kioub

With support for the new block editor in WordPress 5.0!
SyntaxHighlighter Amplified allows you to easily post syntax-highlighted code to your site without losing its formatting or making any manual changes. It uses the <a href="https://github.com/scrivo/highlight.php" rel="nofollow ugc">highlight.php package by Geert Bergman</a> to render code on the server-side so it has no depedencies on extrenal Javascript libraries thus is compatible with AMP pages.
For a live demo, see <a href="https://www.javacodegeeks.com/syntaxhighlighter-amplified/" rel="nofollow ugc">this demo page</a>.
For a list of supported languages (most widely used languages are supported), see the <a href="http://en.support.wordpress.com/code/posting-source-code/" rel="nofollow ugc">WordPress.com support document</a>.
Development of this plugin is <a href="https://github.com/kioub78/syntaxhighlighter-amplified" rel="nofollow ugc">on GitHub</a>. See <a href="https://github.com/kioub78/syntaxhighlighter-amplified/issues" rel="nofollow ugc">list of current issues</a> with the plugin. Please feel free to file any additional issues or requests that you may come across. <a href="https://github.com/kioub78/syntaxhighlighter-amplified/pulls" rel="nofollow ugc">Pull requests</a> are welcome.
Translation of the plugin into different languages is on the <a href="https://translate.wordpress.org/projects/wp-plugins/syntaxhighlighter-amplified" rel="nofollow ugc">translation page</a>.
<h4>CREDITS</h4>
This is a fork of <a href="https://github.com/Automattic/syntaxhighlighter" rel="nofollow ugc">SyntaxHighligher Evolved</a> by <a href="https://alex.blog/" rel="nofollow ugc">Alex Mills</a> (Viper007Bond), which is also <a href="https://wordpress.org/plugins/syntaxhighlighter/" rel="ugc">available on WordPress.org</a>. Copyright (c) 2018 Alex Mills. Licensed under GPL 2.0 or later.
<a href="https://github.com/scrivo/highlight.php" rel="nofollow ugc">highlight.php</a> is released under the BSD 3-Clause License. Copyright © 2006-2013, Ivan Sagalaev (maniac@softwaremaniacs.org), highlight.js (original author). Copyright © 2013, Geert Bergman (geert@scrivo.nl), highlight.php

SyntaxHighlighter Amplified

Easily post syntax-highlighted code to your site without having to modify the code at all. Compatible with AMP pages.

michielve

There are other good syntax highlighter plugins, but I wanted something simple and fast and 
be able to add the highlight classes with a select box in the TinyMCE editor.
I added some default languages: Javascript, PHP, Python, C, C#, VB.NET, SQL and CSS but you can 
easily add other ones.

Simple Fast Highlighter

Fast syntax highlighter written in Javascript.

SyntaxHighlighter Amplified vs Simple Fast Highlighter