Header Footer Code Manager by Draftpress is a easy interface to add snippets to the header or footer or above or below the content of your page.
Query Migrate is a javascript library that allows you to preserve the compatibility of your jQuery code developed for versions of jQuery older than 1.9.
jQuery is a JavaScript library which is a free, open-source software designed to simplify HTML DOM tree traversal and manipulation, as well as event handling, CSS animation, and Ajax.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Priority Hints exposes a mechanism for developers to signal a relative priority for browsers to consider when fetching resources.
WordPress is a free and open-source content management system written in PHP and paired with a MySQL or MariaDB database. Features include a plugin architecture and a template system.
WP Rocket is a caching and performance optimisation plugin to improve the loading speed of WordPress websites.
Yoast SEO is a search engine optimisation plugin for WordPress and other platforms.