Ajit Kumar Satpathy

These must be in function.php in the theme for the plugin to work for thumbnail and excerpt:
add_theme_support( ‘post-thumbnails’ );
set_post_thumbnail_size( form_option(‘thumbnail_size_w&&echo=false’), form_option(‘thumbnail_size_h&&echo=false’), true );
function custom_excerpt_length( $length ) { 
 return 20; 
} 
add_filter( ‘excerpt_length’, ‘custom_excerpt_length’, 999 ); 
function custom_excerpt_more( $more ) { 
 return ”; 
} 
add_filter( ‘excerpt_more’, ‘custom_excerpt_more’ );
You’ll also need to add thumbnails to the posts you want visible in the list.
After that, all you need to do is to add the hook [getcatlist 1] (where 1 is a categoy id) to your post.

Category Thumbnail Excerpt

Lists a category with thumbnails,title,excerpt with a read more link

Dan Rossiter

demur

Display your documents beautifully! Document Gallery creates thumbnail galleries for PDFs, Word documents, PowerPoint presentations, and other file types—just like WordPress does for images.
<h4>Key Features</h4>
<ul>
<li>WordPress Block Editor – Insert galleries with a single click, configure visually</li>
<li>Automatic Thumbnails – Generates preview images for documents (PDF, Office files, etc.)</li>
<li>Modern Image Formats – Full support for WebP and AVIF images (WordPress 6.5+)</li>
<li>Flexible Display – Grid or list layout with optional descriptions</li>
<li>Smart Filtering – Show all attachments, current post only, or specific documents</li>
<li>Pagination Support – Handle large document libraries efficiently</li>
<li>Fully Customizable – Control columns, sorting, links, and styling</li>
<li>Classic Shortcode – <code>[dg]</code> shortcode available for template use</li>
</ul>
<h4>Perfect For</h4>
<ul>
<li>Document libraries and resource centers</li>
<li>Portfolio and work sample galleries</li>
<li>Publication and whitepaper collections</li>
<li>Course materials and downloads</li>
<li>Legal document repositories</li>
</ul>
<h4>Block Editor Integration</h4>
Click the ‘+’ button in the editor and search for “Document Gallery” to insert a gallery block. All configuration options appear in the sidebar—no shortcode knowledge required. Select specific documents or let the gallery auto-populate based on your criteria.
<h4>Shortcode Support</h4>
The classic <code>[dg]</code> shortcode continues to work perfectly for template files, widgets, and power users who prefer code-based configuration. See the Installation tab for all available options.
<h4>Developer Friendly</h4>
Document Gallery provides extensive filters and actions for customizing thumbnail generation, HTML output, and gallery queries. See the Installation tab for complete developer documentation.
<h4>Partners</h4>
<ul>
<li>WP Real Media Library: Document Gallery seamlessly integrates with RML by way of a 
<a href="https://wordpress.org/plugins/dg-real-media-library/" rel="ugc">helper plugin</a>.</li>
</ul>
<h4>Translation</h4>
Document Gallery has to-date been translated into 6 languages, listed below.
<ul>
<li>Finnish — Thanks, <a href="https://wordpress.org/support/profile/villevetela" rel="ugc">villevetela</a>!</li>
<li>French — Thanks, Marc Liotard and <a href="http://www.trafic-influence.com/" rel="nofollow ugc">Traffic Influence</a>!</li>
<li>Russian — Thanks, <a href="https://wordpress.org/support/profile/demur" rel="ugc">demur</a>!</li>
<li>Spanish — Thanks, Andrew Kurtis and <a href="http://www.webhostinghub.com/" rel="nofollow ugc">WebHostingHub</a>!</li>
<li>Swedish — Thanks, <a href="https://wordpress.org/support/profile/mepmepmep" rel="ugc">mepmepmep</a>!</li>
<li>Ukrainian — Thanks, <a href="https://wordpress.org/support/profile/demur" rel="ugc">demur</a>!</li>
</ul>
<h4>Developers</h4>
Document Gallery includes features intended to make integration with other plugins 
simple. See the bottom of the Installation tab for specific documentation on 
the various features provided.
If this plugin has helped you, please take a moment to <a href="https://wordpress.org/support/view/plugin-reviews/document-gallery#postform" rel="ugc">rate 
it</a>!

Document Gallery

This is an amazing plugin. I suggest updating the readme.txt file. I've tested it with WP 5.8.3 and had no problems.

Amazing plugin and still working without problems

This plugin generates thumbnails for documents and displays them in a gallery-like format for easy sharing.

Category Thumbnail Excerpt vs Document Gallery