Hey, thanks for replying. A couple things come to mind that make me question whether this should be closed or not.
If this is being closed because the capx link has expired, I can repost it. My fault; I didn't realize those links expired so soon. (You don't really need the capx; it can be done in any capx by adding a button with browser -> close, and running it in firefox.)
But more importantly, how do you make a browser game "quit" function without calling Browser -> Close? Or put another way, why is Browser -> Close an option in the Browser plug-in if it's inconsistent in different browsers? If the point of the feature is to close the window, but it doesn't always work, what's the valid use case for it?
I may have this wrong. But it seems strange to have a feature that depends on the browser; naturally people aren't developing just for Chrome with HTML5 games.