Hey all! It's been a while (7 months!) since the first Fission newsletter, but we've made some exciting progress we'd love to tell you about!
Enabling Fission on Nightly It's now possible to turn on Fission in nightly builds of Firefox by setting fission.autostart pref to true. Fission can also be enabled for running tests using mach test … --enable-fission. When Fission is enabled, each cross-site iframe is loaded in a different content process, meaning lots of different processes participate in drawing a single tab. The hover tooltip for a Fission-enabled tab is annotated with a "[F …]" containing a series of process IDs, as shown in the image below, serving as a visual verification of an active Fission-enabled session. We currently do not recommend trying to use Fission for day-to-day browsing, as there are still known stability issues. However, if you do try it out, please file bugs/issues blocking fission-dogfooding <https://bugzilla.mozilla.org/show_bug.cgi?id=fission-dogfooding>. Fission Mochitests on mozilla-central Fission Mochitests were recently enabled as tier-2 jobs on mozilla-central. This will allow us to run tests with Fission enabled on infrastructure, and prevent landing new features or code which don't support Fission. Tests which do not currently successfully pass are marked as fail-if = Fission or skip-if = Fission. We'd love your help migrating tests to run with Fission enabled! Here are a couple of handy tips for making your test Fission-compatible: 1. Use SpecialPowers.spawn(target, [args…], async (args…) => { … }), to run code in potentially cross-origin iframes, as they may be in a different process. This API is similar to the ContentTask.spawn API used by browser-chrome mochitests. 2. Wait for document loads to complete before trying to run code inside the target window, as a process switch may occur after the frame or browser is created. For frames in content, this usually means waiting for the load event. These tests may also be run on the tryserver, however they are currently excluded from the default set. They are called M-fis, and can be found in ./mach try fuzzy --full. Fixing these Mochitests is a goal of our next major milestone, M4! There's a ton of awesome stuff happening in M4, which you can read about on the wiki (https://wiki.mozilla.org/Project_Fission#M4_goals). Fission Talk and Demo At the 2019 Whistler All-Hands, Nika gave a talk & demo about the Fission architecture. This talk is publicly available on Air Mozilla. You can watch the talk here: https://onlinexperiences.com/Launch/Event.htm?ShowKey=44908&DisplayItem=E334923 The slides are here: https://docs.google.com/presentation/d/1equyaJTujM4xF-ucoMZiLE-lo0lbHKFMliUfPE4_1B8/edit?usp=sharing And… So Much More! A ton has happened in Fission over those 7 months, and it would be impossible to cover all of the awesome work everyone has been contributing to make Fission happen. We just want to say a massive thank you to everyone who has helped with Fission - writing patches, doing reviews, planning, and more! We hope to do brief update newsletters like this one with a better cadence, so hopefully there'll be another one of these in your inbox soon. Let's keep fission-on! - The Fission Team. _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform