It appears that an out of date version of jQuery has been modified by atlassian and used in the latest version, but is now out of date (older than version 3) and cannot be updated. Is this true, or can it be updated?
From the jQuery file in confluence:
/*! THIS FILE HAS BEEN MODIFIED BY ATLASSIAN. Modified lines are marked below, se arch "Atlassian" */
/*!
* jQ uery JavaScript Library v2.2.4
* http://jquery.com/
*
* Includes Sizzle.js
* http://sizzlejs.co m/
*
* Copyright jQuery Foundation and other contributors
* Released under the MIT license
* http://jquery.org/license