Alvaro

<a href="https://gutenberg-showcase.melonpan.io/melonpan-block-code" rel="nofollow ugc">Demo</a> – <a href="https://melonpan.io/wordpress-plugins/melonpan-block-code" rel="nofollow ugc">Documentation</a> – <a href="https://github.com/garciaalvaro/melonpan-block-code" rel="nofollow ugc">GitHub</a>
Block to display code, with highlighted syntax, which can be copied to the clipboard.
<h3>Features</h3>
The block comes with the following settings:
<ul>
<li>Code language: JavaScript, CSS, PHP, etc. <a href="https://prismjs.com/#languages-list" rel="nofollow ugc">Full list of languages</a>.</li>
<li>Color theme</li>
<li>Label: Top left label that can be customized. By default the code language.</li>
<li>Copy button: Top right button to copy the block content.</li>
<li>Padding</li>
<li>Border width and Border radius</li>
</ul>
<h3>Usage</h3>
The block can be found inside the blocks inserter menu under the Melonpan Blocks category. 
Once added in the post you can edit its settings on the Editor sidebar under the Block settings panel. 
Switch between the previewer and editor views to edit the code and see its styled output.

Melonpan Block – Code

Block to display code, with highlighted syntax, which can be copied to the clipboard.

Nico

Despite two plugins already on wordpress.org I decided to write my own from scratch. The result is a minimalistic but powerful plugin with only ~250 lines of PHP.
<ul>
<li>Supports every possible Prism configuration.</li>
<li>Adds TinyMCE dropdown lost for <code><code class="language-xxx"> and <pre class="language-xxx"></code> for bash, css, js, markup, php, scss. (I can make a filter if you want to add more.)</li>
<li>Does not load prism on every page, only when needed.</li>
<li>Supports automatic detection of prism HTML.</li>
<li>Supports displaying code from custom fields with <code>[prism]</code> shortcode.</li>
<li>Developers may use the <code>prism</code> handle to enqueue the pre-registered script and style.</li>
<li>Has admin editor button for quick shortcode template snippet.</li>
<li>Has no options page by design.</li>
<li>Read more -> <a href="http://nextgenthemes.com/plugins/prism-syntax-highlighter-for-wordpress/" rel="nofollow ugc">Prism Syntax Highlighter for WordPress</a></li>
</ul>
Bundled Prism Version (2016-09-17)
Link: http://prismjs.com/download.html?themes=prism-okaidia&languages=markup+css+clike+javascript+bash+less+php&plugins=line-highlight+line-numbers+wpd+show-language
Skin: Okaida
Languages
<ul>
<li>Markup</li>
<li>CSS</li>
<li>C-like</li>
<li>JavaScript</li>
<li>Bash</li>
<li>PHP</li>
<li>Sass (Scss)</li>
</ul>
Plugins
<ul>
<li>Line Highlight</li>
<li>Line Numbers</li>
<li>WebPlatform Docs</li>
<li>Show Language</li>
</ul>

Prism Syntax Highlighter for WordPress

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Most lightweight, yet most configurable and advanced PrismJS WordPress integration plugin. Custom fields display (detached) supported.

Melonpan Block – Code vs Prism Syntax Highlighter for WordPress