Mozilla launches multi-process test in Firefox Beta

Martin Brinkmann
Dec 21, 2015
Updated • Dec 21, 2015

Electrolysis, or multi-process Firefox, is without doubt one of the biggest projects ever for the Firefox development team.

The main idea behind the project is to separate browser code from website content by separating them using multiple processes. Security features such as sandboxing may be implemented at a later point in time as they rely on multi-process Firefox.

The loading and display of web pages is unaffected by the project while Firefox users and add-ons may be affected by it depending on the add-ons that are installed in the browser and how Firefox is being used.

Mozilla implemented Electrolysis in Firefox Nightly some time ago, and made it available in the Developer Edition of the web browser after a while as well.

Firefox Beta Multi-process test

firefox multi-process test

The next step in the release process is to move Electrolysis to the Beta channel. Mozilla launched an A/B test of multi-process Firefox for Firefox Beta a couple of days ago.

About 15% of all Firefox Beta users take part in the experiment. Electrolysis has been activated for half of those selected versions of Firefox while the other half is a control group with Electrolysis disabled.

The organization wants to measure the effect of multi-process Firefox, and while the Telemetry Experiments page does not reveal what's measured exactly, it likely includes information about crashes, hangs, performance, add-on issues, use-time and other metrics that are relevant in answering whether Electrolysis is ready to be distributed to all Firefox Beta users.

Mozilla postponed the release of Electrolysis several times already. The current plan is to release multi-process Firefox to the stable channel on April 19, 2016 when Firefox 46 is released to the stable channel.

This is a projected release date only however and it is possible that Electrolysis will be delayed further.

One interesting idea that Mozilla has to make the release less painful for users of the browser is to enable Electrolysis only in versions of Firefox without add-ons, and in versions of Firefox where only compatible add-ons are installed in.

This would give add-on developers additional time to make their add-ons compatible and make the move to a multi-process Firefox less problematic for users who rely on add-ons that are not compatible.

Interested users find the state of multi-process compatibility of hundreds of Firefox add-ons on the Are We e10s Yet website. (via Sören Hentzschel)

Now You: Are you looking forward to a multi-process Firefox?

Mozilla launches multi-process test in Firefox Beta
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Mozilla launches multi-process test in Firefox Beta
Mozilla launched a Firefox multi-process test recently that tests Electrolysis in Firefox Beta versions.

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  1. barnassey said on February 16, 2016 at 4:45 am

    Im running firefox 45 beta and the checkbox under general is not showing up. Any way to enable this?

  2. Don Gateley said on December 22, 2015 at 11:25 pm

    Hey, Soren, how about an add-on that reports the state of installed add-ons relative to Electrolysis?

  3. Don Gateley said on December 22, 2015 at 11:21 pm

    Soren, what does “shimmed” mean?

    1. Sören Hentzschel said on December 22, 2015 at 11:30 pm

      Shims are compatibility layers to make add-ons (or let’s say parts of add-ons) “compatible” which are not compatible. The shims will be removed a few months after the general availability of e10s. It’s better not to rely on shims because shims are only temporary and bad for the performance.

  4. Dany said on December 21, 2015 at 8:44 pm

    man, people love to bitch on firefox & mozilla about everything these days, & still keep using it. Fair enough if you moan about some bad decisions mozilla have made recently (pocket integration & hello) but imo electrolysis & sandboxing both would be very welcome features for FF in 2016 and are long overdue. XUL removal will also be good in long term.

    1. Adevertiser said on December 22, 2015 at 8:59 pm

      For me Firefox remains the best browser specially for its wide possibility of settings and add-ons. Never considered to change with Chrome. However if Firefox is great thanks to add-ons developers maybe it have to regards a little bit more and go hand to and with them.
      I spent time yesterday to do a clean install without Mozbackup to hope my search bar settings add-ons working again; and another time today to configure again the remaining settings and exclusion list (ie this blog with ublock and noscript for ADW to support it). And my Search-Site add-on icon still missing.
      I’m a basic user in the world of informatics at the same of most people who using PC. If often there’s something changed and I’ve to lost time to disable that function, verify why that add-on stops working, install another add-on to return with previously interface, use ConfigFox to correct some settings or something else… This is not good.
      I would become a Palemoon user without CTR for example since Australis. Firefox have to be Firefox not see other competitors.
      Hovewer always I’ve have to thanks to Firefox developers for this browser.

  5. Pd said on December 21, 2015 at 5:30 pm

    2016 is likely to be a year of great pain for all those who support mozilla. The company made an enormously brave/bad decision to take on a duopoly market that already had many years had start and predictably failed. Don’t be fooled by the attempt to spin the death of Firefox OS as a ‘pivot’ towards some IoT scenario. The company bet their future on fOS at the expense of it’s cash cow and raison d’ etre: Firefox the browser.

    The market for browsers was and is still big enough for Google to enter it and take control when they couldn’t get Mozilla to go in the direction they wanted them to. You don’t see them trying to convince users that Chrome OS, essentially the same concept as Firefox OS, was a legitimate alternative to Android.

    The plan to enable e10s only for generic users completely contradicts the primary remaining unique feature of Firefox: it’s tweaking support. With one hand at Mozilla wanting to cut that back anyway, just at the time when MS is expanding the ability to tweak it’s browser, to likely hitherto unheard of lengths, the other hand is also butchering this advantage by failing to solve the e10s addon compat problem, or shifting responsibility for that issue to unpaid addon developers, a full 6 years after Google entered the bloody market with multi-process as a foundation feature!

    I agree with the tactic but let’s not deny that it’s a desperate measure designed to cause minimum disruption for piecemeal benefit. After all I’d hate to be in Mozilla’s marketing team when the bosses come in and tell them “e10s is finally here, kinda. We need you to magically pimp the feature as it’s our last roll of the dice before irrelevancy, … But, wehhll … You need to only pimp it softly enough so that our loyal tweaking users don’t hear that they will have to wait even longer, 2017 I’d you’re lucky, before they get the feature”.

    Fingers crossed. The world needs three genuine different, competitive browsers. But sheez, Mozilla’s really got some serious repair work to do in 2016. They haven’t done much right for quite some time and what they did do well, such as fix memory management, was well overdue before it even started.

    I write this only with a great mixture of frustration and concern as Firefox is still a very good browser and e10s has to be integrated smoothly or it’ll just be headed in the dodo direction and become another opera.

  6. michal said on December 21, 2015 at 3:48 pm

    Could anyone please tell what’s are the benefits of this? As far as I know (and see) using chrome, opera, vivaldi and now FF leads to much higher memory consumption. I hear “safety” – really, is it easier for developers to make it safer?

    1. Jason said on December 21, 2015 at 6:06 pm

      There are both performance and security benefits in separating web content from the browser. The performance benefit is that the various processes can be run on different cores of the CPU to spread the workload. The security benefit is that malware on websites is less likely to affect the browser itself or to get beyond the browser to the system, because the web content processes can be sandboxed (i.e. their access to the system can be heavily restricted).

      Electrolysis is probably the one major change to Firefox next year that I actually welcome. It’s a good idea, and long overdo. However, it remains to be seen if Mozilla will bungle its implementation…

  7. Advertaiser said on December 21, 2015 at 3:38 pm

    For me it would be enough to have like two days ago a full working search bar with my add-ons. And there is a new trick to disable all these plugin-container.exe?

    1. Advertaiser said on December 21, 2015 at 3:58 pm

      “Classic search” —> “Search-Site add-on icon”

  8. jimbo said on December 21, 2015 at 3:14 pm

    The ONLY thing I’d look forward to (for one who cannot recall last time Ff crashed) would be to launch Bookmarks and SEE all these Keywords I lovingly created over the years …

  9. arghwat said on December 21, 2015 at 12:54 pm

    For me it shows “Complete 50 days ago”, and now I cannot enable e10s because of “accessibility” :/

    1. Sören Hentzschel said on December 21, 2015 at 3:41 pm

      > and now I cannot enable e10s because of “accessibility” :/

      That’s because of See for a few things that can cause this.

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