LGTM3 On Wed, Mar 4, 2026 at 8:29 AM Daniel Bratell <[email protected]> wrote:
> LGTM2 > > /Daniel > On 2026-03-04 17:26, Vladimir Levin wrote: > > Thanks for the responses, > > LGTM1 > > Thanks, > Vlad > > On Wed, Mar 4, 2026 at 11:21 AM 'Gaston Rodriguez' via blink-dev < > [email protected]> wrote: > >> Hi Vlad, >> *> Can you elaborate on the exact change this feature is introducing? It >> sounds like there is no change on Android since all of the required events >> are firing. Which additional events are now fired on other platforms when >> drag starts (and which events were already firing)? * >> *> Are there any events that we are now _not_ firing as a result of this?* >> >> You're right that there's no change in Android since it was already >> satisfying the requirements. I removed the Android 147 ship tag. With this >> change, we now fire three additional events to the drag source on drag >> start: `pointercancel`, `pointerout` and `pointerleave`, there are no >> events that have been removed. I updated the summary by adding the >> following paragraph: >> *> Practically, this means that after a drag has started the drag source >> will now receive the `pointercancel`, `pointerout` and `pointerleave` >> events to indicate that the current event stream has finished.* >> >> *> It seems to be passing right now, is that expected?* >> >> Yes, I had added the flag as experimental and assumed that the WPT >> platform wouldn't run with that flag enabled, TIL. Removed the disclaimer. >> >> Thanks! >> >> On Thursday, February 26, 2026 at 11:21:24 AM UTC-8 Vladimir Levin wrote: >> >>> Hi, >>> >>> Some comments below: >>> >>> On Wed, Feb 25, 2026 at 2:49 PM Chromestatus < >>> [email protected]> wrote: >>> >>>> *Contact emails* >>>> [email protected] >>>> >>>> *Specification* >>>> >>>> https://html.spec.whatwg.org/multipage/dnd.html#drag-and-drop-processing-model:~:text=Fire%20a%20pointer%20event%20at%20the%20source%20node%20named%20pointercancel%2C%20and%20fire%20any%20other%20follow%2Dup%20events%20as%20required%20by%20Pointer%20Events.%20%5BPOINTEREVENTS%5D >>>> >>>> *Summary* >>>> According to the HTML spec, when a drag starts the user agent should >>>> send the appropriate events to the drag source to indicate that the pointer >>>> event stream has ended, and that it shouldn't expect any more events from >>>> this pointer [1]. This code had been partially implemented for mouse events >>>> and fully implemented for touch drags on Android. With the work in this >>>> feature, we aim to fully satisfy this spec requirement on all other >>>> platforms. [1] Pointer event spec definition of pointer stream suppression: >>>> https://w3c.github.io/pointerevents/#suppressing-a-pointer-event-stream >>>> >>>> *Blink component* >>>> Blink>DataTransfer >>>> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EDataTransfer%22> >>>> >>>> *Web Feature ID* >>>> draganddrop <https://webstatus.dev/features/draganddrop> >>>> >>>> *Motivation* >>>> Chromium is currently out of spec when starting drag-and-drop >>>> operations. According to the specification, the user agent must notify the >>>> drag source that it will no longer receive pointer events from the same >>>> input source by firing the corresponding drag-* events. This behavior is >>>> fully implemented only on Android; on other platforms, Chromium does not >>>> fire all of the required events. >>> >>> >>> Can you elaborate on the exact change this feature is introducing? It >>> sounds like there is no change on Android since all of the required events >>> are firing. Which additional events are now fired on other platforms when >>> drag starts (and which events were already firing)? >>> >>> Are there any events that we are now _not_ firing as a result of this? >>> >>> >>>> >>>> *Initial public proposal* >>>> *No information provided* >>>> >>>> *TAG review* >>>> *No information provided* >>>> >>>> *TAG review status* >>>> Not applicable >>>> >>>> *Risks* >>>> >>>> >>>> *Interoperability and Compatibility* >>>> Other browsers also fall out of spec in this particular point and don't >>>> send the appropriate events when a drag starts, which means that Chromium >>>> will be the only browser that implements this behavior. >>>> >>>> *Gecko*: Neutral (https://bugzilla.mozilla.org/show_bug.cgi?id=1994552) A >>>> bug has been filed and has received interest from Firefox developers. >>>> >>>> *WebKit*: No signal ( >>>> https://github.com/WebKit/standards-positions/issues/598) (Will update >>>> the signal when the issue receives feedback) >>>> >>>> *Web developers*: Positive ( >>>> https://github.com/w3c/pointerevents/issues/555) We have received >>>> developer feedback [1] regarding the browser's behavior with respect to the >>>> specification. >>>> >>>> *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, and if any issue is found, we have a feature flag acting as a kill >>>> switch (SuppressPointerStreamAfterDrag). >>>> >>>> >>>> *Debuggability* >>>> No additional functionality is needed to be added to debug this feature >>>> >>>> *Will this feature be supported on all six Blink platforms (Windows, >>>> Mac, Linux, ChromeOS, Android, and Android WebView)?* >>>> Yes >>>> >>>> *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/html/editing/dnd/events/pointer-suppression.html >>>> (currently failing because the change is behind a disabled feature flag) >>>> >>> >>> It seems to be passing right now, is that expected? >>> >>> Thanks! >>> Vlad >>> >>> >>>> >>>> *Flag name on about://flags* >>>> *No information provided* >>>> >>>> *Finch feature name* >>>> SuppressPointerStreamAfterDrag >>>> >>>> *Non-finch justification* >>>> The feature will be shipped enabled by default to be used as a >>>> kill-switch in case a severe issue is discovered. >>>> >>>> *Rollout plan* >>>> Will ship enabled for all users >>>> >>>> *Requires code in //chrome?* >>>> False >>>> >>>> *Tracking bug* >>>> https://issues.chromium.org/issues/452372355 >>>> >>>> *Estimated milestones* >>>> Shipping on desktop 147 >>>> Shipping on Android 147 >>>> >>>> *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). >>>> N/A >>>> >>>> *Link to entry on the Chrome Platform Status* >>>> https://chromestatus.com/feature/6732314958757888?gate=6606447989358592 >>>> >>>> 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/699f5247.050a0220.1eaaa1.0000.GAE%40google.com >>>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/699f5247.050a0220.1eaaa1.0000.GAE%40google.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/523eb706-f81c-4713-835e-1a95361af6d5n%40chromium.org >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/523eb706-f81c-4713-835e-1a95361af6d5n%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/CADsXd2Poogbi%2Bj%2BQY7kfh2xL05CiJ2VCUGVWLD4Xtu%3D%2B8WYudQ%40mail.gmail.com > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CADsXd2Poogbi%2Bj%2BQY7kfh2xL05CiJ2VCUGVWLD4Xtu%3D%2B8WYudQ%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/978a4078-3c26-4b53-b01a-3d751fc1658c%40gmail.com > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/978a4078-3c26-4b53-b01a-3d751fc1658c%40gmail.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/CAOMQ%2Bw86fqoFKm5gqowM-GkBSTqPPuEU2xtETZ6ekLejUpaMZw%40mail.gmail.com.
