My i2s message missed one important point: we are planning for an incremental rollout on Stable, just to be on the safe side from the compat perspective (see my WIP finch config cl/721367851, sorry internal link).
> To move everyone toward interop, I suggest commenting on https://bugzilla.mozilla.org/show_bug.cgi?id=1885232 to encourage Firefox to fast-follow, and maybe filing a WebKit bug for the same reason. @Domenic Denicola <dome...@chromium.org> Perhaps we can defer this until after a 100% Stable rollout, right? On Wed, Feb 5, 2025 at 9:29 PM Domenic Denicola <dome...@chromium.org> wrote: > LGTM1. This seems like a valuable movement toward interop on tricky > edge-cases, and the team has done a good job with use counters and beta > experiments to bound the compat risks. I think Finch can be used as a > killswitch if we find that this has some horrible breaking impact that has > not yet been discovered. > > One path toward gaining even more confidence here would be to investigate > individual sites. You could use either UKM or HTTP archive analysis to find > sites where the upper-bound use counter fires, and then manually try to > play around with them both with and without the flag to see if anything is > broken. > > To move everyone toward interop, I suggest commenting on > https://bugzilla.mozilla.org/show_bug.cgi?id=1885232 to encourage Firefox > to fast-follow, and maybe filing a WebKit bug for the same reason. > > > On Thu, Feb 6, 2025 at 6:22 AM Mustaq Ahmed <mus...@chromium.org> wrote: > >> Hi Mike and Yoav: >> >> Let me answer your questions together: >> >> *Current behavior in major browsers:* The click target is: >> - [Chrome] the common ancestor of pointerdown target and *captured* >> pointerup target. >> - [Firefox] the actual pointerup target, ignoring capture and pointerdown. >> - [Safari] the common ancestor of pointerdown target and actual pointerup >> target, ignoring capture. >> >> *Compat risk analysis:* >> - Our UseCounter shows that ~0.1% of Chrome page loads have (a) click >> handlers at both the common ancestor and the capture target, and (b) this >> feature would switch the click target from the former to the latter. This >> seems like a loose upper bound because the two handlers could be doing the >> same job. >> https://chromestatus.com/metrics/feature/timeline/popularity/3942 >> - We have the feature enabled on Canary & Dev for 7 weeks and on Beta for >> 3 weeks, and we didn't see any bug reports. >> >> *Developers possibly capturing to a "wrong" element:* >> IMHO it is hard to be "wrong" here, let me explain why. Developers use >> capturing mostly for a custom drag experience, like the slider mentioned in >> the intent or a map widget, and "click" is not an expected UI action after >> such a drag. It seems impossible to know how often developers expect >> clicks here, if at all. If any developers do expect clicks, they have to >> resort to a hack (like adding one listener to multiple targets) because the >> click-target inconsistencies among major browsers today left no "right" way >> to capture a click! Did it answer your question @Yoav Weiss >> <yoavwe...@chromium.org>? >> >> >> >> On Wed, Feb 5, 2025 at 11:32 AM Yoav Weiss (@Shopify) < >> yoavwe...@chromium.org> wrote: >> >>> >>> >>> On Wed, Feb 5, 2025 at 4:11 PM Mustaq Ahmed <mus...@chromium.org> wrote: >>> >>>> Contact emailsmus...@chromium.org >>>> >>>> Explainerhttps://w3c.github.io/pointerevents/#event-dispatch >>>> >>>> Specificationhttps://w3c.github.io/pointerevents/#event-dispatch >>>> >>>> Summary >>>> >>>> If a pointer is captured while the `pointerup` event is being >>>> dispatched, the `click` event will be dispatched to the captured target >>>> instead of the nearest common ancestor of `pointerdown` and `pointerup` >>>> events as per the UI Event spec. For uncaptured pointers, the `click` >>>> target remains unchanged. >>>> >>>> >>>> Blink componentBlink>Input >>>> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EInput%22> >>>> >>>> TAG reviewNone >>>> >>>> TAG review statusNot applicable >>>> >>>> Risks >>>> >>>> >>>> Interoperability and Compatibility >>>> >>>> Interop risk: No risk at all because the major browsers behaved >>>> differently for years (see >>>> https://github.com/w3c/pointerevents/issues/356#issuecomment-811814819). >>>> Compat risk: There is a slight risk that the click target change would be >>>> noticed for a very narrow case of a slider-like UI element that captures >>>> the pointer yet expects a *container* element to respond to a click >>>> differently from how the slider element itself responds to the same click. >>>> For a drag action that starts on the slider and ends outside the slider, >>>> this feature would cause the click event to be dispatched to the slider >>>> then bubble up to the container (vs being dispatched to the container >>>> element directly). >>>> >>> >>> Have we tried to quantify the compat risk here? >>> How often do we expect developers to capture the "wrong" element from >>> their perspective? >>> >>> >>>> >>>> >>>> *Gecko*: Positive ( >>>> https://github.com/w3c/pointerevents/issues/356#issuecomment-1596196064 >>>> ) >>>> >>>> *WebKit*: No signal >>>> >>>> *Web developers*: Positive ( >>>> https://github.com/w3c/pointerevents/issues/356#issuecomment-1591894867 >>>> ) >>>> >>>> *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? >>>> >>>> None >>>> >>>> >>>> Debuggability >>>> >>>> None >>>> >>>> >>>> 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/pointerevents?label=master&label=experimental&aligned&q=pointerevents%2Fpointerevent_click_during_capture.html >>>> >>>> >>>> Flag name on about://flagsNone >>>> >>>> Finch feature nameClickToCapturedPointer >>>> >>>> Requires code in //chrome?False >>>> >>>> Tracking bughttps://crbug.com/40851596 >>>> >>>> Sample links >>>> https://codepen.io/mustaqahmed/full/YzawKWW >>>> >>>> Estimated milestones >>>> Shipping on desktop 135 >>>> Shipping on Android 135 >>>> Shipping on WebView 135 >>>> >>>> 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). >>>> None >>>> >>>> Link to entry on the Chrome Platform Status >>>> https://chromestatus.com/feature/5143357002874880?gate=5069716701577216 >>>> >>>> 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 blink-dev+unsubscr...@chromium.org. >>>> To view this discussion visit >>>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAB0cuO5WP0%3DEV2%3DiQkS2Bkt8z4fKnfMFNBNeBEU76xOSsYNCHA%40mail.gmail.com >>>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAB0cuO5WP0%3DEV2%3DiQkS2Bkt8z4fKnfMFNBNeBEU76xOSsYNCHA%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 blink-dev+unsubscr...@chromium.org. >> To view this discussion visit >> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAB0cuO4kZU5RxQiMGhMZqkDdPqGsdZLUd11bFY5xbyoizvFkhQ%40mail.gmail.com >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAB0cuO4kZU5RxQiMGhMZqkDdPqGsdZLUd11bFY5xbyoizvFkhQ%40mail.gmail.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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