Pavel

<p>The “Light Code Block” plugin is a simple and lightweight solution for inserting and displaying code snippets in posts and pages.<br />
It works by adding a custom “LC” button to the TinyMCE (Classic) editor or a code block in the Gutenberg editor.</p>
<p>The inserted code will be shown on the front end in a clean, readable format.</p>
<h3>Usage</h3>
<ul>
<li>Install and activate the plugin.</li>
<li>Go to the post or page edit screen.</li>
<li>In the TinyMCE (Classic) editor, click the <strong>“LC”</strong> button in the toolbar.</li>
<li>In the popup window that opens, paste or write your code, and click <strong>OK</strong>.</li>
<li>Save or update your post.</li>
</ul>
<p>The code will be saved inside a special block and displayed on the front end within a <code><pre></code> tag with the class <code>mce-simple-code-block</code> (i.e., <code><pre class="mce-simple-code-block">...</pre></code>).</p>
<p>To insert code using the Gutenberg editor, you first need to add a Classic (TinyMCE) block, and then use it to insert your code.</p>


Light Code Block

The "Light Code Block" plugin is the simplest and lightest plugin for inserting and displaying code.

redcocker

<p>Just another code syntaxhighligher for the theme and plugin editor with CodeMirror. This plugin can highlight sourcecodes in the theme/plugin editor and provide a useful toolbar.</p>
<h4>Features</h4>
<ul>
<li>Highlight sourcecodes in theme and plugin editor on the dashboard.</li>
<li>Based on Marijn Haverbeke’s “<a href="http://codemirror.net/" title="CodeMirrorr" rel="nofollow ugc">CodeMirror</a>” JavaScript library.</li>
<li>Built-in 10 themes.</li>
<li>Useful toolbar which includes search/replace features.</li>
<li>Full-screen editing.</li>
<li>Auto-complete.</li>
<li>Easy to configure features through the setting panel.</li>
<li>Localization: English(Default), 日本語(Japanese, UTF-8).</li>
</ul>
<h4>Support languages</h4>
<ul>
<li>PHP</li>
<li>CSS</li>
<li>Javascript</li>
<li>(X)HTML</li>
</ul>
<h4>Recommended plugin</h4>
<ul>
<li>“<a href="https://wordpress.org/extend/plugins/wp-syntaxhighlighter/" title="WP SyntaxHighlighter" rel="ugc">WP SyntaxHighlighter</a>” can highlight sourcecodes on your front-end(posts, pages, comments).</li>
</ul>


CodeMirror for CodeEditor

Just another code syntaxhighligher for the theme and plugin editor with CodeMirror.

Light Code Block vs CodeMirror for CodeEditor