Chris A. a11n

<p>Backwards Compatible Permalinks helps prevent 404 errors when switching between permalink structures.</p>
<p>It achieves this by appending a set of backwards compatible post rewrite rules. This ensures posts are still accessible at their previous permalink after the permalink structure is updated.</p>
<h4>Example</h4>
<p>Let’s say your permalink structure is set to “Month and name” and you have a post titled “I Love WordPress.” That particular post would live at <code>https://example.com/2019/03/i-love-wordpress/</code>.</p>
<p>But what if you wanted to switch to the “Post name” permalink structure and have your post live at <code>https://example.com/i-love-wordpress/</code> instead?</p>
<p>You could but this would result in the existing post permalink 404ing when visited. Which is problematic if the previous URL was bookmarked or shared on social media.</p>
<p>With Backwards Compatible Permalinks installed your post would be accessible at both the old and new permalink structures:</p>
<ul>
<li><code>https://example.com/2019/03/i-love-wordpress/</code></li>
<li><code>https://example.com/i-love-wordpress/</code></li>
</ul>
<h4>Caveats</h4>
<ul>
<li>This plugin does not work retroactively. i.e. you must have the plugin installed and activated prior to switching permalink structures before backwards compatibility will work.</li>
<li>Currently only standard posts are supported.</li>
<li>Backwards compatibility is not supported between certain permalink structure updates. This is due to a clash between permalink structure regex matching.</li>
<li>Backwards compatibility is only provided between the most recent permalink structure update. i.e. you cannot change your permalink structure 3 times and have backwards compatibility across all 3 structures.</li>
</ul>
<h4>Deactivate or uninstall</h4>
<p>After deactivating or uninstalling this plugin please ensure you visit Settings > Permalinks in the WordPress admin area to flush your rewrite rules.</p>
<h4>Contributing</h4>
<p>Contributions are <a href="https://github.com/aprea/backwards-compatible-permalinks" rel="nofollow ugc">welcomed on GitHub</a>.</p>
<h3>From within WordPress</h3>
<ol>
<li>Visit ‘Plugins > Add New’.</li>
<li>Search for ‘Backwards Compatible Permalinks’.</li>
<li>Activate Backwards Compatible Permalinks from your Plugins page.</li>
</ol>
<h3>Manually</h3>
<ol>
<li>Upload the <code>backwards-compatible-permalinks</code> folder to the <code>/wp-content/plugins/</code> directory.</li>
<li>Activate the Backwards Compatible Permalinks plugin through the ‘Plugins’ menu in WordPress.</li>
</ol>


Backwards Compatible Permalinks

Provides a degree of backwards compatibility when switching between permalink structures.

VelvetBlues.com

<p>If you move your WordPress website to a new domain name, you will find that internal links to pages and references to images are not updated. Instead, these links and references will point to your old domain name. This plugin fixes that problem by helping you change old urls and links in your website.</p>
<h4>Features:</h4>
<ul>
<li>Users can choose to update links embedded in content, excerpts, or custom fields</li>
<li>Users can choose whether to update links for attachments</li>
<li>View how many items were updated</li>
</ul>


Velvet Blues Update URLs

Updates all urls and content links in your website.

Backwards Compatible Permalinks vs Velvet Blues Update URLs