theMikeD

An excerpt is a (usually) brief, text-only post summary. It is used in various places of a theme when a summary of a post is needed, such as on your blog page and archive pages for terms.
Excerpts are either manually crafted or (usually poorly) automatically extracted from the main post content. Hand crafted ones are better because
<ul>
<li>they avoid things like sentences being cut off in the mid…</li>
<li>they allow you create an actual summary and not just the first x words from the post content</li>
<li>they allow you to do better SEO targeting</li>
<li>they look better</li>
</ul>
This plugin will enforce the use of hand-crafted excerpts by your users by preventing a post without an excerpt from being published.
Classic editor support is based on the work done by Scott Walkinshaw and other contributors, found <a href="https://gist.github.com/swalkinshaw/2695510" rel="nofollow ugc">here</a>.
<h3>Upgrading from a previous version</h3>
Use the upgrade link in the Dashboard (Dashboard > Updates) to upgrade this plugin.
<h3>License and Disclaimer</h3>
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License 2 as published by 
the Free Software Foundation.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
The license for this software can be found here: <a href="http://www.gnu.org/licenses/gpl-2.0.html" rel="nofollow ugc">http://www.gnu.org/licenses/gpl-2.0.html</a>

Mandatory Excerpts for WordPress

Causes the excerpt to be required before a post can be published. Supports both editor types (classic and block aka gutenberg).

WPKube

FancyThemes

This plugin adds several improvements to WordPress’ default way of creating excerpts.
<ol>
<li>Keeps HTML markup in the excerpt (and you get to choose which tags are included)</li>
<li>Trims the excerpt to a given length using either character count or word count</li>
<li>Only the ‘real’ text is counted (HTML is ignored but kept)</li>
<li>Customizes the excerpt length and the ellipsis character that are used</li>
<li>Completes the last word or sentence in an excerpt (no weird cuts)</li>
<li>Adds a read-more link to the text</li>
<li>Ignores custom excerpts and use the generated one instead</li>
<li>Theme developers can use <code>the_advanced_excerpt()</code> for even more control (see the FAQ)</li>
</ol>
Most of the above features are optional and/or can be customized by the user or theme developer.
Banner image credit – <a href="https://www.flickr.com/photos/chillihead/" rel="nofollow ugc">chillihead</a>
Original plugin author – <a href="https://profiles.wordpress.org/basvd" rel="nofollow ugc">basvd</a>
Useful Resources
<ul>
<li><a href="https://fancythemes.com/what-is-wordpress/" rel="friend nofollow ugc">What is WordPress</a></li>
<li><a href="https://fancythemes.com/wordpress-themes" rel="friend nofollow ugc">Fee Themes</a> and <a href="https://fancythemes.com/wordpress-plugins/" rel="friend nofollow ugc">plugins</a></li>
</ul>

Advanced Excerpt

Control the appearance of WordPress post excerpts

Mandatory Excerpts for WordPress vs Advanced Excerpt