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Does this release actually enable Fission (process separation) by default? [1] I see it's still turned off in about:config

[1]: https://hacks.mozilla.org/2021/05/introducing-firefox-new-si...

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Fission site isolation is not enabled by default in Firefox 94. Since this is a huge change, it's being slowly rolled out to all Firefox 94 users over the next four weeks to watch for bugs. It's already been enabled for 60% of Firefox Nightly users and 40% of Firefox Beta users for a few release cycles.

It would be nice if the release notes could be updated to say that. Right now it says

> To better protect all Firefox users against side-channel attacks such as Spectre, we’ve introduced Site Isolation. We’ve got your back...errr...side!

I'll ask to update the release note.

To answer my own question: it doesn't, at least not on my system.

I can see the Firefox child process count maxing at around 10 processes with the default fission.autostart set to false:

> ps aux | grep "firefox.*childID" | wc -l

> 10

Also the about:processes page shows some processes containing 'Shared tabs'.

As soon as I flip fission.autostart to true it creates proper separate processes for each tab with the above ps aux command increasing the count as I open up tabs.

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