Changes

Fission is the Mozilla's project to implement Firefox site isolation: third-party iframes will be loaded in separate processes, safely sandboxed from the web page's content process. The primary motivation is to protect against side-channel attacks like Spectre and Meltdown.

Fission is still in active development, and can only supported be enabled in the Firefox Nightly channel and requires WebRender be enabled!.

# Enable the ''"fission.autostart"'' and pref in Nightly using ''"gfx.webrender.all"about:config'' prefs in Nightly. Do not No need to mess with any other ''"fission.*"'' or ''"gfxprefs.webrender.*"'' prefs!

# Fission should now be enabled. To verify it's enabled, mouse load a webpage, hover over a the tab and look , looking for a "[F]" (i.e. Fission) in the tab's tooltip popup.# When If you encounter an issue while using Fission , it is enabled, you can possible to open a non-Fission fission window within the same browsing session using the "File > New Non-Fission Window" item in the hamburger menu item. This is handy for testing whether a bug is specific can be useful to determine if issues are Fission -specific, or notto work around fission-specific breakage.# To disable FissionIn general, reset the avoid modifying other ''"fission.autostart*"'' prefs, as they are often for testing, or unstable features very early in development, and aren't ready to be used for day-to-day browsing. To disable Fission, reset the ''"gfxfission.webrender.allautostart"'' prefs pref to ''"false"'' and restart Nightly.