> Sorry, but that is just wrong, Certain types of APIs are infeasible to provide, because mozilla is too time and resource constrained to invest major resources into spec'ing, implementing and maintaining "niche" APIs.

I don't know how you come to this conclusion. They've been able to maintain XUL up until now and whatever they end up with in this new API, it'll be cheaper to maintain than the monstrosity that is XUL extensions.

The specification and implementation are done in cooperation with the add-on developers. They can draw from the community here.

And while they haven't reached Chrome parity yet, they do have already implemented some additional APIs. You're writing as if one thing would block the other.