Google Chrome by default to defer loading of images and iframes in the below-fold until user scrolls closer to them. The feature also known as lazyloading, primarily focuses on mobile, but also to be available on desktop later, when shipped, reduces data use, memory and speeds up above-fold content, Google says in a intent to ship thread.
Google employee Scott little says “Deferred content will start loading when the user scrolls with in a particular distance of it.” The feature to be supported on Windows, Mac, Linux, Chrome OS, Android, and Android WebView. Lazy loading of images to use Image replacement in Blink.
Mozilla and Microsoft have shown no interest in this, but Apple has offered public support.
Enable lazy loading for iframes and images in Chrome
To test the feature right away
1. Ensure you’re visiting latest Chrome Canary
2. Visit chrome://flags page.
3. Find and turn on the below two flags and relaunch the browser
Enable Lazy image loading
Enable lazy frame loading
You can find about this on Chrome platform status dashboard here. What this means to end user is that he below-fold content such as images, iframes (banner ads) won’t be downloaded or loaded until they’re visible in the viewport. You can relate this to date saver feature in Android.
Update April 07, 2019: Google Engineer Addy Osmani, in a blog post confirmed they’re looking to ship lazy loading with Chrome 75.