[webkit-dev] Request for position on First-Party Sets

Wed Apr 14 22:18:38 PDT 2021

Hi R. Niwa,

Thanks for your response.

I should clarify that my interpretation of WebKit's latest position wasn't
solely based on that comment I linked to (which now that you mention, is
worded a bit ambiguously); but also based on discussions that happened on
PrivacyCG calls. As one example, we received a feature request that is
documented in https://github.com/privacycg/first-party-sets/issues/28

As I mentioned, the two specific pieces of feedback from Maciej are still
open issues (https://github.com/privacycg/first-party-sets/issues/20,
https://github.com/privacycg/first-party-sets/issues/29), and we'd like to
hear from you on what a satisfactory resolution may look like for the
WebKit team. Unfortunately, neither of the issues has a
straightforward/trivial solution, and PrivacyCG discussions have been
spirited, but I'd also like to invite browsers, and ecosystem stakeholders
for advice.

The reason I am inviting the Webkit team specifically is because my
understanding from Maciej's previous response and his support for
incubation within the PrivacyCG is that the team acknowledges that the
problem itself is worth solving.

Best,
Kaustubha

---
From: Ryosuke Niwa <rniwa at webkit.org>
Subject: Re: [webkit-dev] Request for position on First-Party Sets

On Tue, Apr 13, 2021 at 1:52 PM Kaustubha Govind via webkit-dev
<webkit-dev at lists.webkit.org> wrote:
>
> [Resending after subscribing to webkit-dev, since my previous message
bounced back]
>
> On Tue, Apr 13, 2021 at 4:47 PM Kaustubha Govind <kaustubhag at chromium.org>
wrote:
>>
>> Hi Maciej, Webkit team,
>>
>> Now that First-Party Sets has been incubating within PrivacyCG for ~6
months, I wanted to check with you to see if you have reconsidered your
position on the proposal. It seems WebKit may intend to use First-Party
Sets relationships to apply to browser policies other than cookie blocking (
https://github.com/w3ctag/design-reviews/issues/342#issuecomment-801517385),
but I wasn't sure whether to construe that as positive progress in your
position.

I'm not certain in what way John's comment could be interpreted like
that but WebKit does not have such a plan and Apple's WebKit team
continues to oppose this proposal. I don't think there has been
substantive changes to address the various concerns we have raised so
far.

- R. Niwa

On Tue, Apr 13, 2021 at 4:52 PM Kaustubha Govind <kaustubhag at chromium.org>
wrote:

> [Resending after subscribing to webkit-dev, since my previous message
> bounced back]
>
> On Tue, Apr 13, 2021 at 4:47 PM Kaustubha Govind <kaustubhag at chromium.org>
> wrote:
>
>> Hi Maciej, Webkit team,
>>
>> Now that First-Party Sets has been incubating within PrivacyCG for ~6
>> months, I wanted to check with you to see if you have reconsidered your
>> position on the proposal. It seems WebKit may intend to use First-Party
>> Sets relationships to apply to browser policies other than cookie blocking (
>> https://github.com/w3ctag/design-reviews/issues/342#issuecomment-801517385),
>> but I wasn't sure whether to construe that as positive progress in your
>> position.
>>
>> The specific issues that were previously pointed out by Maciej have open
>> issues on the repo, which I would welcome your feedback on:
>> * "Bad faith claims" should be caught during the policy verification
>> process. Relevant issue is
>> https://github.com/privacycg/first-party-sets/issues/20
>> * "500 domains" problem should be addressed by thinking about how we can
>> limit the size of sets (e.g. numeric limits vs. storage/entropy limits):
>> https://github.com/privacycg/first-party-sets/issues/29
>>
>> If you see any other outstanding issues, please feel free to open an
>> issue on the repo, and optionally add the "agenda+" label for discussion on
>> a PrivacyCG call.
>>
>> Thank you,
>> Kaustubha Govind, Chrome
>>
>>
>>
>>
>> On Thu, Jun 4, 2020 at 4:27 AM Maciej Stachowiak <mjs at apple.com> wrote:
>>
>>>
>>>
>>> On Jun 3, 2020, at 5:21 PM, Kaustubha Govind <kaustubhag at chromium.org>
>>> wrote:
>>>
>>> Hi Maciej,
>>>
>>> Thanks for feedback.
>>>
>>> We had previously started the incubation process in WICG, and it was
>>> just moved there: https://github.com/WICG/first-party-sets
>>>
>>> In addition, I have also filed a Proposal Issue in PrivacyCG:
>>> https://github.com/privacycg/proposals/issues/17
>>>
>>>
>>> Thanks! I expressed support for the above proposal.
>>>
>>>
>>> Regarding your concern about preventing (a) Bad faith claims, and (b)
>>> The “500 domains” problem. These are absolutely cases that we would
>>> consider "unacceptable sets", and our initial thinking was that this would
>>> be covered by the "UA Policy" and be subject to review during the
>>> acceptance/verification process. In this version of the proposal, we
>>> attempted to build maximum flexibility for UAs; but it has since become
>>> clear that browsers find this problem worth solving, and also deem it
>>> important to agree on a common policy. We are currently working on an
>>> initial draft of a policy, and will bring that for discussion when ready.
>>>
>>>
>>> That sounds like a positive development, looking forward to it.
>>>
>>>
>>>
>>> Kaustubha
>>>
>>>
>>>
>>>
>>>
>>> On Wed, May 27, 2020 at 3:16 PM Maciej Stachowiak <mjs at apple.com> wrote:
>>>
>>>>
>>>> (1) I notice that this proposal still exists only in a random personal
>>>> repo. Could it please be contributed to an appropriate standards or
>>>> incubation group? Privacy CG would almost certainly welcome this, and I’m
>>>> sure it would be easy to move to WICG as well. There doesn’t seem to be a
>>>> reason to keep the proposal in this “pre-incubation” state.
>>>>
>>>> (2) As discussed in the Privacy CG Face-to-Face, there are two key
>>>> problems to solve with First Party Sets or any similar proposals:
>>>> (a) Bad faith claims. How to prevent domains that are not actually
>>>> owned and controlled by the same party from making claims of being related?
>>>> For example, an ad network could get its top publishers to enter an
>>>> association to regain a certain level of tracking powers.
>>>> (b) The “500 domains” problem. If a first party owns domains that
>>>> aren’t obviously related and that appear to different and distinct brands
>>>> to the user, then the user won’t expect to be tracked across them. (Problem
>>>> named such because of a party known to have hundreds of domains that mostly
>>>> appear to be totally distinct brands). Users would expect both transparency
>>>> and control over this.
>>>>
>>>> The explainer does not really give solutions to these problems. Rather,
>>>> it defers entirely to each individual browser to define a policy to solve
>>>> these problems. Deferring to individual browsers on such key points is
>>>> problematic in a few ways:
>>>> (i) It doesn’t seem right for a proposed web standard to solve only the
>>>> easy problem of syntax, and leave the hardest technical problems of
>>>> semantics to each browser separately.
>>>> (ii) Deferring in this way is bad for interop.
>>>> (iii) It’s not entirely clear if there exists any policy that suitably
>>>> addresses these problems. By only speculating about policies, the explainer
>>>> fails to provide an existence proof that it is implementable.
>>>> (iv) If sites come to depend on First Party Sets for correct behavior,
>>>> there is a risk that every UA will have to adopt a policy that’s the most
>>>> permissive of any, or that copies the most popular UA, for the sake of
>>>> compatibility. Thus, leaving this open may not in fact provide a useful
>>>> degree of freedom.
>>>>
>>>> Given these issues, I don’t think we’d implement the proposal in its
>>>> current state. That said, we’re very interested in this area, and indeed,
>>>> John Wilander proposed a form of this idea before Mike West’s later
>>>> re-proposal. If these issues were addressed in a satisfactory way, I think
>>>> we’d be very interested. It does seem that binding strictly to eTLD+1 is
>>>> not good enough for web privacy features. Driving these issues to
>>>> resolution is part of why we’d like to see this proposal adopted into a
>>>> suitable standards or incubation group.
>>>>
>>>> Regards,
>>>> Maciej
>>>>
>>>>
>>>> On May 27, 2020, at 9:33 AM, Lily Chen <chlily at chromium.org> wrote:
>>>>
>>>> Hi WebKit-dev,
>>>>
>>>> We are requesting WebKit's position on the First-Party Sets proposal as
>>>> described in the explainer [1]. Feedback [2] was provided on a previous
>>>> version of the proposal, which has since been revised. The TAG review
>>>> thread is here [3].
>>>>
>>>> Thanks!
>>>>
>>>> [1] Explainer: https://github.com/krgovind/first-party-sets
>>>> [2] Previous feedback:
>>>> https://github.com/krgovind/first-party-sets/issues/6
>>>> [3] TAG review: https://github.com/w3ctag/design-reviews/issues/342
>>>> _______________________________________________
>>>> webkit-dev mailing list
>>>> webkit-dev at lists.webkit.org
>>>> https://lists.webkit.org/mailman/listinfo/webkit-dev
>>>>
>>>>
>>>>
>>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.webkit.org/pipermail/webkit-dev/attachments/20210415/570e313a/attachment.htm>