) in some broswers.
i faced similar need, what i did is just display the blank screen:
navigateToURL( new urlRequest("about:blank"));
i know it is not final solution, but this is what i could do.