Hi API Owners: We concluded this feature is safe to ship after investigating the few sites that are affecting our use-counter: - None of UKM reported sites show any usability problem in our investigation. - On one of those sites, a mouse drag over menu items starts text selection (w/o affecting usability). The site shows the same problem with Firefox and Safari; and even on Chrome Stable (w/o the feature) but for certain menu-item drags. - The UKM usage percentages for those sites add up to match the ~0.12% usage shown by our use-counter. So no sites affecting our use-counter seem to have been left out by UKM.
In case this is still needed, we are rolling out the 1% Stable experiment that we promised on Jan 17. Mustaq On Wed, Mar 6, 2024 at 10:06 AM Mustaq Ahmed <[email protected]> wrote: > No, issue 327409885 is related to the PSA on canceling mousedown in iframe > <https://groups.google.com/a/chromium.org/g/blink-dev/c/RYzJrvPzHss/m/QsopwzYQAAAJ> > . > > > On Wed, Mar 6, 2024 at 5:25 AM Yoav Weiss (@Shopify) < > [email protected]> wrote: > >> Is https://issues.chromium.org/issues/327409885 related here? >> >> On Mon, Mar 4, 2024 at 6:09 PM Mustaq Ahmed <[email protected]> wrote: >> >>> UKM data shows that only a few popular sites are affecting our >>> use-counters. We already confirmed that one of those sites is not broken >>> at all, only showing text selection on menu items. We are expecting to >>> conclude soon after investigating all those sites. >>> >>> On Wed, Jan 17, 2024 at 1:48 PM Mustaq Ahmed <[email protected]> >>> wrote: >>> >>>> A quick update: our use-counter on Chrome 122 Canary/Dev came out >>>> higher than we expected---it is suggesting that at most 0.11% page loads >>>> are affected. >>>> >>>> We will expand the finch trail to 50% Beta plus 1% Stable now to get >>>> more data, and then look into other directions like adding UKM or fine >>>> tuning the use-counter. >>>> >>>> >>>> On Thu, Dec 7, 2023 at 10:14 AM Rick Byers <[email protected]> wrote: >>>> >>>>> >>>>> >>>>> On Wed, Dec 6, 2023 at 5:08 PM Mustaq Ahmed <[email protected]> >>>>> wrote: >>>>> >>>>>> > I assume cancelling the mousedown (but not the mousemove) still >>>>>> prevents selection and drag-and-drop in all browsers, is that right? >>>>>> That's >>>>>> the pattern I'd expect is most common. Also, what's the behavior of >>>>>> pointermove for mice today and after this change? >>>>>> >>>>>> I just confirmed <https://codepen.io/mustaqahmed/full/wvNYGEP> that >>>>>> Chrome (and Firefox and Safari too) already prevents both selection and >>>>>> drag-and-drop when mousedown or pointerdown is cancelled. So sites >>>>>> canceling all the mouse events will work fine. >>>>>> >>>>> >>>>> Great, thanks! That definitely lowers my concern. >>>>> >>>>> > We have landed a metric which specifically checks for cases where >>>>>> the mousemove is preventDefaulted but a selection starts (i.e. >>>>>> selectstart >>>>>> wasn't prevented, there was no user-select: none, and so the selection >>>>>> does >>>>>> change). Right now this is a UMA but we could also add UKM and get sites >>>>>> from this. Mustaq WDYT about adding UKM for this and running the 1% >>>>>> finch trial? >>>>>> >>>>>> Adding UKM and running a 1% finch trial sounds good. >>>>>> >>>>>> Perhaps we can run a Canary/Dev/Beta trial even now (on M121)? >>>>>> >>>>> >>>>> Yep, you can do whatever you want for canary/dev and you have API >>>>> owner approval for Beta and Stable up to 1% if you want it. Perhaps beta >>>>> data alone would be compelling enough for API owners to approve this (with >>>>> an understanding, like always, that we'd kill-switch it on reports of >>>>> non-trivial stable breakage). >>>>> >>>>> On Wed, Dec 6, 2023 at 12:34 PM Robert Flack <[email protected]> >>>>>> wrote: >>>>>> >>>>>>> On Wed, Dec 6, 2023 at 12:18 PM Rick Byers <[email protected]> >>>>>>> wrote: >>>>>>> >>>>>>>> API owners met and discussed this one briefly today. There was >>>>>>>> agreement that more work needs to be done to demonstrate the compat >>>>>>>> risk is >>>>>>>> low enough to ship this breaking change. A few points: >>>>>>>> >>>>>>>> - If you'd like to do a finch trial to gather data (up to >>>>>>>> stable 1%) we're supportive of that. >>>>>>>> - Mike Taylor argued that you're not likely to learn too much >>>>>>>> useful from a finch trial since people seem not to report bugs for >>>>>>>> things >>>>>>>> that fail for a seemingly random 1% of their users, and perhaps the >>>>>>>> idea of >>>>>>>> surveying a few sites would be more effective at finding real >>>>>>>> breakage. Of >>>>>>>> course UKM + Finch might be a good way to find URLs to test. >>>>>>>> >>>>>>>> We have landed a metric which specifically checks for cases where >>>>>>> the mousemove is preventDefaulted but a selection starts (i.e. >>>>>>> selectstart >>>>>>> wasn't prevented, there was no user-select: none, and so the selection >>>>>>> does >>>>>>> change). Right now this is a UMA but we could also add UKM and get sites >>>>>>> from this. Mustaq WDYT about adding UKM for this and running the 1% >>>>>>> finch >>>>>>> trial? >>>>>>> >>>>>> >>>>> Ah that makes sense. Sorry I only took a quick glance at the code for >>>>> the UseCounter and missed that. That's indeed much more relevant than I >>>>> was >>>>> thinking, maybe it won't be so high after all and that can give us good >>>>> confidence to ship? >>>>> >>>>>> >>>>>>>> - Mike also argued that in his experience, he'd expect sites >>>>>>>> like mapping apps to have engine-specific conditional code around >>>>>>>> their >>>>>>>> event handling, so that increases the risk. >>>>>>>> - Philip and I discussed that if there is evidence of real >>>>>>>> breakage we can't accept, we should propose changing the spec here >>>>>>>> - it >>>>>>>> seems like it would be very reasonable if cancelling the first >>>>>>>> mousemove >>>>>>>> event in a sequence canceled text selection (just like cancelling >>>>>>>> the first >>>>>>>> touchmove prevents scrolling). But if we have reasonable evidence >>>>>>>> that it's >>>>>>>> non-breaking, we're happy to just align with WebKit and Gecko for >>>>>>>> improved >>>>>>>> interoperability. >>>>>>>> >>>>>>>> Agreed, though it may be breaking for other engines to change >>>>>>> behavior too though, right? E.g. we are in a similar situation with >>>>>>> overscroll-behavior on the root element (crbug.com/954423 >>>>>>> <https://bugs.chromium.org/p/chromium/issues/detail?id=954423&q=overscroll-behavior%20root&can=2>) >>>>>>> where changing either behavior to the other will have compat risk. >>>>>>> >>>>>> >>>>> Oh good point. And breaking intended selection is arguably worse than >>>>> allowing unintended selection. Ok, that's a further argument for us >>>>> accepting more risk here, thanks. >>>>> >>>>>> >>>>>>>> - All agreed we're willing to take some risk here to achieve >>>>>>>> interop quickly and don't want to impose too much of a burden of >>>>>>>> proof, >>>>>>>> especially since the severity of breakage is likely low. We just >>>>>>>> need some >>>>>>>> more evidence that the risk is manageable. >>>>>>>> >>>>>>>> Perhaps the most pragmatic path would be something like: >>>>>>>> >>>>>>>> 1. Survey at least 5 sites with mouse drag involving DOM and >>>>>>>> explain why they're unimpacted (cancelling mousedown? cancelling >>>>>>>> selectionstart? or just user-select: none?). If you find one that >>>>>>>> is indeed >>>>>>>> broken, revisit plan. >>>>>>>> 2. Work with the enterprise team on release notes & plan - i.e. >>>>>>>> either finch roll out with commitment to killswitch if we get >>>>>>>> reports of >>>>>>>> enterprise breakage, or add a policy knob opt-out >>>>>>>> 3. Go for 100% but be prepared to killswitch if there are >>>>>>>> non-trivial reports of breakage, then revisit with either a >>>>>>>> migration plan >>>>>>>> (outreach, blog post) or proposed spec change >>>>>>>> >>>>>>>> WDYT? >>>>>>>> >>>>>>> >>>>>>> This sounds reasonable. I think running the 1% experiment with the >>>>>>> targeted metric (cases where selection now happens when it didn't used >>>>>>> to) >>>>>>> should help us gain confidence. >>>>>>> >>>>>>> Rick >>>>>>>> >>>>>>>> On Tue, Dec 5, 2023 at 3:42 PM Rick Byers <[email protected]> >>>>>>>> wrote: >>>>>>>> >>>>>>>>> Hey Mustaq, >>>>>>>>> Thanks for pushing to get this long-time interop issue addressed! >>>>>>>>> I assume cancelling the mousedown (but not the mousemove) still >>>>>>>>> prevents >>>>>>>>> selection and drag-and-drop in all browsers, is that right? That's the >>>>>>>>> pattern I'd expect is most common. Also, what's the behavior of >>>>>>>>> pointermove >>>>>>>>> for mice today and after this change? >>>>>>>>> >>>>>>>>> What's your plan for if the UseCounter comes back high? FWIW, I'm >>>>>>>>> betting that it will. First I expect it'll be common for sites to >>>>>>>>> cancel all the mouse events. If my understanding above is correct, >>>>>>>>> then >>>>>>>>> perhaps you want to exclude those from your UseCounter since the >>>>>>>>> behavior >>>>>>>>> won't change in those cases? But secondly, given past history with >>>>>>>>> some >>>>>>>>> major sites, I suspect there might be a long tail of sites that are >>>>>>>>> lightly >>>>>>>>> broken here. Maybe worth doing a finch-based rollout to mitigate the >>>>>>>>> risk? >>>>>>>>> I'd support going up to stable 1% now to see if we learn of any >>>>>>>>> issues. I'm >>>>>>>>> particularly worried about enterprise (LOB) apps which are often >>>>>>>>> chromium-only. We'll see what Enterprise review says on the launch, >>>>>>>>> but >>>>>>>>> they might want >>>>>>>>> <https://www.chromium.org/developers/enterprise-changes/> a >>>>>>>>> mention in the release notes and a policy opt-out. Then again perhaps >>>>>>>>> since >>>>>>>>> the breakage is likely to be rare and cosmetic, just doing a >>>>>>>>> finch-based >>>>>>>>> roll-out (and hitting a finch killswitch on reports of any issues) >>>>>>>>> should >>>>>>>>> be enough to mitigate the risk. >>>>>>>>> >>>>>>>>> You might also consider enabling UKM support >>>>>>>>> <https://source.chromium.org/chromium/chromium/src/+/main:components/page_load_metrics/browser/observers/use_counter/ukm_features.cc?q=ukm_features&ss=chromium> >>>>>>>>> for >>>>>>>>> your UseCounter to get some sample URLs, though again I'd worry you >>>>>>>>> might >>>>>>>>> get lots of hits but not be able to easily reproduce any obvious >>>>>>>>> breakage. >>>>>>>>> Alternately it might be most useful to just spot check 5-10 major >>>>>>>>> sites >>>>>>>>> which have mouse dragging behavior with DOM (not just canvas) and >>>>>>>>> catalog >>>>>>>>> how they avoid getting unintended selection (eg. do they cancel >>>>>>>>> selectstart >>>>>>>>> or use user-select: none). I think mapping sites are an obvious >>>>>>>>> example, >>>>>>>>> gmail has some message dragging behavior I think, not sure what else. >>>>>>>>> >>>>>>>>> Rick >>>>>>>>> >>>>>>>>> On Mon, Dec 4, 2023 at 2:35 PM Mustaq Ahmed <[email protected]> >>>>>>>>> wrote: >>>>>>>>> >>>>>>>>>> Contact [email protected], [email protected] >>>>>>>>>> >>>>>>>>>> ExplainerNone >>>>>>>>>> >>>>>>>>>> Specificationhttps://w3c.github.io/uievents/#event-type-mousemove >>>>>>>>>> >>>>>>>>>> Summary >>>>>>>>>> >>>>>>>>>> Canceling mousemove will not prevent text selection or >>>>>>>>>> drag-and-drop. Chrome allowed cancelling mousemove events to prevent >>>>>>>>>> other >>>>>>>>>> APIs like text selection (and even drag-and-drop in the past). This >>>>>>>>>> does >>>>>>>>>> not match other major browsers; nor does it conform to the UI Event >>>>>>>>>> spec: >>>>>>>>>> https://w3c.github.io/uievents/#event-type-mousemove Through >>>>>>>>>> this feature, the default-action of mousemove becomes none. Text >>>>>>>>>> selection >>>>>>>>>> and drag-and-drop can still be prevented through cancelling >>>>>>>>>> selectstart and >>>>>>>>>> dragstart events respectively, which are spec compliant and fully >>>>>>>>>> interoperable. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> Blink componentBlink>Input >>>>>>>>>> <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink%3EInput> >>>>>>>>>> >>>>>>>>>> TAG reviewNone >>>>>>>>>> >>>>>>>>>> TAG review statusNot applicable >>>>>>>>>> >>>>>>>>>> Risks >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> Interoperability and Compatibility >>>>>>>>>> >>>>>>>>>> This feature will make Chrome fully interoperable. Chrome is >>>>>>>>>> currently failing the corresponding WPT (a part of Interop 2023) >>>>>>>>>> while both >>>>>>>>>> Mozilla and WebKit have started passing the WPT recently. There is a >>>>>>>>>> bit of >>>>>>>>>> compat risk. We attempted it twice in the past but had to revert for >>>>>>>>>> two >>>>>>>>>> different reasons: in 2014 we faced a text-selection regression >>>>>>>>>> https://crbug.com/485892 on an app that no longer shows the >>>>>>>>>> problem (because app event handling changed), then in 2018 we faced a >>>>>>>>>> drag-and-drop regression https://crbug.com/878392 that is >>>>>>>>>> irrelevant now (because Chrome drag-and-drop changed). For our >>>>>>>>>> current >>>>>>>>>> attempt the risk from text-selection remains, and we need to expose >>>>>>>>>> the >>>>>>>>>> feature to be able to assess the risk. We have added a use-counter >>>>>>>>>> and >>>>>>>>>> turned on the feature as "experimental" on M121 to observe field data >>>>>>>>>> before shipping it. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> *Gecko*: Shipped/Shipping ( >>>>>>>>>> https://bugzilla.mozilla.org/show_bug.cgi?id=1823663) >>>>>>>>>> >>>>>>>>>> *WebKit*: Shipped/Shipping ( >>>>>>>>>> https://bugs.webkit.org/show_bug.cgi?id=262878) >>>>>>>>>> >>>>>>>>>> *Web developers*: Positive (https://crbug.com/346473#c6) >>>>>>>>>> >>>>>>>>>> *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)?No >>>>>>>>>> >>>>>>>>>> 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/uievents/mouse/mousemove_prevent_default_action.tentative.html?label=experimental&label=master&aligned >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> Flag name on chrome://flagsNone >>>>>>>>>> >>>>>>>>>> Finch feature nameMouseDragOnCancelledMouseMove >>>>>>>>>> >>>>>>>>>> Requires code in //chrome?False >>>>>>>>>> >>>>>>>>>> Tracking bughttps://crbug.com/346473 >>>>>>>>>> >>>>>>>>>> MeasurementWe have added the use-counter >>>>>>>>>> kMouseDragOnCancelledMouseMove to track possible regressions in the >>>>>>>>>> wild. >>>>>>>>>> >>>>>>>>>> Sample links >>>>>>>>>> https://codepen.io/mustaqahmed/full/wvNYGEP >>>>>>>>>> >>>>>>>>>> Estimated milestones >>>>>>>>>> Shipping on desktop 122 >>>>>>>>>> Shipping on Android 122 >>>>>>>>>> Shipping on WebView 122 >>>>>>>>>> >>>>>>>>>> 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/5145305056280576 >>>>>>>>>> >>>>>>>>>> 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 on the web visit >>>>>>>>>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAB0cuO7reN%2B6Wb_N99jNm_aJY7fhhQ1ncCrh_J_%2BFCLdASm0eg%40mail.gmail.com >>>>>>>>>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAB0cuO7reN%2B6Wb_N99jNm_aJY7fhhQ1ncCrh_J_%2BFCLdASm0eg%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 on the web visit >>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAB0cuO4KQ%3DcN7O6eE70AWuw-y-Q7LtR_TiZTYrvz8giVfdQrNA%40mail.gmail.com >>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAB0cuO4KQ%3DcN7O6eE70AWuw-y-Q7LtR_TiZTYrvz8giVfdQrNA%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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