Intent to prototype: PerformanceEventTiming.interactionId (for INP)

[Nazım Can Altınova]

Summary: PerformanceEventTiming.interactionId is a property that returns an ID uniquely identifying a user interaction and all associated events. It helps measure how long interactions take, identify slow events, and improve web page responsiveness. It is used to calculate the "Interaction to Next Paint" (INP) metric, which is part of Core Web Vitals.

Bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1937572

Specification: https://w3c.github.io/event-timing/#sec-computing-interactionid
Standards Body: W3C
Platform coverage: All
Preference: dom.performance.event_timing.enable_interactionid
Link to standards-positions discussion: https://github.com/mozilla/standards-positions/issues/1069

Other browsers:
* Blink: Shipped since version 96
* WebKit: Considering (https://github.com/WebKit/standards-positions/issues/420)

web-platform-tests: https://wpt.fyi/results/event-timing?label=master&label=experimental&aligned&q=interactionid

Best,

Nazım Can