Syntax Highlighting

Disable Rouge

By default Jekyll uses Rouge as syntax highlighter. In some cases, you may want to disable it. To get Rouge disabled in Jekyll, just add the following in line(s) _config.yml.

Not using GitHub Pages:

highlighter: none

Using GitHub Pages:

markdown: kramdown
kramdown:
  syntax_highlighter_opts:
    disable : true

Source: https://www.ronaldsvilcins.com/2018/02/05/disable-jekylls-default-syntax-highlighter-rouge/