title: What does the isVisible property mean in intersectionObeserver API?
body: <p>Before lynching me in the comments hear me out. </p>
  
  <p>The intersectionobserver is supposed to listen for when an element is scrolled into view right? </p>
  
  <p>But when I do so the isVisible property is false, cant figure out why. I think its because Im not understanding isVisible property because the other properties are working. </p>
  
  <p>Here is my code: </p>
  
  <pre><code>import React, { useRef, useEffect, useState, useContext } from 'react'
  import ReactGA from 'react-ga';
  import Context from '../utils/context'
  
  
  const Home = props =&gt; {
    const context = useContext(Context)
    const [scrollState, setScroll] = useState(false)
    const intersectTarget = useRef(null)
  
    useEffect(() =&gt; {
      // ReactGA.pageview(props.location.pathname);
      if(!context.initialLoadProp) {
        context.setInitialLoadProp(true)
      }
    }, [])
  
    useEffect(() =&gt; {
      const opts = {
              root: null,
              rootMargin: '0px',
              threshold: 0
      }
      const callback = entry =&gt; {
          console.log(entry)
      }
      const observerScroll = new IntersectionObserver(callback, opts)
  
      observerScroll.observe(intersectTarget.current)
    }, [])
  
    return(
      &lt;div&gt;
        &lt;img height="500px"
             width="500px"
             src="https://timedotcom.files.wordpress.com/2019/03/kitten-report.jpg" alt=""/&gt;
        &lt;div id="heading1" style={{height: '500px'}}&gt;
          &lt;h1&gt;First Heading&lt;/h1&gt;
        &lt;/div&gt;
        &lt;div style={{height: "500px"}}&gt;
          &lt;h1 ref={intersectTarget}
              id="heading2"&gt;
            Second Heading
          &lt;/h1&gt;
        &lt;/div&gt;
      &lt;/div&gt;
    )
  };
  
  export default Home;
  
  </code></pre>
  
  <p>My output even thought isIntersecting is true isVisible is false. </p>
  
  <p><a href="https://i.stack.imgur.com/d2ZlD.png" rel="noreferrer"><img src="https://i.stack.imgur.com/d2ZlD.png" alt="enter image description here"></a></p>