coreyti/showdown — pull request #87 by boneskull (2014-02-17 07:58:00+00:00)
Title: explicitly put Showdown in window object if detected

This means that the extensions will not have any problem attaching themselves to Showdown. If Showdown is **not** in the `window` object, the extension will not find Showdown, not register itself, and Showdown will raise an exception because the extension you specified does not exist.