> Well, I'm a Firefox user, not an extension developer, and Pentadactyl happened to be one of the extensions that made using Firefox bearable. Now that it's permanently broken,

Pentadactyl was all-but-abandoned for years before Vimperator was broken. It's been almost four years since it saw a release - which was for Firefox 24.0-30[0]. Its website still links at least three links to code.google.com on the front page! (I'm actually shocked if Pentadactyl has even been working for you until now, given that it was supposed to break a few release cycles ago - when e10s shipped - but maybe you just haven't updated Firefox in a while, or you manually disabled e10s.)

Vimperator - which is also incompatible with Firefox 55+ for the same reasons Pentadactyl is - at least has been receiving maintenance attention in the meantime[1], and also provides alternatives for use with Firefox 55+ (and 57+).

If you'd rather switch browsers entirely than use something like Vimium[2] on Firefox, go ahead, but it's hard to justify holding an entire browser back just to maintain compatibility with an extension that has been abandoned by its own maintainers. As I mentioned, I can't even reasonably expect them to hold Firefox back to maintain compatibility with the extensions I wrote and actively maintained. As a Firefox developer, I'm disappointed, but as a Firefox user, I'm more than happy enough with the changes to make up for it.

[0] http://5digits.org/pentadactyl/

[1] https://github.com/vimperator/vimperator-labs

[2] https://addons.mozilla.org/en-US/firefox/addon/vimium-ff/?sr...

Despite there being no official releases in years and being abandoned by its official developers, Pentadactyl was kept afloat by its users, from whom you could still get fixes and releases through google code and google groups. I also fixed some things for myself, based on help from the community. Despite all this, it did finally completely break recently (before FF 57), and I just had to not update FF for a while until I found an alternative. I used PaleMoon for a while, but now I'm switching to Qutebrowser.

"it's hard to justify holding an entire browser back just to maintain compatibility with an extension that has been abandoned by its own maintainers"

Pentadactyl was far from the only extension that Firefox decided to break. Many other extensions were affected.

As far as Pentadactyl itself went, the reason its maintainers abandoned it was because Firefox kept breaking compatibility with it over, and over, and over, and over. They understandably got frustrated by that and moved on to other things.

Then, when Firefox put their foot down and announced that they'd be changing the browser so that Pentadactyl will never again be able to work on it, no matter what its developers did, a lot of people didn't see the point of putting more effort in to. It survived only because of the dedication and help of the remaining community. Now there's nothing even they can do. Not with Firefox anyway. So we're moving on to something else.

you are a tiny minority and a specialized browser fork is a great solution for your use case in this situation.

I think that's a great point: it's difficult, near impossible, to make any particular piece of software contain 100% of the features that 100% of people want. Especially in the case of a tiny-minority feature, a specialized version that caters to your needs sometimes makes the most sense.

I just worry that people using some of these alternative browsers are opening themselves up to security issues since those code bases are less well-tested for security problems, and often they don't have the developer resources to implement things like process isolation and sandboxing.

> I just worry that people using some of these alternative browsers are opening themselves up to security issues since those code bases are less well-tested for security problems

Absolutely. The web browser is one of the most notorious attack vectors on computers these days. I find it hilarious that a vocal minority of power users is protesting this _massively impressive_ Firefox release just because they lost Tree Style Tabs or some extensions for downloading videos. Switching to a legacy fork like Waterfox or Firefox 52 ESR is not an enlightened move!

We lost NoScript!

Pentadactyl was the greatest browser extension ever created. I hope that something similar will appear in the future.

Well, I'm a Firefox user, not an extension developer, and I much prefer a performant browser with modern security features (and the ability to implement more in the future, which they couldn't do pre-57). I've lost a couple extensions during the move, but the tradeoff is well worth it to me.

And it sucks that you don't feel that way -- it really does -- but I suspect the vast majority of Firefox users feel as I do, and in the end Mozilla needs to cater to the most users possible.