The IntersectionObserver method unobserve() instructs the IntersectionObserver to stop observing the specified target element.

target

The Element to cease observing. If the specified element isn't being observed, this method does nothing and no exception is thrown.

None (undefined).

This snippet shows an observer being created, an element being observed, and then being unobserved.

const observer = new IntersectionObserver(callback);
observer.observe(document.getElementById("elementToObserve"));

// …

observer.unobserve(document.getElementById("elementToObserve"));

• Intersection Observer API
• IntersectionObserver.observe()