nicmare

Did you know that WordPress generates a thumbnail image file when uploading a PDF-file? This works when the PHP Extension imagick and Ghostscript is available! It won’t work with GD library! You know they are present and it’s working, when you upload a PDF-file in the media library and you immediately see a thumbnail of the file. Now that thumbnails are available my plugin hooks into the Gutenberg file-block to automagically inserting that thumbnail right before the file block. Besides that it also provides some more options:
<h3>Plugin Features</h3>
<ul>
<li>a toggle to insert an preview image before the file block</li>
<li>a toggle to link the preview image with the “link to” settings value of the file block</li>
<li>a toggle to link the preview image with itself to the full-size image</li>
<li>a toggle to enable the Lightbox-Effect on the preview image (enable in settings)</li>
<li>a setting to choose the size of the preview image: thumbnail, medium, large</li>
<li>a settings page to define default for image size and <code>show inline embed</code> default value and a <code>height in pixels</code> default value</li>
<li>when activating the plugin, the <code>show inline embed</code> option of the file block gets disabled by default</li>
<li>the preview image link target is based on setting of file-block (<code>open in new tab</code>)</li>
<li>adds new block styles to file block with just a few inline css code</li>
<li>this plugins main goal is to be very lightweight and avoid loading any additional assets and saving DOM performance. It just uses 3 files. </li>
</ul>
This plugin requires imagick and Ghostscript! A good WordPress web hosting has it installed by default.

PDF-Preview inside File-Block

Extends the core/file block to optionally insert a PDF preview image (generated by WordPress) before the file block and adds linking/lightbox options.

Marco Milesi

WP Attachments enhances the download experience and file management in WordPress. It automatically displays attachments in your posts and pages, so you don’t need to manually insert download links. 
Easily attach, unattach, or reattach files directly from the media library.
Key Features: 
– 🤖 Automatically displays attachments after post content 
– ℹ️ Backend metabox for managing attachments 
– 🔃 Quick Attach, Unattach, and Reattach actions in the Media Library 
– 🔢 Download counter with anti-spam and logged-in user filtering 
– 🧑‍💻 Developer hooks and filters for customization 
– 🛍️ WooCommerce compatible 
– 🎨 Five icon packs to choose from 
– 📜 Supports posts, pages, and custom post types 
– 🎢 Customizable themes (title, date, size, caption, and more)
<a href="https://www.youtube.com/watch?v=J7gf0hxl_z8" rel="nofollow ugc">Video Overview</a>
<h3>Contributions</h3>
<ul>
<li>Part of <a href="http://www.wpgov.it" rel="nofollow ugc">WPGov.it</a>, providing open source solutions for Italian Public Government websites.</li>
<li>Thanks to the Italian community <a href="http://www.porteapertesulweb.it" rel="nofollow ugc">Porte Aperte sul Web</a> for beta testing and ideas.</li>
<li>Metabox based on <a href="https://wordpress.org/plugins/ij-post-attachments/" rel="ugc">IJ Post Attachments</a></li>
<li>Some icons by <a href="http://p.yusukekamiyamane.com/" rel="nofollow ugc">Yusuke Kamiyamane</a>.</li>
</ul>

WP Attachments

Nice and useful plugin. The only downside is that it lacks a setting to show image thumbnails instead of a generic image icon in the edit metabox.

Show thumbnails instead of icons in metabox

A powerful solution to manage and display your WordPress media attachments in posts and pages.

PDF-Preview inside File-Block vs WP Attachments