When we run the test in v2 we are expecting to need to update the value in this pref: discoverystream.personalization.modelKey

I don't have the new values quite yet.

https://hg.mozilla.org/mozilla-central/rev/bdc1fb2dfac2

I have verified that the issue is no longer reproducible on Firefox Nightly 74.0a1 Build ID 20200205055433 using Win 10, Linux Ubuntu 16.04 and Mac 10.14.
Value of the "browser.newtabpage.activity-stream.discoverystream.personalization.modelKeys" pref was updated.

[Tracking Requested - why for this release]: Wondering if we can apply this patch to beta too, it's super small.

It'll make the experimentation process easier, because otherwise we would need to set that pref via experiment setup.

Comment on attachment 9123683 [details]
Bug 1612326 - Update model keys pref used for v2

Beta/Release Uplift Approval Request

• User impact if declined: Not much.

It makes experiment setup easier, which in turn causes our experiment to run smoother, less chance for something to break, and less chance for a problematic experience for the users in the experiment.

• Is this code covered by automated tests?: Yes
• Has the fix been verified in Nightly?: Yes
• Needs manual test from QE?: No
• If yes, steps to reproduce: Not really needed, the experience with this change should be exactly the same as without, so maybe some basic regression testing would be nice, but I'm pretty confident it'll be fine based on how simple the changes are.
• List of other uplifts needed: None
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): It's just updating the default value in a pref that's used in an experiment. (it's also the value we use in nightly)

Changing this pref doesn't trigger new functionality unless another pref if switched to true, so doing this change alone doesn't turn on something new.

• String changes made/needed:

Comment on attachment 9123683 [details]
Bug 1612326 - Update model keys pref used for v2

Wrong patch, this was meant for another pref change.

I meant to request uplift for 1615734