LGTM1 On Fri, Jun 12, 2026 at 1:18 AM Yao Xiao <[email protected]> wrote:
> Hi API Owners, > > The Topics API was deprecated in Chrome-144 with a plan to remove it in > Chrome-150. Currently the usage is 4.9% of page loads. > > <https://chromestatus.com/metrics/feature/timeline/popularity/5102>We are > proposing the following as next steps for removal and associated timelines: > > 1. M150: Remove all Ads API-related entries from Chrome settings and UI > surfaces (e.g., chrome://settings/adPrivacy) via field trial. After this > point, all API invocations for field-trial enabled browsers will always > reject. Since the API can already be disabled for one of many reasons, > scripts must already handle such rejections (or they’re already > significantly broken). > 2. M152: Permanently remove the underlying implementation code for the > API, and replace it with a lightweight stub API. The stub will remain > removable via field trial. > > 3. M152 Canary/Beta: Begin a controlled rollout of the stub API removal > via a field trial. > 4. M152 Stable: Assuming there are no regressions or breakage after > reaching 1% stable, we will request additional approval for full removal at > this stage. > > At this time, we are seeking LGTMs for steps #2 and #3. > > Thanks, > > Yao > > On Wednesday, November 12, 2025 at 11:36:22 AM UTC-5 Daniel Bratell wrote: > >> LGTM3 according to Vlad's plan. >> >> /Daniel >> On 2025-11-12 17:19, Chris Harrelson wrote: >> >> LGTM2 with the same conditions Vlad mentioned. >> >> On Wed, Nov 12, 2025 at 8:16 AM Vladimir Levin <[email protected]> >> wrote: >> >>> LGTM1 to deprecate. The plan to keep deprecation for 6 milestones also >>> sounds good. Please come back after to this thread at a time when you think >>> the removal can proceed. Since the amount of page loads is extremely high, >>> we would like to reserve the right to pause the removal if this amount of >>> page loads does not decrease substantially. >>> >>> On Friday, November 7, 2025 at 1:12:36 PM UTC-5 Yao Xiao wrote: >>> >>>> Intent to Deprecate and Remove: Topics API >>>> >>>> Contact emails >>>> >>>> [email protected] >>>> >>>> Explainer >>>> >>>> https://github.com/patcg-individual-drafts/topics >>>> >>>> Specification >>>> >>>> https://patcg-individual-drafts.github.io/topics/ >>>> >>>> Summary >>>> >>>> The Topics API is a privacy-preserving web API to enable ad-targeting >>>> based on a person’s general browsing interests, without exposing their >>>> exact browsing history. >>>> >>>> Following Chrome's announcement that the current approach to >>>> third-party cookies will be maintained, we are now planning to deprecate >>>> and remove the Topics API (along with other Privacy Sandbox APIs). >>>> >>>> The following API surfaces will be affected: >>>> >>>> - >>>> >>>> The JavaScript function `document.browsingTopics()` will be removed. >>>> - >>>> >>>> The `browsingtopics` attribute on <iframe> and <img> elements will >>>> be ignored. >>>> - >>>> >>>> The `browsingTopics` option in the fetch() API's RequestInit will >>>> be a no-op. >>>> - >>>> >>>> Consequently, the `Sec-Browsing-Topics` request header will no >>>> longer be sent, and the `Observe-Browsing-Topics` response header will >>>> no >>>> longer be honored. >>>> - >>>> >>>> The "browsing-topics" and "interest-cohort" permissions policy >>>> features will be removed. >>>> >>>> >>>> Blink component >>>> >>>> Blink>TopicsAPI >>>> <https://issues.chromium.org/u/1/issues?q=customfield1222907:%22Blink%3ETopicsAPI%22> >>>> >>>> Web Feature ID >>>> >>>> None >>>> >>>> Motivation >>>> >>>> Chrome has announced that the current approach to third-party cookies >>>> will be maintained. Given this, we expect adoption to decrease over time >>>> (currently at 13% >>>> <https://chromestatus.com/metrics/feature/timeline/popularity/5102> of >>>> page loads) as interest based advertising will remain possible in Chrome >>>> using third-party cookies. Further, other browser engines have not signaled >>>> interest in launching the API. See also the initial public proposal below. >>>> >>>> Initial public proposal >>>> >>>> >>>> https://privacysandbox.com/news/update-on-plans-for-privacy-sandbox-technologies/ >>>> . >>>> >>>> Possible breakage >>>> >>>> Sites that rely on Topics API for targeting will experience utility >>>> impact. >>>> >>>> If usage warrants, we will take steps to avoid any risk of page >>>> breakage, e.g. by temporarily retaining a stub implementation of >>>> `document.browsingTopics()` that mimics current behavior when a user has no >>>> topics to return. However, since Topics is not enabled by default for all >>>> users, sites should already be using feature detection, which makes the >>>> risks of breakage low. >>>> >>>> Debuggability >>>> >>>> N/A >>>> >>>> Requires code in //chrome? >>>> >>>> True >>>> >>>> Estimated milestones >>>> >>>> Deprecate in M144 and then remove in M150. >>>> >>>> Currently, ~13% >>>> <https://chromestatus.com/metrics/feature/timeline/popularity/5102> of >>>> page loads use Topics API. These are driven by a small number of >>>> third-party ad tech scripts present on a large number of sites. We will >>>> continue to monitor usage as well as provide comprehensive updates on >>>> privacysandbox.google.com <http://goo.gle/ps-status> with the status >>>> of the API and deprecation plans. >>>> >>>> We will also proactively work toward reducing usage to a low level once >>>> the intent is approved, including disallowing any new enrollment sign-ups, >>>> and contacting all enrolled sites that use the Privacy Sandbox APIs to >>>> inform them about the deprecation timelines. >>>> >>>> Link to entry on the Chrome Platform Status >>>> >>>> https://chromestatus.com/feature/5135370673061888 >>>> >>>> -- >>> 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 [email protected]. >>> To view this discussion visit >>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/c97119d8-b351-4e2d-b106-c7ea1e4f60ccn%40chromium.org >>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/c97119d8-b351-4e2d-b106-c7ea1e4f60ccn%40chromium.org?utm_medium=email&utm_source=footer> >>> . >>> >> -- >> 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 [email protected]. >> >> To view this discussion visit >> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAOMQ%2Bw_L%2BDZoLM8ApVQQarUWAoVsQ9tueQHjoxeGgYsz8pmSDA%40mail.gmail.com >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAOMQ%2Bw_L%2BDZoLM8ApVQQarUWAoVsQ9tueQHjoxeGgYsz8pmSDA%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> >> -- > 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 [email protected]. > To view this discussion visit > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/5a524e62-a95a-4f37-bd1d-cde385732d9an%40chromium.org > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/5a524e62-a95a-4f37-bd1d-cde385732d9an%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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