discourse/discourse — pull request #2204 by ligthyear (2014-03-28 18:43:52+00:00)
Title: Enable autohighlighting of highlight.js for all code blocks

by removing the restriction to only be applied when the user specified a language through the syntax but every time we find a code in a pre-tag. I don't think there is a good case when we want to prevent this from apply ...

See https://meta.discourse.org/t/support-auto-highlighting-for-preformatted-code/14234 .