From Frozen to unfrozen state. hmm

I noticed that the “nsIDOMHTMLImageElement” interface all the sudden
went from Frozen to unfrozen state in Firefox 4.0 which surprised me a
bit.

It would be great if you guys could document / list all the interfaces
that moved from Frozen to Unfrozen state. I must admit that you guys
make it a bit difficult for us extension developers if we can’t rely
on a frozen interface to actually  to stay frozen.

If you need to extent “nsIDOMHTMLImageElement” after it has been
declared frozen why not implement “nsIDOMHTMLImageElement2” and
inherit from “nsIDOMHTMLImageElement”?