LGTM3 On Wednesday, October 29, 2025 at 11:10:37 AM UTC-4 Alex Russell wrote:
> LGTM2 > > On Wednesday, October 29, 2025 at 4:10:14 PM UTC+1 Chris Harrelson wrote: > >> LGTM1 >> >> On Wed, Oct 29, 2025 at 7:44 AM 'Michal Mocny' via blink-dev < >> [email protected]> wrote: >> >>> (I have updated the target milestone to 144) >>> >>> On Wed, Oct 22, 2025 at 5:41 PM Chromestatus < >>> [email protected]> wrote: >>> >>>> *Contact emails* >>>> [email protected] >>>> >>>> *Specification* >>>> https://www.w3.org/TR/event-timing/#dom-performance-interactioncount >>>> >>>> *Design docs* >>>> *No information provided* >>>> https://www.w3.org/TR/event-timing/#dom-performance-interactioncount >>>> https://www.w3.org/TR/event-timing/#sec-increasing-interaction-count >>>> >>>> *Summary* >>>> The Event Timing API is part of the Performance Timeline and is used to >>>> measure the performance of user interactions. Certain Events will have an >>>> interactionId value assigned to them, and this is useful for grouping >>>> related interactions based on common physical user inputs or gestures. >>>> This >>>> feature adds a very trivial performance.interactionCount, which is just >>>> the >>>> total number of interactions that have occured on the page. In particular, >>>> this feature is useful for computing the Interaction to Next Paint (INP) >>>> metric value, which requires knowing the total number of interactions in >>>> order to compute a high percentile score (p98 for pages with greater than >>>> 50 total interactions). This feature has been specced for a long while, >>>> was >>>> prototypes in Chromium a long time ago but never shipped, is part of >>>> Interop 2025, and is already available in other browsers. (Note: there is >>>> already a more powerful performance.eventCounts map for specific events, >>>> but it is not possible to accurately map event cunts to interaction >>>> counts.) >>>> >>>> *Blink component* >>>> Blink>PerformanceAPIs >>>> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EPerformanceAPIs%22> >>>> >>>> *Web Feature ID* >>>> event-timing <https://webstatus.dev/features/event-timing> >>>> >>>> *Motivation* >>>> Used to count the number of important real user interactions with a >>>> page. This is distinct from counting the number of events that Event >>>> Timing >>>> measures (because a single physical user gesture may fire many, variable >>>> number, of specific events, depending on the type of input and event >>>> target >>>> and page design) but you can already count interactions (inconveniently) >>>> by >>>> just counting the number of unique interactionId values in Event Timing >>>> API. Used for calculating Interaction to Next Paint (INP) metric. >>>> >>>> *Initial public proposal* >>>> *No information provided* >>>> >>>> *TAG review* >>>> *No information provided* >>>> >>>> *TAG review status* >>>> Not applicable >>>> >>>> *Risks* >>>> >>>> >>>> *Interoperability and Compatibility* >>>> Other browser venders have already shipped this feature as part of the >>>> Interop 2025 effort for CWV INP. The main interop risk is that there are >>>> existing polyfills for interactionCount in Chromium for INP calculation. >>>> However, popular polyfills (such as web-vitals.js) have long been tested >>>> to >>>> feature detect, given the long experimental web platform implementation in >>>> chromium. >>>> >>>> *Gecko*: Shipped/Shipping ( >>>> https://groups.google.com/a/mozilla.org/g/dev-platform/c/xvv6sxJZc4U/m/JzSSCoxPAgAJ?e=48417069 >>>> ) >>>> >>>> *WebKit*: In development ( >>>> https://bugs.webkit.org/show_bug.cgi?id=297361) >>>> >>>> *Web developers*: Strongly positive No specific link, but this feature >>>> is related to the very popular INP metric definition (and obviates the >>>> need >>>> for an imperfect polyfill for counting interactions). >>>> >>>> *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? >>>> n/a >>>> >>>> >>>> *Debuggability* >>>> DevTools has existing support for Interactions (real time performance >>>> monitor and tracing). Visualizing total interactionCount is not needed, >>>> but >>>> can be easily found (via literally counting the list of interactions, or >>>> just console logs). >>>> >>>> *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/event-timing/ (several tests, look for >>>> interaction-count-*) >>>> >>>> *Flag name on about://flags* >>>> *No information provided* >>>> >>>> *Finch feature name* >>>> EventTimingInteractionCount >>>> >>>> *Rollout plan* >>>> Will ship enabled for all users >>>> >>>> *Requires code in //chrome?* >>>> False >>>> >>>> *Availability expectation* >>>> Feature is available on Web Platform Baseline within 12 months of >>>> launch in Chrome (as part of Interop 2025 for INP) >>>> >>>> *Adoption expectation* >>>> Polyfill already widely adopted (for INP calculation), and feature >>>> detection already used. >>>> >>>> *Estimated milestones* >>>> Shipping on desktop 143 >>>> DevTrial on desktop 111 >>>> Shipping on Android 143 >>>> DevTrial on Android 111 >>>> Shipping on WebView 143 >>>> >>>> *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). >>>> Already specced in Event Timing API. >>>> >>>> *Link to entry on the Chrome Platform Status* >>>> https://chromestatus.com/feature/5153386492198912?gate=5819984274128896 >>>> >>>> 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/CAEeF2TfFNGGAvfWM0cbTXG%2B5G4-_Uud5eGQi%3DZ5r2A1%2BwCskEg%40mail.gmail.com >>> >>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAEeF2TfFNGGAvfWM0cbTXG%2B5G4-_Uud5eGQi%3DZ5r2A1%2BwCskEg%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/7d072c7e-776f-45fd-b715-59041d8afb20n%40chromium.org.
