I was skeptical of the move to Firefox Quantum originally because of the extension-breaking, but after it happened, I can see the motivation: after upgrading, Firefox got a lot faster and less prone to memory leaks for me, at least on macOS. As I understand it, the performance improvements in the new Quantum engine were incompatible with the way the old extension API worked, so a new one needed to be introduced. To me the tradeoff was worth it, because the increasing sluggishness of FF compared to Chrome, pre-Quantum, was making it harder to stick with.

I don't think anyone denies the performance improvements and other advantages of the Quantum project. The claim is that the transition wasn't handled well, as replacement APIs for the deprecated addon system weren't in place until several releases after Quantum debuted, and several of the more deep-reaching abilities addons had were deprecated completely. This broke many people's workflows, destroying trust.

This also happened a short time after Mozilla previously broke addons with the e10s changes, requiring many (most?) of them to be rewritten.

Basically, people don't trust Mozilla to handle transitions well any more, even when they happen to be worthwhile transitions.

This was my exact experience as well. I had to kill/restart FF every few days because it would randomly start eating CPU (this was on Win 10). Because of this I used Chrome until they disabled back navigation via backspace and forced alt-left instead. This pissed me off enough to try FF again, which was right around when Quantum came out. I've never looked back.

Did they "break" - ie some bug caused a problem - or did they change the framework add-ons used after giving months of notice? Most users use no add-ons, and wouldn't notice the change, and many of those who do were aware of this ahead of time even if the add-on developers were slow to wake up to the reality.

Exactly, months. Likes that's enough time to completely rewrite your extension using an half-baked replacement. To name a few, Cookie-Autodelete [1] had to wait 7 months to get an API to clear the LocalStorage; noscript [2] lost tons of functionality and will probably never recover;

[1]: https://github.com/Cookie-AutoDelete/Cookie-AutoDelete/issue...

[2]: https://www.ghacks.net/2017/12/01/noscripts-rating-drops-aft...

> Did they "break" - ie some bug caused a problem - or did they change the framework add-ons used after giving months of notice?

It's not clear what you're asking. Mozilla changed the add-on API, and the new API does not have all the features that the old API had. Two add-ons that I liked very much died during the switch.

> Most users use no add-ons

Do you have the data for this? I know I live in a techie bubble, but it sure doesn't fit with my experience or the experiences of others I know who talk about it.

Firefox Public Data Report: https://data.firefox.com/dashboard/usage-behavior

"Has Add-on" has been between 33-38% for the last two years.

And a very good chunk of those (most I'd say) is only running some form of ad blocking.

This is an old post, but in 2009 about 1/3 of FF users had extensions installed. https://blog.mozilla.org/addons/2009/08/11/how-many-firefox-... Without newer data, you'll have to guess whether the new addon model increased or decreased that fraction.

> after giving months of notice?

48 months.. 2 years of notice

Kiwi Browser (Chromium-based) runs Nano Adblocker and uBlock Origin with full support (like on Firefox)

Thanks! I'm investigating it and sadly it seems a bit stale with last commit made 5 months ago: https://github.com/kiwibrowser/android

For browsers this seems like a bit too long without updates. I can imagine maintaining such project is demanding but hopefully the project can gain more attention now with the new version of Firefox breaking extensions on Android.

Last I checked Kiwi is not open source. There are bits and pieces of code lying around in the Github repo, but not the full source code.

The browser seems to get regular enough updates on play store, has decent ad blocking (at least good enough for my purposes) and to date has the best night mode out of all android browsers I've tried.

No white flashes like I've faced in Firefox for Android. The dark mode applies to the whole of the browser UI.

I use Bromite, Firefox for Android or Fenix mostly equally during the day and Kiwi at night.

Though the fact that it is not open source may put some people off.

There are almost daily builds on Discord if you want to join