For those of you who have blogs with lots of image and video content, this is certainly one of the right solutions to increase blog loading by installing LazySizes because image or video content will not be loaded (off-screen) before you scroll down the page.
All right, for those of you who want to add it, please follow the steps below:
How to Increase Blog Loading with Lazy Sizes
The first step, open Blogger > Click the Themes menu > Click Edit HTML > Then add the code below before </body>
<script>
//<![CDATA[
// LazySizes https://github.com/aFarkas/lazysizes
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//]]>
</script>LazySizes on Pictures
Next, to apply, please search for everything img in the theme.
<img...<img src='//www.blogger.com/img/icon_delete13.gif'/><img class='lazyload' src='//www.blogger.com/img/icon_delete13.gif'/><img class='blogger lazyload' src='//www.blogger.com/img/icon_delete13.gif'/><img class="lazyload" alt="Kezel Responsive Blogger Template" style="border: none;" data-original-height="853" data-original-width="1494" height="365" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiAzl50bP4qOY379ESTU4f_JYw_N3zxYkzcyajxgLc7egIG6odulY16IgkMMRVSA5k41keST-Rsw1Y09Nq-cqLRhtJznFae3j3OmSdzfWCs7vYIgtO_1012VqH8DJMzgl85uGpsOeWHyNEX/s640/Kezel+Responsive+Blogger+Template.png" title="Kezel Responsive Blogger Template" width="640" /><img class="lazyload" alt="Kezel Responsive Blogger Template" style="border: none;" data-original-height="853" data-original-width="1494" height="365" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiAzl50bP4qOY379ESTU4f_JYw_N3zxYkzcyajxgLc7egIG6odulY16IgkMMRVSA5k41keST-Rsw1Y09Nq-cqLRhtJznFae3j3OmSdzfWCs7vYIgtO_1012VqH8DJMzgl85uGpsOeWHyNEX/s640/Kezel+Responsive+Blogger+Template.png" title="Kezel Responsive Blogger Template" width="640" />Actually, for better application, it's better if you replace the src image with data-src Blogger, but for the new version of Blogger it turns out that it hasn't worked wellResult
LazySizes on Video
Next apply it to the video iFrame. Just like in the picture, in the iFrame video to add it here I give an example on this Youtube video iFrame<iframe width="560" height="315" src="https://www.youtube.com/embed/pVCIZhGJ4gM" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe><iframe class="lazyload" width="560" height="315" data-src="https://www.youtube.com/embed/pVCIZhGJ4gM" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>That's the Way to Increase Blog Loading with LazySizes that Sayem Tutorial can share this time. Hopefully useful and respectful.
Source: https://github.com/aFarkas/lazysizes
