Hi Mike, On Sat, Feb 1, 2025 at 12:50 PM Mike Taylor <miketa...@chromium.org> wrote:
> > On 1/31/25 4:39 PM, Nan Lin wrote: > > > > On Fri, Jan 31, 2025 at 4:35 PM Mike Taylor <miketa...@chromium.org> > wrote: > >> >> On 1/31/25 3:03 PM, Nan Lin wrote: >> >> Hi Mike, >> >> Thanks for the response. >> >> On Fri, Jan 31, 2025 at 11:00 AM Mike Taylor <miketa...@chromium.org> >> wrote: >> >>> Hey Nan, >>> On 1/24/25 6:29 PM, Nan Lin wrote: >>> >>> Contact emails >>> >>> lin...@chromium.org, wanderv...@chromium.org >>> >>> Explainer >>> >>> >>> https://github.com/privacysandbox/tpcd-labeling/blob/main/cookie_deprecation_labeling_explainer.md >>> >>> https://developer.chrome.com/en/docs/privacy-sandbox/chrome-testing >>> >>> Summary >>> >>> The cookie deprecation labels are useful for developers to evaluate and >>> optimize deployments of the Privacy Sandbox APIs prior to any changes in >>> the number of browsers which support third-party cookies, so we are asking >>> to extend the current set of labels >>> <https://developers.google.com/privacy-sandbox/relevance/setup/web/chrome-facilitated-testing> >>> for three more milestones. >>> >>> This is a non-standard experiment, so the areas to demonstrate progress >>> in https://www.chromium.org/blink/launching-features/#origin-trials >>> don't cleanly apply. That said, have you received any useful feedback from >>> developers who are using these labels? >>> >>> Also, when do you expect this experiment to outlive it's usefulness? >>> >> We've heard from developers using the APIs that the current >> implementation of labels remains a useful way to coordinate while there is >> traffic where Chrome has disabled third-party cookies. >> >> Storage Access Headers >>> <https://groups.google.com/a/chromium.org/g/blink-dev/c/gERgwZfN_-E> >>> will ship in M133, allowing developers to determine if they have access to >>> unpartitioned cookies via the Sec-Fetch-Storage-Access header instead of >>> labels. Extending this experiment gives time for developers to make use of >>> this upcoming API as a signal for cookie access. >>> >>> My understanding of this experiment was to allow for A/B testing >>> analysis - but it sounds like it can be replaced with a signal of "has 3P >>> cookies" (like navigator.cookieEnabled). Does that fully satisfy the needs >>> of developers trying to understand PS APIs? Or do I misunderstand? >>> >> >> The goal of this experiment is to allow ad-techs to run server side A/B >> testing from the browser provided treatment and control groups, and >> evaluate the impact of third party cookie phase out. >> It allows ad-techs to continue to test Privacy Sandbox APIs on some >> traffic without population issues. >> >> Thanks - perhaps my question wasn't super clear. Does >> Sec-Fetch-Storage-Access fully replace this experiment to allow for A/B >> testing by ad tech companies? >> > > Thanks Mike for clarifying the question. I don't think > Sec-Fetch-Storage-Access can fully replace this experiment at this stage, > as it doesn't tell whether the third party cookies are disabled by Chrome > or not. > We would still need these labels to allow downstream A/B testing on the > traffic slice with and without third party cookies. > > I see, thanks. I would still like to understand the plan for/answer to my > first question: > > > Also, when do you expect this experiment to outlive it's usefulness? > > I can imagine some ad techs would be happy to receive the labels forever, > if they have some utility today. > > In terms of burn-in risk, do we have any use counter or UMA metrics to > understand its usage (since it's been in the wild for more than a year at > this point)? > The labels are only sent on the traffic slice where Chrome enables mode A (label only) and mode B (third party disabled) experiments, and overall this is <8.5% of browsers (these labels are also subject to a number of eligibility requirements). The labels will not be sent forever, and will be deprecated when Chrome stops the experiments and there is no traffic where Chrome disables third party cookies. Hope that clarifies! > >>> Link to “Intent to Experiment” blink-dev discussion >>> >>> >>> https://groups.google.com/a/chromium.org/g/blink-dev/c/0_dR-ffA2LA/m/ZgmMhK-XAQAJ >>> >>> >>> https://groups.google.com/a/chromium.org/g/blink-dev/c/3escBQGtIpM/m/ntcytva5BgAJ >>> >>> https://groups.google.com/u/1/a/chromium.org/g/blink-dev/c/v3PiIzm1M-Y >>> >>> >>> >>> Goals for experimentation >>> >>> Continued deployment and evaluation of Privacy Sandbox Ads APIs. >>> >>> Experimental timeline >>> >>> This feature was previously approved to run up until Chrome 132. >>> >>> We would like to extend this for Chrome 133 through 135, inclusive. >>> >>> Any risks when the experiment finishes? >>> >>> Minimal, the cookie deprecation labels are only available for a subset >>> of users and must be requested. >>> >>> Reason this experiment is being extended >>> >>> We have received feedback that these labels are useful for ad tech >>> companies to evaluate and optimize the APIs in preparation for changes to >>> third party cookie availability. >>> >>> Ongoing technical constraints >>> >>> None >>> >>> Will this feature be supported on all five Blink platforms supported by >>> Origin Trials (Windows, Mac, Linux, Chrome OS, and Android)? >>> >>> No, not supported on webview. >>> >>> Link to entry on the feature dashboard >>> >>> https://chromestatus.com/feature/5189079788683264 >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "blink-dev" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to blink-dev+unsubscr...@chromium.org. >>> To view this discussion visit >>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/849254f2-1020-46d2-b42a-b7dd02db5e85n%40chromium.org >>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/849254f2-1020-46d2-b42a-b7dd02db5e85n%40chromium.org?utm_medium=email&utm_source=footer> >>> . >>> >>> -- You received this message because you are subscribed to the Google Groups "blink-dev" group. 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