John Dalesandro

Head Trimmer gives you granular control over what WordPress automatically outputs in the HEAD element of every page. Each option is independent; enable only the removals that make sense for your site.
Removing unnecessary HEAD elements reduces page weight, eliminates potential security signatures such as the WordPress version number, and keeps your generated source code clean.
All settings are opt-in. Nothing is removed until you enable it on the Admin → Settings → Head Trimmer screen.
Removal options include:
<ul>
<li>WordPress Version (generator meta tag)</li>
<li>WordPress Version from Script and Style URLs</li>
<li>All Other Version Signatures from Script and Style URLs</li>
<li>Shortlink</li>
<li>Shortlink from HTTP Response Headers</li>
<li>Canonical</li>
<li>Relational Links for Posts Adjacent to Current Post</li>
<li>RSS Feeds (removes head links and disables feed endpoints)</li>
<li>Really Simple Discovery Link for xmlrpc (rsd_link)</li>
<li>Windows Live Writer Manifest File Link (wlwmanifest_link)</li>
<li>oEmbed Discovery Links</li>
<li>REST API Link and REST API Link Header</li>
<li>Emoji Support</li>
<li>Global Styles and SVG Filters (duotone filters)</li>
<li>Gutenberg Block CSS Styles (or optionally set ‘should_load_separate_core_block_assets’ to load block styles only when needed)</li>
<li>Classic Theme CSS Styles (classic-theme-styles)</li>
<li>DNS Prefetch for //s.w.org</li>
<li>DNS Prefetch for Google Fonts //fonts.googleapis.com</li>
<li>jQuery</li>
<li>JavaScript Import Map (added in WordPress 6.5)</li>
<li>Interactivity API (added in WordPress 6.5)</li>
<li>Image Auto Sizes Styles (added in WordPress 6.7)</li>
<li>Speculation Rules (added in WordPress 6.8)</li>
<li>Comment Reply Script (loads only on singular posts and pages where comments are open)</li>
</ul>

Head Trimmer

Selectively remove WordPress version information, feeds, shortlinks, emoji support, scripts, styles, and other automatically generated extras from the …

TechWebUX

Aleksandar Urošević

Head & Footer Code plugin helps you add custom code snippets (JavaScript, CSS, or HTML) to the page even if you are not a programmer. It could be within the <code><head></code> (site verification code for various services, custom styles, meta or Webfont link), right after opening <code><body></code> (pixel tracking, analytics or heatmap code) or just before closing <code></body></code> tag.
Go to Tools → Head & Footer Code in WordPress Dashboard. Insert custom code to HEAD, BODY or FOOTER section (depending on what you have to do).
All magic is done by hooking to WordPress hooks <code>wp_head</code>, <code>wp_footer</code> and <code>wp_body_open</code>.
<blockquote>
💡 Trial Head & Footer Code plugin on a free dummy website before you add it on your project: <a href="https://tastewp.com/new/?pre-installed-plugin-slug=head-footer-code" rel="nofollow ugc">Test It Now!</a>
</blockquote>
Various code snippets are supported, including but not limited to:
<ul>
<li>Google Analytics 4</li>
<li>Google Tag Manager</li>
<li>Google Ads Conversion</li>
<li>Lite Analytics</li>
<li>Facebook/Meta Pixel</li>
<li>Hotjar</li>
<li>FullStory</li>
<li>Google site verification</li>
<li>Bing site verification</li>
<li>Yandex site verification</li>
<li>Alexa site verification</li>
</ul>
<h3>Homepage in Blog Posts mode</h3>
If your WordPress shows the latest blog posts on the homepage, you can also add specific code only for the homepage on Tools → Head & Footer Code (there will be section Head, body and footer code on Homepage in Blog Posts mode)
<h3>Article specific code</h3>
To insert custom code specific for individual article (post, page or custom post type), use article-specific Metabox while editing post/page/custom post type (check out <a href="https://wordpress.org/plugins/head-footer-code/#screenshots" rel="ugc">Screenshots</a>). There choose if that specific code appends to site-wide code defined on Tools → Head & Footer Code, or to replace it.
<h3>Category specific code</h3>
You can also define a Category specific code on each individual category.
Other taxonomies (tag and custom taxonomy) do not have available their specific code, but for them a Global code is used instead.
<h3>Video guide</h3>
<iframe loading="lazy" class="youtube-player" width="750" height="422" src="https://www.youtube.com/embed/Gd41Dv09UC4?version=3&rel=1&showsearch=0&showinfo=1&iv_load_policy=1&fs=1&hl=en-US&autohide=2&wmode=transparent" allowfullscreen="true" style="border:0;" sandbox="allow-scripts allow-same-origin allow-popups allow-presentation allow-popups-to-escape-sandbox"></iframe>
<h3>Do you need our support?</h3>
If Head & Footer Code does not work on your project, please let us know by <a href="https://wordpress.org/support/plugin/head-footer-code/#new-topic-0" rel="ugc">raising a new support ticket</a> in the <a href="https://wordpress.org/support/plugin/head-footer-code/" rel="ugc">Community Forum</a> and describe what does not works and how to reproduce the issue. We will make sure to resolve the issue as soon as possible.
If you find Head & Footer Code useful for your project, please <a href="https://wordpress.org/support/plugin/head-footer-code/reviews/#new-post" rel="ugc">review plugin</a>.
<h3>Features</h3>
<ul>
<li>Multisite and PHP 8.5 compatible!</li>
<li>Set site-wide custom content for:
<ul>
<li>head page section (before the <code></head></code>)</li>
<li>body section (after the <code><body></code>) – Requires WordPress 5.2!</li>
<li>footer page section (before the <code></body></code>)</li>
</ul>
</li>
<li>Homepage in Blog Posts mode:
<ul>
<li>set homepage specific custom code for head, body and/or footer</li>
<li>toggle homepage specific custom code on paged Homepage (page 2, 3, a nd so on)</li>
</ul>
</li>
<li>Set article specific custom code for:
<ul>
<li>head page section (before the <code></head></code>)</li>
<li>body section (after the <code><body></code>) – Requires WordPress 5.2!</li>
<li>footer page section (before the <code></body></code>)</li>
</ul>
</li>
<li>Set category specific custom code for head, body and/or footer of the page</li>
<li>Choose priority of printed custom code to head/body/footer sections (lower number mean far from <code></head></code> and <code></body></code> and closer to <code><body></code>, higher number means closer to <code></head></code> and <code></body></code> and farther to <code><body></code>)</li>
<li>Choose which post types will have enabled article specific head/body/footer fields</li>
<li>Choose should article specific head/body/footer code be appended to site-wide code, or will replace site-wide code</li>
<li>View on Posts/Pages/Custom Post Types listing if article has defined any article specific custom code</li>
<li>Site-wide section is located under Tools > Head & Footer Code</li>
<li>If you have set WP_DEBUG constant in <code>wp-config.php</code> to <code>true</code>, you’ll see site-wide and article specific entries in page source code wrapped to comments.</li>
<li>[NEW] allow unprivileged user roles Editor and Author to manage article-specific code on single site and multisite (disabled by default)</li>
</ul>
<h3>Data stored in database</h3>
General settings (HEAD, BODY, FOOTER global code and priority, Homepage code and behaviour) saves in WordPress option <code>auhfc_settings</code>. 
Each post/page/custom post type specific HEAD, BODY and FOOTER code and behaviour saves to post meta <code>_auhfc</code>. 
Each category specific HEAD, BODY and FOOTER code and behaviour saves to taxonomy meta <code>_auhfc</code>.
During the Uninstall process all these data has been deleted from the database. 
In case you wish to reinstall plugin, DO NOT UNINSTALL IT although Deactivate, then delete the directory <code>/wp-content/plugins/head-footer-code</code> and then reinstall plugin.
<h3>Permissions on Multisite WordPress</h3>
<ol>
<li>Access to Global: only Super Admin and Administrator</li>
<li>Access to Article specific: Super Admin, Administrator; optional: Editor and Author</li>
<li>Access to Category specific: only Super Admin and Administrator</li>
</ol>

Head & Footer Code

This plugin is what exactly I'm looking for to add custom javascript and CSS codes to specific pages without inserting them inside the template.

A must have plugin

Easy add site-wide, category and article specific custom code before the closing </head> and </body>, or after opening <body> tag.

Head Trimmer vs Head & Footer Code