Bug 1588050 enabled this on Nightly channel, but it is still disabled on all others.
Now that the Multiprocess Browser Toolbox baked for a while on Nightly, we can probably turn it on on all channels?

https://searchfox.org/mozilla-central/rev/9c6e7500c0015a2c60be7b1b888261d95095ce27/browser/app/profile/firefox.js#1908-1915

Tracking Fission DevTools bugs for Fission Nightly (M6) milestone

Harald, Do you think we are ready to enable the Multiprocess browser toolbox on all channels?

The possible blockers I could be aware of are:

• performance. The MBT is certainly slower than the regular Browser Toolbox. Bug 1605763 and bug 1615236 fixed notable performance issue. Now the MBT may only be slower by the simple fact that it displays more content. More console messages, more sources, ...
• JS Context Selector (bug 1605330, which is about enabling it on Nightly). It isn't really mandatory, but this is a really nice feature to have in the MBT.
• I'm not aware of any particular breakage in the MBT? Nor any notable performance issue really specific to MBT, which isn't just an overload of content to display?

Bug 1615412 may be a blocker

Bug 1615412 may be a blocker

I agree, and the only one I am aware of as well – which is a good sign after having it on Nightly for 2 months. It would be good to have more analysis on bug 1615412 to understand reach/impact. I have not seen the issue for a while but ran into it constantly before and this still seems to apply to Mike & Dão.

performance. The MBT is certainly slower than the regular Browser Toolbox. Bug 1605763 and bug 1615236 fixed notable performance issue. Now the MBT may only be slower by the simple fact that it displays more content. More console messages, more sources, ...

MTB being slower and more powerful should be an acceptable trade off, given its niche audience. It would be good to have an eye on it. I assume MBT performance is reported as part of our existing performance metrics but we can't segment on tab vs browser toolbox as both are reported on thee main process – correct?

JS Context Selector (bug 1605330, which is about enabling it on Nightly). It isn't really mandatory, but this is a really nice feature to have in the MBT.

Agreed that it's nice to have. Hopefully we can follow up to let it ride the trains soon.

Adding Bug 1631718 as a blocker. The MBT can't be opened if you visit a website that uses CSPs.

Tracking dt-fission-m2-mvp bugs for Fission Nightly milestone (M6c)

Bug 1615412 addressed the ipv6 issue. Last comment from bug 1615412 mentioned the pending update breakage (=bug 1120863).
It isn't clear if all reports of broken browser toolboxes are related to pending updates, or if there is still something else.

We might be good to go here.
The ipv6 and pending updates are unrelated to multiprocess.

I'm still concerned about the performance impact of this on the Browser Console and Browser Toolbox on Console,
where it freezes for a few second before you can evaluate anything.

Here is a profile of this:
https://share.firefox.dev/3dTLa8p

Bulk move of all dt-fission-m2-reserve bugs to Fission MVP milestone.

Moving "dt-fission-m3-reserve" bugs to "dt-fission-future" because they don't block Fission MVP.

https://hg.mozilla.org/mozilla-central/rev/ea309c44e712

Nicholas, does this bug need any QA verification for the 106 release work?

(In reply to Henrik Skupin (:whimboo) [⌚️UTC+2] from comment #14)

Nicholas, does this bug need any QA verification for the 106 release work?

I'll play around with the Browser Toolbox on Firefox Beta to see if everything is fine

As discussed in the team meeting Nicolas will run some tests on beta to ensure the feature works as expected.

(In reply to Henrik Skupin (:whimboo) [⌚️UTC+2] from comment #16)

As discussed in the team meeting Nicolas will run some tests on beta to ensure the feature works as expected.

I tested a few features in both parent process and multiprocess mode in Beta, and things seems to work well

Thanks Nicolas!