On Mon, 27 Apr 2026 at 23:47, 'Stephen Schmith' via blink-dev < [email protected]> wrote:
> Mukundan, the only rollout plan I've found so far is here: > https://developer.chrome.com/docs/web-platform/deprecating-unload#deprecation_timeline > > Unfortunately, as an enterprise developer, this timeline doesn't give me > much information about when I can expect to see impacts from the > deprecation. We've done some work ahead of time to prepare for the > deprecation, but it's simply not clear to me when support for the opt-out > options themselves will also be dropped. I plan to keep those options > enabled for as long as possible because the consequences of this > deprecation could be severe for our customers (I work in compliance, so > think canceled flights, delayed medical research, etc). We don't control > all of the impacted code, so we won't know whether our event wrapper > solutions work for everyone until the deprecation hits production. > There is currently no plan to disable the opt-out options. I'll make sure the link above says this explicitly, F > > On Thursday, April 9, 2026 at 4:11:22 PM UTC-4 Mukundan Kumar wrote: > >> Hi, >> >> Is this event deprecated for all websites or only top 50 websites. Is >> there any detailed roll out plan for this? >> >> On Sunday, May 7, 2023 at 10:43:07 PM UTC-7 Fergal Daly wrote: >> >>> Contact emails >>> >>> [email protected], [email protected] >>> >>> Explainer >>> >>> >>> https://github.com/fergald/docs/blob/master/explainers/permissions-policy-deprecate-unload.md >>> >>> Specification >>> >>> https://github.com/whatwg/html/pull/7915 >>> >>> Summary >>> >>> A Permission-Policy for creating unload event listeners will be added. >>> >>> Initially, the default policy will be set to allow. From there, Chrome >>> will gradually migrate the default policy to deny (i.e. increasingly >>> disallow the creation of unload event listeners, eventually reaching a >>> state where deny fully becomes the default policy). The ultimate goal >>> is to remove support for unload event. >>> >>> Blink component >>> >>> Blink>PermissionsAPI >>> <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink%3EPermissionsAPI> >>> >>> Motivation >>> >>> The unload event is extremely unreliable. It is ignored in most cases by >>> all mobile browsers except Firefox on Android. Furthermore, in Safari, the >>> unload event is ignored on both desktop & mobile platforms. >>> >>> In the current state, unload is a major BFCache blocker (~18 percentage >>> points reduction of hit rate for Chrome). >>> >>> The change will unlock a large fraction of that hit-rate while >>> providing an opt-out for those who need more time to migrate. It also sends >>> a clear signal that unload should not be used in new development. >>> >>> Sidenote: the spec was changed to say that unload should only run if the >>> page cannot enter BFCache, which reflects Safari’s behavior, However >>> neither Chrome nor Mozilla have implemented this behavior. In Chrome's >>> case, we believe that this would suddenly break various sites and would >>> make it hard for developers to know if/when unload may run. >>> >>> >>> Initial public proposal >>> >>> None >>> >>> TAG review >>> >>> https://github.com/w3ctag/design-reviews/issues/738 >>> >>> TAG review status >>> >>> Pending >>> >>> Risks >>> >>> Interoperability and Compatibility >>> >>> If no other browsers implement this, there is a risk that devs continue >>> to use unload widely and pages malfunction on chrome. However given that >>> alternatives to unload exist it seems entirely possible for sites that are >>> actively maintained to move off unload. >>> >>> Gecko: ( >>> https://github.com/mozilla/standards-positions/issues/691#issuecomment-1484997320) >>> It's possible that pages are depending on `unload` handlers in subframes >>> for functionality even without any main frame navigation. We should try to >>> understand how common this is before breaking it. It should be possible to >>> measure how often subframe unloads fire when the mainframe is not >>> navigating. This will give us an upper bound on the size of the problem, - >>> Chrome: we have landed code to measure the occurrence of unload in >>> different scenarios. We will report back the findings. >>> >>> WebKit: https://github.com/WebKit/standards-positions/issues/127 >>> >>> Web developers: Positive ( >>> https://groups.google.com/a/chromium.org/g/bfcache-dev/c/zTIMx7u4uxo/m/-M4IS6LDBgAJ) >>> The web communities we reached out had positive reactions to our proposal >>> and we have not heard about any concrete blockers. >>> >>> 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? >>> >>> On WebView, we will introduce the Permissions-Policy but not move the >>> default to "deny". BFCache does not work on WebView, so the benefit is >>> lower. Meanwhile the risk seems higher as we have far less visibility into >>> the HTML being run in WebViews. A roll-out to WebView should be done >>> independently and in consultation with the WebView team. >>> >>> >>> Debuggability >>> >>> None >>> >>> Is this feature fully tested by web-platform-tests >>> <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md> >>> ? >>> >>> Yes >>> >>> Flag name >>> >>> None >>> >>> Requires code in //chrome? >>> >>> False >>> >>> Estimated milestones >>> >>> M115 for availability of Permissions-Policy >>> >>> M115 is the earliest we would start to disable unload, however >>> >>> Link to entry on the Chrome Platform Status >>> >>> https://chromestatus.com/feature/5579556305502208 >>> >>> -- > You received this message because you are subscribed to a topic in the > Google Groups "blink-dev" group. > To unsubscribe from this topic, visit > https://groups.google.com/a/chromium.org/d/topic/blink-dev/dvusqw9-IhI/unsubscribe > . > To unsubscribe from this group and all its topics, send an email to > [email protected]. > To view this discussion visit > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/6e784026-a0ac-414a-b01c-d6eeddca5a06n%40chromium.org > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/6e784026-a0ac-414a-b01c-d6eeddca5a06n%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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