Intersection Observer & Efficient Scroll Handling

What is the purpose of the isIntersecting property in the IntersectionObserverEntry?

const callback = (entries) => {
  entries.forEach(entry => {
    if (entry.isIntersecting) {
      console.log('Element has entered the root');
    } else {
      console.log('Element has left the root');
    }
  });
};

To check if the observer is active
To measure scroll speed
To determine if the target element intersects with the root
The isIntersecting property is a boolean that indicates whether the target element intersects with the root element (or viewport). It's crucial because: 1) It provides a simple way to determine if an element is visible without complex calculations, 2) It helps distinguish between enter and exit events, 3) It's more reliable than checking intersectionRatio > 0 as it accounts for edge cases, 4) It's commonly used as a primary condition for triggering actions like lazy loading or animations. This property is particularly useful for implementing one-time actions when elements become visible.
To validate observer configuration

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