Peadig

rel=”external” is now the XHTML valid version that informs search engine spiders that the link is external. However, using this does not open the link in a new window. target=”_blank” and target=”_new” does this, but is not XHTML valid.
This very simple plugin adds a small JS file to your header to let this happen!
<ul>
<li><a href="http://pleer.co.uk/wordpress/plugins/rel-external/" rel="nofollow ugc">rel=”external”</a> plugin homepage.</li>
<li>More <a href="http://pleer.co.uk/wordpress/plugins/" rel="nofollow ugc">WordPress Plugins</a>.</li>
<li><a href="http://pleer.co.uk/wordpress/plugins/facebook-comments/" rel="nofollow ugc">Facebook Comments</a> Plugin</li>
<li><a href="http://pleer.co.uk/wordpress/plugins/wp-twitter-feed/" rel="nofollow ugc">Twitter Feed</a> Plugin</li>
<li><a href="http://twitter.com/alexmossSEO" rel="nofollow ugc">Follow @alexmossSEO on Twitter</a>.</li>
<li><a href="http://alex-moss.co.uk/" rel="nofollow ugc">Alex Moss</a>.</li>
<li><a href="http://pleer.co.uk/" rel="nofollow ugc">Pleer SEO</a>.</li>
</ul>

rel=”external” in a New Window

Opens a new window with rel="external" instead of having to use target="_blank" or target="_new"

NewCodeByte

Take full control of your WordPress site’s links with Smart External Links Manager! 
The professional solution for managing external links on modern WordPress sites. Reliably handles dynamic content (AJAX, infinite scroll) and gives you complete control over SEO and style.
This powerful plugin ensures all external links open in a new browser window or tab, enhancing user experience and keeping visitors on your site longer. Built with SEO best practices and XHTML Strict compliance in mind, it offers a seamless integration for both users and search engines.
Its highly configurable settings panel allows you to precisely tailor link behavior to your needs. The core mechanism uses JavaScript to open links, the preferred method for XHTML 1.0 Strict compliance, avoiding <code>target</code> attribute modifications that could invalidate your markup. If JavaScript is disabled, links gracefully open in the current window. 
Ideal for blogs, affiliate sites, magazines, and business websites that rely heavily on external links.
<h3>Who is this plugin for?</h3>
<ul>
<li>Bloggers and Content Creators who want to improve user engagement.</li>
<li>Affiliate Marketers who need to manage rel=”sponsored” and “nofollow” attributes correctly.</li>
<li>Website owners using modern themes with infinite scroll or AJAX-loaded content.</li>
<li>Developers who need a reliable, XHTML Strict compliant, and lightweight solution for their clients.</li>
<li>Anyone who wants a simple, set-and-forget tool to manage external links professionally.</li>
</ul>
Key Features Include:
<ul>
<li>Automatic New Tab for External Links: Improve site engagement by default.</li>
<li>Optional Link Icon: Visually indicate links that open in a new tab with a customizable Dashicon or symbol (e.g., 🔗, ↗).</li>
<li>Custom Styling via CSS Class: Optionally add a specific CSS class to modified links, giving you a clean hook to style them exactly as you want from your theme.</li>
<li>Link Tooltip: Option to display a customizable text tooltip on mouse hover for all modified links.</li>
<li>XHTML Strict Compliant: Uses JavaScript for <code>window.open()</code>, preserving markup validity.</li>
<li>Security First: Automatically adds <code>rel="noopener"</code> to all modified links.</li>
<li>SEO Enhancements:
<ul>
<li>UGC Ready: Works seamlessly with WordPress’s default rel=”ugc” on comment links, ensuring best practices for user-generated content.</li>
<li>Option to add <code>rel="noreferrer"</code> for enhanced privacy.</li>
<li>Option to add <code>rel="nofollow"</code> for specific link types.</li>
<li>Option to add <code>rel="sponsored"</code> for paid or affiliate links.</li>
</ul>
</li>
<li>Granular Control with Lists:
<ul>
<li>Force List: Specify URLs or patterns (e.g., internal PDFs, specific pages) that should always open in a new tab.</li>
<li>Ignore List: Define URLs or patterns that should never open in a new tab, even if external (highest priority).</li>
</ul>
</li>
<li>User-Friendly Settings: Intuitive interface to manage all options, including dynamic lists.</li>
<li>Lightweight & Efficient: Designed to be performant and not slow down your site. Dynamically processes new links added via AJAX.</li>
<li>Internationalization Ready: Easily translatable into any language.</li>
</ul>
Why Choose Smart External Links Manager?
<ul>
<li>User Experience: Keep users on your site while allowing them to explore external resources.</li>
<li>SEO Friendly: Proper use of <code>rel</code> attributes (<code>noopener</code>, <code>noreferrer</code>, <code>nofollow</code>, <code>sponsored</code>) without altering <code>href</code> for search engines.</li>
<li>Compliance: Adheres to XHTML Strict standards for modern web development.</li>
<li>Flexibility: Extensive configuration options to suit any website’s needs.</li>
<li>Developer Support: From the creator of NewCodeByte, with a commitment to quality and updates.</li>
</ul>
Future Enhancements Planned: 
* Excluding specific links via CSS selectors. 
* Advanced management for internal link behavior. 
* And much more!
<h3>Support</h3>
If you need help or have a question, the best place to ask is the <a href="https://wordpress.org/support/plugin/smart-external-links-manager/" rel="ugc">support forum on WordPress.org</a> (once the plugin is listed). 
You can also visit <a href="https://newcodebyte.altervista.org" rel="nofollow ugc">NewCodeByte</a> for more information.
Found this plugin useful? Please consider <a href="https://wordpress.org/support/plugin/smart-external-links-manager/reviews/#new-post" rel="ugc">leaving a ★★★★★ review</a>! 
Want to support future development? <a href="https://buymeacoffee.com/codebytewp" rel="nofollow ugc">Buy me a coffee ☕</a>!

External Links Manager – Open new window in a new tab + nofollow, noreferrer

Manage external links: new tabs, add rel attribute nofollow, noopener, noreferrer, sponsored, show icon on/off. SEO, secure, XHTML Strict compliant.

rel=”external” in a New Window vs External Links Manager – Open new window in a new tab + nofollow, noreferrer