I've never heard of Pentadactyl to this day.
So my guess you are a small user base, and Mozilla can safely accept to loose you.
You can't satisfy everybody.
What everybody want's right now is a faster browser. That's the main requested feature. That what's everyone agree on.
The new extension model is an important step to do that. There is no way around it. XUL extensions drag the browser down.
So if in order to satisfy most user FF has to let you down, it makes sense. It's sad. I understand your frustration. But it's the logical choice.
Talk for yourself, not on everyone's behalf
> I've been using Firefox for so long it was called phoenix at the time. I used a LOT of extensions, take part of the testing of unstable versions and test pilots and everything. I've never heard of Pentadactyl to this day.
Not a surprise. It's not like you have to memorize list of all extensions before using "unstable versions and test pilots and everything."
> So my guess you are a small user base, and Mozilla can safely accept to loose you.
Thanks for reminding us your use case is the only one that matters end everybody else is expendable.
You might have heard of Vimperator though, which Pentadactyl is a fork of. According to AMO, Vimperator has a lot more users and I guess the same implementation issues apply to it with regard to WebExtensions.
I switched over from Pentadactyl to Qutebrowser last year and it's way snappier. And with the experimental WebEngine backend, I haven't run into any rendering or performance issues at all. It also has a vertical tab mode, although it isn't possible to have sub-tabs like Tree Style Tabs.