Upgrading to the premium plugin allows you to unload additional pages with unused styles & scripts, such as:
Taxonomy sites, such as default categories for WordPress, tags and custom built ones, such as WooCommerce categories of items.
Author pages (for example, the page that displays all posts published by a particular author, defined by the is author() function)
WordPress Search Page Default
WooCommmerce Search Page (which has the same settings as the actual shop page found via the function is shop()))
404 page (not found): this one is as light as possible and many of the CSS and JavaScript files that are required here (detected through the 404() function) are less likely to be
Date Archive Page: This is any page that retrieves items detected by the date filtered by the is date() feature.
As for loaded JavaScript scripts, it is possible to add attributes such as defer and async.
There are a plethora of techniques that are often used to postpone parsing, but the easy and preferred technique is to simply defer JavaScript loading until it is required. It is next suggested that you use the <script async> attribute if possible, which prevents parsing from blocking the initial page load by deferring it until the browser’s UI thread is not busy doing anything else, if this technique is not suitable to use on your page. With Asset CleanUp Pro, all these settings can be added without writing any code.
Adjust the whereabouts of the CSS/JS files (could be moved from HEAD to BODY to prevent render-blocking or vice-versa if you need early triggering of specific files)
Unload hardcoded CSS/JS (not loaded via the normal WordPress functions such as wp enqueue scripts()). Unload CSS/JS. It was possible to add LINK/STYLE/SCRIPT tags by modifying the PHP code (not using the correct WordPress action hooks), directly within the content of posts, widgets or through plugins such as “Insert Headers and Footers,” “Head, Footer and Post Injections,” etc.
Functionality “Test Mode” Concerned about making optimization errors? No more, don’t be!
This helps you to customize the website (unload useless files, set async, defer to loaded JavaScript files, clean up HTML code) without applying “live” changes (to the daily visitor) if you ever have any concerns that a change could break the page/website functionality. Any improvements you have made can only apply to you (the logged in administrator). When you are pleased with how the page looks and works, “Test Mode” can be disabled to push live improvements so that everyone else can experience faster page loads.