Disable FLoC in Brave

[pes10k]

Currently Brave disables the FLoC component. However there is other FLoC functionality shipped in Chromium (behind origin trials). We should disable FLoC completely in Brave, including:

1. FLoC client-side determinations of cohorts
2. Any reporting of FLoC cohort determinations to Google (or otherwise) servers (i.e., the reporting used for k-anonymity cohort protections)
3. FLoC JS methods (i.e. document.interestCohort)
4. Any UI related to the FloC permission (i.e., interest-cohort)

[iefremov]

@pes10k
can you please provide more details on "Any UI related to the FloC permission (i.e., interest-cohort)" - I haven't spotted any related UIs

[pes10k]

Sounds good, if there is no UI, then happy for that part to be a NOOP.

The explainer doc just says there is there will be a new permission, and so the request was to disable any UI (for example, any content setting control) related to that permission. But if that doesn't exist, then, even easier!

[kjozwiak]

Adding this into the 1.25.x as it landed via brave/brave-core#8468.

[ElijahLynn]

For those wondering what FLoC is like I was:

• Federated Learning of Cohorts (FLoC)
• https://github.com/WICG/floc
• https://www.eff.org/deeplinks/2021/03/googles-floc-terrible-idea

[stephendonner]

Verified FIXED using nightly build

Brave	1.25.11 Chromium: 90.0.4430.61 (Official Build) nightly (x86_64)
Revision	dced74d4124b26b14126b611853d33512b60c7b6-refs/branch-heads/4430@{#1115}
OS	macOS Version 11.2.3 (Build 20D91)

Using the steps from brave/brave-core#8468:

1. went to brave://components and ensured there's no Federated Learning of Cohorts component

2. opened the devtools console, typed `document.interestCohort()` and confirmed that I got an error:

---

Verification passed on

Brave	1.25.59 Chromium: 90.0.4430.212 (Official Build) beta (64-bit)
Revision	e3cd97fc771b893b7fd1879196d1215b622c2bed-refs/branch-heads/4430@{#1429}
OS	Ubuntu 18.04 LTS

Verified test plan from brave/brave-core#8468

1. went to brave://components and ensured there's no Federated Learning of Cohorts component
   

2. opened the devtools console, typed document.interestCohort() and confirmed that I got an error:
   

---

Verification passed on

Brave | 1.25.60 Chromium: 90.0.4430.212 (Official Build) beta (64-bit)
-- | --
Revision | e3cd97fc771b893b7fd1879196d1215b622c2bed-refs/branch-heads/4430@{#1429}
OS | Windows 10 OS Version 2004 (Build 19041.985)

• Verified the test plan from 14942: Disable FLoC features and the provider service. brave-core#8468

1. went to brave://components and ensured there's no Federated Learning of Cohorts component
   

2. opened the devtools console, typed document.interestCohort() and confirmed that I got an error:
   

[srirambv]

Verification passed on OnePlus 6T with Android 10 running 1.25.51 x64 Beta build

• Verified test plan from 14942: Disable FLoC features and the provider service. brave-core#8468

---

Verification passed on Samsung Tab A with Android 10 running 1.25.51 x64 Beta build

• Verified test plan from 14942: Disable FLoC features and the provider service. brave-core#8468

[dentistformyeye]

A yellow warning shows up in the browser console when I go to https://web.archive.org/. I'm not sure whether this means there's still something that could be removed or whether this message is supposed to appear.
Error with Permissions-Policy header: Unrecognized feature: 'interest-cohort'.
If it doesn't appear at first, refreshing the page might make it show up.

On a page archived on the Wayback Machine such as this, the yellow warning can show up twice.

I'm on Brave version 1.25.68 (Chromium: 91.0.4472.77).

[pes10k]

Hi @dentistformyeye , thanks for the comment, but what you're seeing isn't a bug, its as intended.

Brave removes all FLoC support in the browser. This also removes support for understanding the "disable FLoC" header, which is why you're seeing the message you're seeing in the console. Or, put differently, since Brave doesn't support FLoC, it also doesn't support the "disable FLoC" command. So, you can safely disregard this message, knowing that FLoC isn't enabled.

Hope that helps!