> While Storage Access Headers <https://groups.google.com/a/chromium.org/g/blink-dev/c/gERgwZfN_-E> was recently shipped, we would like to allow more time for the ecosystem to adopt this new API and provide feedback on whether SAH satisfies their use cases (see example discussion <https://github.com/prebid/Prebid.js/issues/12729>). This would help reduce the impact of deprecating the labels when the experiment ends.
Storage access headers make it difficult for a publisher to ascertain if some generic third party would receive none or active on their request without inducing network traffic to some third parties and asking for the results to be reflected. This is rather annoying to the publisher, as it requires it to induce network round trips before deciding, for example, should it initiate a PA API auction bc the cookies are missing. as the DV360 team suggests to the Prebid.js team here: https://github.com/prebid/Prebid.js/issues/12729. On Wednesday, April 30, 2025 at 11:46:05 AM UTC-4 Jxck wrote: > What is the motivation for 3rd Parties to experiment Privacy Sandbox, > Storage Access API etc etc alternates 3rd Party Cookies from point of view > of Chrome's vision change ? > > On Tuesday, April 29, 2025 at 11:48:05 PM UTC+9 Nan Lin wrote: > >> Contact emails >> >> lin...@chromium.org, jka...@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, and we want to avoid >> disruption while we engage with the industry to gather feedback on an >> updated roadmap for these technologies. Therefore 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. >> >> Storage Access Headers >> <https://groups.google.com/a/chromium.org/g/blink-dev/c/gERgwZfN_-E> was >> shipped in M133, allowing developers to determine if they have access to >> unpartitioned cookies via the Sec-Fetch-Storage-Access header instead of >> labels. See detect third-party cookie availability in Chrome >> <https://privacysandbox.google.com/cookies/prepare/detect> for details. >> Extending this experiment gives time for developers to adopt this recently >> shipped API as a signal for cookie access and provide feedback. >> >> >> 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 >> >> >> https://groups.google.com/a/chromium.org/g/blink-dev/c/TCP6aAFnS4I/m/XXYIMqC6AQAJ >> >> >> >> Goals for experimentation >> >> Continued deployment and evaluation of Privacy Sandbox Ads APIs. >> >> Experimental timeline >> >> This feature was previously approved to run up until Chrome 135. >> >> We would like to extend this for Chrome 136 through 138, inclusive. >> >> Any risks when the experiment finishes? >> >> Minimal, the cookie deprecation labels are only available for a subset of >> users and must be requested. >> >> As new clients are ineligible for the experiment, the percentage of >> clients that receive the labels will decay over time, and eventually the >> experiment would effectively expire naturally. >> >> 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, and we want to avoid >> disruption while we engage with the industry to gather feedback on an >> updated roadmap for these technologies. >> >> While Storage Access Headers >> <https://groups.google.com/a/chromium.org/g/blink-dev/c/gERgwZfN_-E> was >> recently shipped, we would like to allow more time for the ecosystem to >> adopt this new API and provide feedback on whether SAH satisfies their use >> cases (see example discussion >> <https://github.com/prebid/Prebid.js/issues/12729>). This would help >> reduce the impact of deprecating the labels when the experiment ends. >> >> 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/2fc68503-6d6a-4e41-8970-8324ee6628c1n%40chromium.org.
