Firefox Electrolysis (multi-process) won't come out this year

Martin Brinkmann
Nov 27, 2015
Updated • Nov 28, 2015

Firefox Electrolysis, a new multi-process architecture of the browser also known as e10s, won't see a release in stable Firefox this year.

Mozilla announced back in early 2013 that it was considering reviving the multi-process architecture project for Firefox, and began work in earnest in late 2013.

It made the project a priority in mid-2014, and things looked for a while as if a release was just around the corner.

Electrolysis was enabled in Firefox Nightly shortly thereafter, and found its way into the Developer Edition of Firefox later as well.

If you check the Electrolysis page on Mozilla Wiki you will notice that multi-process Firefox won't come out this year anymore in the stable version.

In fact, Electrolysis has been postponed to Firefox 45 at the very least. Considering that things have not gone as smoothly as projected, there is a chance that things will be delayed even further than that.

Firefox 45 will be out on March 7, 2016 if nothing major gets in the way. It is unclear as well when the feature will land in Firefox Beta.

So why the delay?

firefox e10s electrolysis

If you check out the main tracking bug for e10s on Bugzilla, you will notice the huge number of depending bugs. While many of those have been resolved already, as indicated by them being struck out, more than 100 bugs are still being worked on by various members of the team.

Not all of the bugs listed on the page have the same priority, and e10s might very well ship with some of them still being in the works.

If you check the core e10s tracking bug, you still find more than 20 bugs open at the time of writing.

A visit to Are We e10s Yet, the site tracking add-on compatibility in regards to multi-process Firefox, highlights that a large portion of Firefox add-ons are not yet compatible with Electrolysis. Among the incompatible add-ons popular extensions such as NoScript, Adblock Plus, Web of Trust, Ghostery, LastPass or Session Manager.

If Mozilla would launch multi-process Firefox today, those incompatible add-ons would either fail to work at all, partially, or would cause other issues in the browser.

Firefox users can help Mozilla test Electrolysis by running Nightly or Developer versions of the web browser. The more feedback Mozilla gets in regards to what is working and what is not the better.

I don't really mind waiting a bit longer for the feature as I prefer it to be compatible with all or at least the majority of Firefox add-ons and features before it is launched. Doing otherwise would certainly be disastrous for the browser.

Now You: Are you waiting for multi-process Firefox? How would you like to see it turn out?

Firefox Electrolysis (multi-process) won't come out this year
Article Name
Firefox Electrolysis (multi-process) won't come out this year
Firefox's new multi-process architecture, known as e10s or Electrolysis, won't find its way in the Stable version of the browser this year.

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  1. me said on February 28, 2016 at 8:00 am

    Will you be able to Stop or Pause tabs? Like you can mute sound on each tab individually. This would help reduce the impact of CPU websites running on the tab other than currently selected.

  2. Ben said on November 30, 2015 at 7:50 pm

    > Now You: Are you waiting for multi-process Firefox? How would you like to see it turn out?
    No. I don’t want it. Because running each tab in a separate process will bloat RAM usage like in chrome, which is completly unusable for me because of this (well I could buy like an additional 50 GB of RAM or so, but I don’t plan to do that).

    The two processes for GUI/websites is ok, but nothing more.

  3. Ray said on November 29, 2015 at 10:34 pm

    I think everyone is overreacting to e10s.

    e10s will just include one additional process and not a process-per-tab model like Chrome (at least for now!). Even though Firefox rarely crashes for me, I’m fine with this.

    1. Hy said on November 30, 2015 at 12:12 am

      If it would be only one additional process, rather than one-process-per-tab, that would be great.

      Would you please provide a link to read more about where you got this information from?

      Everything I’ve read here on gHacks, and on the Electrolysis page on Mozilla wiki, refers to “multi-process architecture” and “multiple processes,” rather than dual-process. And there is actually rather scant information on the Mozilla wiki page about Electrolysis.

      Any additional info you can provide about where you got your information from would be most appreciated. Thanks!

      1. Hy said on November 30, 2015 at 2:46 pm

        In the absence of an answer thus far, I found this on another Mozilla page, entitled “Multiprocess Firefox”:

        “Future versions of Firefox will run the browser UI in a separate process from web content. In the first iteration of this architecture, all browser tabs will run in the same process and the browser UI will run in a different process. In future iterations, we expect to have more than one content process. The project that’s delivering multiprocess Firefox is called Electrolysis, sometimes abbreviated to e10s.”

        It seems from this that only at first will Electrolysis bring only one additional process, but that later there will be more than only one additional process.

        So, will Electrolysis eventually lead to a process-per-tab architecture like Chrome, or not?

        If someone would please clarify if Firefox Electrolysis will lead eventually to a process-per-tab architecture like Google Chrome, Opera, etc., it would be most appreciated! Thanks.

  4. Dan82 said on November 28, 2015 at 7:59 pm

    NoSquint, an extension which allows custom default zoom levels for text and/or the whole page, is incompatible with e10s. The developer has indicated, that he doesn’t have time to work on it, but with the code being open source on GitHub, there’s a chance someone else will take it up. Still, for me this addon is an important cog in the whole, which makes viewing websites a lot more comfortable. Where would I be today without Greasemonkey, Stylish and NoSquint?

    Another potential issue is the memory consumption of the new multi-process Firefox. We know from all other applications of that design, that the memory overhead is huge and this will also negatively impact Firefox. Personally, I’m hoping for an advanced and configurable option for idle tabs or the ability to unload tabs entirely. While I don’t believe that the browser would instantly become unusable to the power user after such a change, the additional memory requirements need to be considered seriously.

    1. Martin Brinkmann said on November 28, 2015 at 10:22 pm

      I think the biggest issue right now in regards to e10s is to get add-on compatibility in order. It would be really problematic if Mozilla would ship e10s if many add-ons would stop functioning properly.

  5. Antonio said on November 28, 2015 at 5:38 pm

    I’m preparing myself for Firefox Electrolysis in the sense that I have unset automatic updates in Firefox.
    I know that the change will be inevitable, but currently I cannot live without my many addons and I will leave them only when I will be forced.

  6. Tom Hawack said on November 28, 2015 at 2:40 pm

    I checked on Mozilla’s Wiki their general explanation of Firefox Electrolysis.

    “The goal of the current Electrolysis project (“e10s” for short) is to render and execute web related content in a single background ‘content’ process which communicates with the main Firefox process via various ipdl protocols. The two major advantages of this model are security and performance. Security improvements are accomplished through sandboxing, performance improvements are born out of the fact that multiple processes better leverage available client computing power. ”

    Security and performance enhancements. What argument against that? I see none. But I admit that the idea of loosing several (many?) add-ons (I run currently 65 Firefox add-ons) bothers me. Consequently I’ll assume this paradox : I’m in no hurry for the deployment of Firefox Electrolysis but at the same time I consider it is welcomed as such. Just like when you know you have a duty planned but you postpone it day after day or, as Corsicans would put it “Today maybe, or tomorrow otherwise …” (lol).

  7. Nebulus said on November 28, 2015 at 10:33 am

    Good. I want a browser that works, not something that implements features just because other browsers have it.

  8. Dwight Stegall said on November 28, 2015 at 8:08 am

    I would love to see Electrolysis released. Firefox has never been stable for me like Chrome is. It would be nice to have another reliable browser that can do things that Chrome can’t or makes difficult.

  9. Xi said on November 28, 2015 at 3:03 am

    @Martin, Please correct the date above the first image. Firefox 45 will be out on March 7, “2016” and not “2015”.

    1. Martin Brinkmann said on November 28, 2015 at 7:41 am

      Done, thanks!

  10. Croatoan said on November 28, 2015 at 1:19 am

    My default browser is Firefox. For me, it’s more stable than Chrome (and less resource hungry).

    Electrolysis is not so important for me.

    1. Jeff said on November 28, 2015 at 2:44 am

      Well said, and I fully agree. It ain’t broke, and doesn’t need fixing.

  11. not_black said on November 28, 2015 at 1:01 am

    It won’t ship with v45 I’m sure, that’s a ESR version, I don’t think they would put such a new “feature” into an ESR version.

  12. Pete said on November 27, 2015 at 11:32 pm

    When, if, it comes out, FF becomes like Chrome, unable to use more than with few tabs. Bye bye powerusers (again.. first it was with good old Opera).

    1. Hy said on November 28, 2015 at 11:57 am

      I have to say I agree completely with Pete. For me, FF and the other Mozilla-based browsers are fine as they are now without this latest Electrolysis “innovation.” And I cringe thinking about all of the processes and resources that will be running, especially for any users who may happen to have more than a small handful of tabs open at once, and also for users who don’t have much RAM or computing power to begin with. I know a great number of folks who are getting by on only 4GB RAM at the most. I’ve been running 16GB RAM for some time, so I’m not worried about not having the resources myself, but I still won’t appreciate the extra unnecessary load on my system.

      Every user is different, and I know people who can’t stand having more than a very few tabs open, and others who will have a good number open. At any given time, I may have 5, 25, or 100 tabs open, depending on what I’m doing. No matter how many I have open, it never causes any noticeable deleterious effect, unless I would continue to keep opening tabs and not reboot for several days.

      I no longer allow Chrome or anything Google on my machine, but I know from watching it run on other peoples’ systems, and remember from my own testing of it some years back, that it seems to run a separate process for each and every single tab open! This is unthinkable for me given the way I browse sometimes. I know Google’s rationale for this about sandboxing and supposedly making it more stable, but really, if this is the latest Chrome feature which FF wants to emulate, I really wish they wouldn’t. FF has been fine for me for years and years, no matter how many tabs I have open. I find Google’s “stability” excuse to be a red herring here—I don’t find Chrome or other Chromium-based browsers to be any more “stable” than FF; in fact, as I said, I have never found FF to be “unstable.”

      I have, however, found Google Chrome and other Chromium-based browsers which emulate it, such as Opera, to be slower and just generally more unwieldy-feeling sometimes, and also to eat a great deal of RAM and just generally give me the impression of overburdening the system overall. Running the Chromium/Blink-based Opera, it is unimaginable for me to have as many tabs open in it as I can have open in Firefox. This latest Electrolysis “innovation” seems inevitable, if still far off, and until I am convinced otherwise, I hope somewhere along the way Mozilla miraculously abandons this latest “Chrome-ification” of Firefox.

      1. Brad V said on January 5, 2016 at 2:15 am

        The whole idea of true multi-process browsers like chrome and edge is to prevent exactly what you guys believe happens when you use chrome. Assigning each tab it’s own separate process may look terrifying when you open task manager, but it’s actually a good thing. Running each tab as a separate process prevents any one tab from ‘bogging down’ the others. The only limitation the becomes your memory size and processing power.

        I’m not sure what systems you guys run but if you’re getting anything other than the smoothest, most memory efficient experience using chrome then I suggest you look at your system rather than chrome. I’m a long time FF user, and until recently hated Chrome. Honestly, I still use it begrudgingly. Nothing compares to the almost infinite flexibility of FF. Unfortunately if I ever need to open 40, 50+ tabs FF (even the first multi-process iteration) is just not an option. Even when showing more than enough memory available, FF (public release, developer, nightly) is very noticeably slowed when opening a lot of tabs. It’s fine up to about 20 or so, but keep going and you will feel it. On the other hand, 50 tabs in chrome feels almost exactly the same as 1. Occasionally there is some measurable difference, such as reloading many tabs at once, but this is the same with other browser, just worse.

        I’ve run extensive back to back to back tests of Firefox, Chrome, and Edge, and Chrome is hands down the most memory efficient of the three. I hate admitting that, but I can’t deny the facts just cos I hate google and Chromes lack of flexibility. Initially Edge was comparable, or even better, but lately I’ve noticed processes bloat over time, unlike Chrome.

        But believe me, I can’t wait til Firefox get full multi process working. I’ll never have to open chrome again :)

      2. LimboSlam said on November 29, 2015 at 9:07 am

        @not_black: Well, in my personal experience, Firefox itself is unstable no matter what stage or title Mozilla gives it. Yes that means the stable version which I also have been testing, toggling browser.tabs.remote.autostart.

        So at least with Pale Moon it’s stable enough to use for daily hardcore use. This is of course is my personal opinion and experience here.

      3. not_black said on November 29, 2015 at 1:49 am

        “Developer Edition” is just a shitty name, it is not intended for developers. It’s just a pre-beta version. It’s almost as buggy and unstable as the nightly.

      4. LimboSlam said on November 28, 2015 at 9:23 pm

        Agree, I’m currently testing Firefox Developer version and all I get is hangs and half working add-ons with e10s. This is not good for power users (like me) who love to test/use lots of add-ons with a bunch of open tabs, twenty is the max for me. Of course I’m using an older laptop (Dell Latitude D630c with 3.00GB of RAM) with an older OS installed, Vista. Funny though, I never have this much hangs with Chrome as I do with Firefox. Well that’s just the bleeding edge of Firefox I’m testing. But the fact is, power users are a thing of the pass for Firefox.

        Now Pale Moon gives me no problems with all the open tabs I have and hard core add-ons I’m currently using. Not to mention flexible customization. So I would recommend Pale Moon if your a power user or just experience lots of issues with the new Firefox, Chrome-ification of Firefox.

  13. Dave said on November 27, 2015 at 11:08 pm

    That’s fine. Firefox is fine.

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