Thanks for the update, and apologies for not being clearer. I meant that it'd be good to update the WebKit position thread, as WebKit folks ended it with "An A/B experiment could be interesting for sure as well as more information as to which websites would want to adopt this (but would not want to work offline)."
If we can provide them with data that can help sway them, we should :) On Tue, Mar 31, 2026 at 12:47 PM Yoshisato Yanagisawa < [email protected]> wrote: > Let me share the summary of origin trials as Yoav asked: > > Currently, 35 sites, including large and medium-scale origins, > participated in the origin trials. Usage metrics can be found at > https://chromestatus.com/metrics/feature/timeline/popularity/5550. > > Developers expressed strong interest in using this feature to maintain a > SharedWorker's lifetime across same-origin navigations within a single tab. > While there were requests for seamless migration from non-extended to > extended lifetime workers, we identified a potential "footgun" regarding > WebLocks where a long-lived worker could hold a lock indefinitely. To > ensure safety, we decided to enforce strict separation between the two > lifetime modes. > > Feedback also showed that the feature effectively handles asynchronous > tasks after a page unloads in most scenarios. However, some sites with > strict Content Security Policies (CSP) encountered issues when using the > feature with blob: URLs. > > Notably, extended lifetime shared workers were successfully integrated > into the HTML standard during the OT period, with positive signals from > other browser vendors. Additionally, as we are working on enabling > SharedWorker on Android (as discussed in a separate thread), this feature > will also be available on Android following that rollout. To improve > observability, chrome://inspect/#workers was updated to indicate whether a > SharedWorker is running with the extendedLifetime flag. > > Please let me know if you have any questions. > > 2026年3月31日(火) 18:22 Yoav Weiss (@Shopify) <[email protected]>: > >> LGTM1 >> >> On Tue, Mar 31, 2026 at 8:09 AM Chromestatus < >> [email protected]> wrote: >> >>> *Contact emails* >>> [email protected], [email protected] >>> >>> *Explainer* >>> >>> https://gist.github.com/domenic/c5bd38339f33b49120ae11b3b4af5b9b#file-1-explainer-md >>> >>> *Specification* >>> >>> https://github.com/whatwg/html/commit/9c009049e4fa9dba638ef68ca502b781082bbb68 >> >> >> https://github.com/whatwg/html/pull/11600 is a slightly more convenient >> link. >> >> >>> >>> >>> *Summary* >>> This update adds a new option, `extendedLifetime: true`, to the >>> `SharedWorker` constructor. This requests that the shared worker be kept >>> alive even after all current clients have unloaded. The primary use case is >>> to allow pages to perform asynchronous work that requires JavaScript after >>> a page unloads, without needing to rely on a service worker. >>> >>> *Blink component* >>> Blink>Workers >>> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EWorkers%22> >>> >>> *Web Feature ID* >>> shared-workers <https://webstatus.dev/features/shared-workers> >>> >>> *Motivation* >>> Many sites want to perform some work during document unloading. This >>> usually includes writing to storage, or sending information to severs. >>> Currently, if this work is done asynchronously (e.g., writing to IndexedDB >>> instead of localStorage, or using CompressionStream to compress the body >>> before sending a fetch()) the only way to do this is to use a service >>> worker. However, requiring a service worker for this simple case of >>> work-after-unload is heavyweight: the disk space, memory consumption, and >>> developer experience of managing the service worker registration and >>> lifecycle makes this hard to deploy. By using shared workers, all of these >>> downsides are avoided. >>> >>> *Initial public proposal* >>> https://github.com/whatwg/html/issues/10997 >>> >>> *TAG review* >>> https://github.com/w3ctag/design-reviews/issues/1089 >>> >>> *TAG review status* >>> Pending >>> >>> *Origin Trial Name* >>> Extended lifetime shared workers >>> >>> *Goals for experimentation* >>> None >>> >>> *Chromium Trial Name* >>> SharedWorkerExtendedLifetime >>> >>> *Origin Trial documentation link* >>> >>> https://gist.github.com/domenic/c5bd38339f33b49120ae11b3b4af5b9b#file-1-explainer-md >>> >>> *WebFeature UseCounter name* >>> kSharedWorkerExtendedLifetimeFeatureEnabled >>> >>> *Risks* >>> >>> >>> *Interoperability and Compatibility* >>> We intend to specify that the lifetime timeout for these shared workers >>> be extended in the same way as service workers. Because the exact timeout >>> of service workers is left implementation-defined, it's possible that code >>> using this new feature could be non-interoperable. However, this has so far >>> not proved to be a major problem in practice for service workers. >>> >>> *Gecko*: Positive ( >>> https://github.com/mozilla/standards-positions/issues/1227) Some >>> unofficial tentative positive signals and engagement in the proposal issue. >>> >>> *WebKit*: No signal ( >>> https://github.com/WebKit/standards-positions/issues/492) Some >>> unofficial tentative negative signals in the proposal issue. >>> >> >> It'd be good to update that thread with OT results, as discussed. >> >> >>> >>> *Web developers*: Positive The problem of wanting to perform >>> asynchronous work during unload is well-known, with the service worker >>> workaround currently deployed, including by Google properties. >>> >>> *Other signals*: >>> >>> *WebView application risks* >>> >>> Does this intent deprecate or change behavior of existing APIs, such >>> that it has potentially high risk for Android WebView-based applications? >>> *No information provided* >>> >>> >>> *Debuggability* >>> The chrome://inspect/#workers page indicates when a SharedWorker is >>> using the extendedLifetime option. >>> >>> *Will this feature be supported on all six Blink platforms (Windows, >>> Mac, Linux, ChromeOS, Android, and Android WebView)?* >>> No >>> Shared workers are not yet supported on Android and Android WebView. >>> However, we are concurrently working on enabling them there, and when we >>> do, this feature will also be supported. >>> >>> *Is this feature fully tested by web-platform-tests >>> <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md>?* >>> Yes >>> >>> https://wpt.fyi/results/workers/tentative/SharedWorker-extendedLifetime.html >>> >>> *Flag name on about://flags* >>> *No information provided* >>> >>> *Finch feature name* >>> SharedWorkerExtendedLifetime >>> >>> *Rollout plan* >>> Will ship enabled for all users >>> >>> *Requires code in //chrome?* >>> False >>> >>> *Tracking bug* >>> https://issues.chromium.org/issues/400473072 >>> >>> *Estimated milestones* >>> Shipping on desktop 148 >>> Origin trial desktop first 139 >>> Origin trial desktop last 142 >>> Origin trial extension 1 end milestone 145 >>> Origin trial extension 2 end milestone 148 >>> Shipping on Android 148 >>> Shipping on WebView 148 >>> >>> *Anticipated spec changes* >>> >>> Open questions about a feature may be a source of future web compat or >>> interop issues. Please list open issues (e.g. links to known github issues >>> in the project for the feature specification) whose resolution may >>> introduce web compat/interop risk (e.g., changing to naming or structure of >>> the API in a non-backward-compatible way). >>> We are currently discussing some details in preparation for >>> specification. The exact nature of how the lifetime extension works with >>> regard to non-window clients, particularly, has only recently reached a >>> tentative conclusion. >>> >>> *Link to entry on the Chrome Platform Status* >>> https://chromestatus.com/feature/5138641357373440?gate=4686145547665408 >>> >>> *Links to previous Intent discussions* >>> Intent to Experiment: >>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/6862683f.170a0220.16d1bf.0122.GAE%40google.com >>> Intent to Extend Experiment 1: >>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/68de2b1f.050a0220.58465.05c2.GAE%40google.com >>> Intent to Extend Experiment 2: >>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/69704662.2b0a0220.2c228a.0283.GAE%40google.com >>> >>> >>> This intent message was generated by Chrome Platform Status >>> <https://chromestatus.com>. >>> >>> -- >>> 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/69cb650f.050a0220.201b21.039e.GAE%40google.com >>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/69cb650f.050a0220.201b21.039e.GAE%40google.com?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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