Context: This feature has been implemented behind an experimental status flag for over a year and has had extensive developer testing-- but there was never a dedicated Chrome feature specifically for it created, as it was just part of the larger Event Timing / interactionId (for INP) project.
As part of Interop 2025, other implementers have started to ship this feature and so we want to ship as well. I expect to send I2S shortly, before the m143 branch, but needed to send this first. (Not sure if there was a better expedited process) -Michal On Fri, Oct 17, 2025 at 8:35 AM 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> > > *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 > > *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 > > 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/CAEeF2TeUAGSeFh70mWTFZPp_214%2B%3Db%2BT25aDPkq_Xyb3LRiM9g%40mail.gmail.com.
