in src/performance/index.ts [117:127]
private getCorePerf() {
if (!this.options.useWebVitals) {
return;
}
this.LCP();
this.INP();
this.CLS();
setTimeout(() => {
this.coreWebMetrics.fmpTime = isNaN(FMP.fmpTime) ? -1 : Math.floor(FMP.fmpTime);
}, 5000);
}