Code QuizAdvanced

Observing LCP with PerformanceObserver

Spot the bug in a PerformanceObserver setup meant to measure Largest Contentful Paint.

Codejavascript

const observer = new PerformanceObserver((list) => {
  for (const entry of list.getEntries()) {
    console.log('LCP candidate:', entry.startTime);
  }
});

observer.observe({ type: 'largestContentfulPaint', buffered: true });

This code should log Largest Contentful Paint entries but never fires. What is the bug?

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