I have an issue with my Javascript code and I hope somebody can help me with this.
I created an lazy load function for images.
<script type="text/javascript">
let options = {
  root: null,
  rootMargin: '0px',
  threshold: 0.75
};
let callback = (entries, observer) => {
  entries.forEach(entry => {
    if(entry.isIntersecting && entry.target.className === 'lazy'){
      let imageUrl = entry.target.getAttribute("data-src");
      if(imageUrl){
        entry.target.src = imageUrl;
      }
    }
  });
}
let observer = new IntersectionObserver(callback, options);
lazy = document.querySelectorAll("img.lazy");
for(i=0; i < lazy.length; i++){
  observer.observe(lazy[i]);  
}
</script>
Works for this element
<img data-src="https://www.example.com/image.jpg" src="" class="lazy"/> 
Does not work for this element
<img data-src="https://www.example.com/image.jpg" src="" class="test lazy"/>
The differents between these both elements are one has an extra class test
How can I fix this issue in my Javascript code?
 
    