Not TestedTesting not done, may not work properly

Performance Observer

Observe real-time metric entries (paint, layout-shift, resource) as they occur.

Checking support...

Interactive Input Workspace

Input Text / Data Payload:

Ready for input

Web API Execution Output

Result output will be displayed here after processing...

Native JavaScript Code Example (Zero Libraries)

const observer = new PerformanceObserver((list) => {
  for (const entry of list.getEntries()) console.log(entry);
});
observer.observe({ entryTypes: ['paint', 'mark'] });

About the Performance Observer Web API

PerformanceObserver interface is used to observe performance measurement events.

Specification:W3C & WHATWG Web API Standard