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                <div class="container my-4">

<h1>Defer image loading script</h1>
<p>If you have large images in a carousel, it would be a good idea to defer loading them. This will increase your page load time. This scripts adds a base 64 image placheholder in the html and then uses javascript to replace that with the actual image source. So the document loads and then loads in the images.</p>
      <a href="">How to simulate a slow connection in Google DevTools</a>
<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAABlBMVEXR0dG/v7+g+VsXAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAACklEQVQImWNgAAAAAgAB9HFkpgAAAABJRU5ErkJggg==" data-src="" class="img-defer">




Create base 64 images
.img-defer {
   /*  Set a min-height of image   */


function init() {
var imgDefer = document.getElementsByClassName('img-defer');
for (var i=0; i<imgDefer.length; i++) {
if(imgDefer[i].getAttribute('data-src')) {
} } }
window.onload = init;