</pre>
TODOI emailed jst for his opinion: connect with jst <blockquote>Fortunately we're past the time when we were unable to change interfaces and figure out which way were forced to add more. In your case, I would simply goahead and change the nsIDOMNavigator interface, but do make sure you bump the IID before the changes land. Also, we recently made the navigator as seen from JS expandable w/o changing the interface by simply registering an XPCOM category, so if that's of any use for you guys that's an option too. I suspect in the case of mouse lock you'll want a binary implementation anyways, so writing this in C++ directly makes sense to me, but if not, there are other options.</blockquote>