import type { RumConfiguration } from '../domain/configuration'; /** * first-input timing entry polyfill based on * https://github.com/GoogleChrome/web-vitals/blob/master/src/lib/polyfills/firstInputPolyfill.ts */ export declare function retrieveFirstInputTiming(configuration: RumConfiguration, callback: (timing: PerformanceEventTiming) => void): { stop: () => void; };