bypr.nils

Smart Image Loader loads images which are visible in the initial viewport of your website before any images whose position is “below the fold”, outside the current viewport. Those images can be loaded as soon as the visible images are finished loading or “lazy loaded” when they would become visible. This can be useful for bandwidth saving on mobile devices.
There is no need to insert any additional code into your website, just install the plug-in.
The default settings are fine in most cases, but you may want to adjust them for optimization.
Smart Image Loader is tested and works down to Internet Explorer 7, disabled below.
Note: there is currently no support for (CSS) background images.

Smart Image Loader

Smart Image Loader is a fire-and-forget priority and lazy loader for image sources. Can be a huge performance boost especially for one pagers.

Frank Goossens

Deny Dias

This plugin extends Autoptimize to automatically create critical CSS rules. These rules inject the correct critical CSS in different types of pages to ensure these pages are rendered even before the full CSS is loaded, improving the “start to render time” and user experience. For this purpose the plugin integrates with criticalcss.com, a 3rd party service, to have it generate the critical CSS (see <a href="https://wordpress.org/plugins/autoptimize-criticalcss/#faq">FAQ for info on pricing</a>).
Simply install and activate the plugin (you will need to have Autoptimize up and running), enter your <a href="https://criticalcss.com/?aff=1" rel="nofollow ugc">https://criticalcss.com</a> API key and the plugin will automatically start work to create rules.
If you want to change settings or review the rules, you can find these by clicking the “critical css” tab on the Autoptimize plugin settings screen. There are “installation instructions” and more info in <a href="https://wordpress.org/plugins/autoptimize-criticalcss/#faq">the FAQ</a>.

Autoptimize criticalcss.com power-up

Its configuration definitely has a learning curve, but when you get the hang of it, this plugin becomes essential to your website!

Close to perfect

Autoptimize criticalcss.com power-up adds automated critical css creation to Autoptimize integrating with the https://criticalcss.com service.

Smart Image Loader vs Autoptimize criticalcss.com power-up