I have the REAL fix for this problem. The challenge is the plugin uses an OLD version of the jquery.ui.min.js — jquery’s user interface program that deals with drag-n-drop and other cool functionalities. You’ll find it in this folder:
“/wp-content/plugins/people-lists/js“.
The first step is to rename that original file to something like ‘jquery.ui.min.js.OLD’ to render it useless. Then, we have to go to jquery’s website to find an updated version and upload it to the same folder.
UPDATED VERSION DOWNLOAD
Go to jquery’s site and download an updated version of the jquery.ui.js file:
https://jqueryui.com/download/
At the bottom of the page is an option to include a theme. Select no theme from the dropdown, then press the download button. When you unzip the downloaded file, it contains dozens of files, but we only need one. Drill down into the folder jquery-ui-1.10.3/ui/minified/ to find a fresh version of jquery’s User Interface file. The ‘minified’ means all the extra spaces have been removed from the text in the file to reduce loading time on your website. (Future humanoids: the number may change as newer versions of jquery ui are released, but the location should be the same).
In that folder is jquery.ui.min.js — upload that to the /wp-content/plugins/people-lists/js/ folder on your website and the people list plugin works fine after that. Be sure to check the functionality of any other plugins on your website that might use the jquery UI functions to ensure they’re working normally.
For the techno-weenies, it looks like jquery changed the way they deal with drag-n-drop and some other features, breaking them out into separate functions. The old version of the jquery.ui file doesn’t include the necessary code for it to work with the version of jquery included with WP 3.6.1. Jquery.min.js is called by people-lists.php on about line 334 (the line the poster above suggested removing).This fixes the actual problem.
neXorianus, if you’re thinking about taking this over, you could just bundle an update with the latest version of the jquery.ui.
Hope this helps.