Schema:FirstInputTiming

PHP logging

EventLogging::logEvent( 'FirstInputTiming', 21009211, $event );

extension.json setup for JavaScript logging

{
	"attributes": {
		"EventLogging": {
			"Schemas": {
				"FirstInputTiming": 21009211
			}
		}
	}
}

JavaScript logging

mw.track( 'event.FirstInputTiming', { /* ... */ } );
From Meta, a Wikimedia project coordination wiki
Revision 21009211
description"Holds the First Input Timing information captured by the NavigationTiming extension"
properties
pageviewToken
description"Token unique to current page's JS execution context. Used to link to NavTiming data."
type"string"
processingStart
description"The time the first event handler started to execute."
type"integer"
processingEnd
description"The time the last event handler finished executing."
type"integer"
name
description"The type of event dispatched. E.g. "touchmove". Doesn't require an event listener of this type to be registered."
type"string"
startTime
description"The event timestamp."
type"integer"
duration
description"The duration between |startTime| and the next time we "update the rendering or user interface of that Document and its browsing context to reflect the current state" in step 7.12 in the HTML event loop processing model."
type"integer"
FID
description"First Input Delay (processingStart - startTime)"
type"integer"