Which browser behavior occurs when a ‘passive: true’ flag is used in an event listener?

Question

Web Development — Hard

Which browser behavior occurs when a ‘passive: true’ flag is used in an event listener?

Accepted Answer

Passive event listeners are a performance optimization that tells the browser the listener will not call 'preventDefault()'. This allows the browser to perform scrolling or other default actions immediately without waiting for the JavaScript execution to complete. If 'preventDefault()' is called in a passive listener, the browser ignores it and logs a console warning.