I think a smarter approach would be introduce this new API and only deprecate the portions of XUL that haven't been replicated in the new API. Once you reach parity you do the rest as you suggest.
Depreciating functionality doesn't mean the functionality goes away immediately, it just means it's not recommended to use.
Mozilla isn't stopping people from using XUL by depreciating it, they're suggesting that developers should avoid it, as it'll eventually be taken away. The two extension systems will both be available until a sufficient portion of Firefox extensions have been migrated over to the new APIs.
Or to put it in another way, good news, they're doing what you said!
Mozilla isn't stopping people from using XUL by depreciating it, they're suggesting that developers should avoid it, as it'll eventually be taken away. The two extension systems will both be available until a sufficient portion of Firefox extensions have been migrated over to the new APIs.
Or to put it in another way, good news, they're doing what you said!