It's still not clear to me whether you actually tried to work with the Mozilla devs or if this is still fueled from your initial (in my opinion rather rushed) statement and some form of false pride.

But yeah, I'd just like to say that in case you did not do your best to maybe get to a solution with the Mozilla devs, that I'd appreciate it, if you could try again.

I don't personally use your add-on, but I know that a lot of people do and I think that this initial discourse to get some of the APIs sorted out is rather important.

Even if you don't end up writing the extension, it'd be good to have reasonable APIs at least drafted. So that maybe someone can offer a half-assed Down Them All, which maybe is already good enough for some people, and then maybe that add-on's developer can continue working with Mozilla to get a proper API fully sorted.

You should also consider that Mozilla started out with this "webby" state from Chrome. Anything modifying the UI and so on still needs to be defined. Once they have some of the other UI-APIs worked out, it'll be easier for Mozilla to fit new libraries into there and then it'll also be easier for Mozilla to work with your API needs.