Nikul Patel

Assertivlogix Simple Cache is a lightweight WordPress plugin that improves front-end performance by caching rendered pages and minified CSS/JS assets to reduce server load and page load times.
<ul>
<li>New: Optional lazy loading for <code><img></code> tags. Enable the checkbox in the plugin settings to automatically append <code>loading="lazy"</code> to cached HTML when your theme or host does not already handle it.</li>
<li>Advanced CSS controls: remove unused selectors and duplicates, combine local stylesheets into an async-delivered bundle, and inline auto-generated or manual critical CSS for faster first paint.</li>
</ul>
<h3>Compatibility</h3>
This plugin relies on <code>ob_start()</code> buffering and is not supported on servers that already provide full-page caching at the base/server level (e.g., managed hosts with Varnish, LiteSpeed cache services, or proprietary edge caches). Combining two page caches can cause double-caching, stale pages, or broken purge flows, so we cannot offer support for those environments.

Assertivlogix Simple Cache

Lightweight caching plugin by Assertivlogix that caches pages, CSS, and JS files for faster performance.

digitalapps

This plugins detects all of the styles queued via wp_enqueue_style. Contents of each css file are copied and stored in a single css file. This file is loaded on the frontend. The plugin wp_dequeue_style and wp_deregister_style all other css files. The result is your website only makes one single http request to load css styling. Bonus feature the contents of the css file are minified.
Simply flip the switch and the plugin will do the rest.
NOTE: I have only tested this plugin on my own sites running the AdSense Theme. If you encounter a problem with this plugin please let me know. I will be able to help you.

WP CSS Merge

This plugins detects all of the styles queued via wp_enqueue_style. Contents of each css file are copied and stored in a single css file.

Assertivlogix Simple Cache vs WP CSS Merge