I was having an annoying issue where a site’s menus could not be edited through the WordPress admin interface. The menu structure would load but drag and drop simply refused to work even when the cursor changed to the 4-way move arrow.
I started debugging by commenting out the
add_action() functions enqueuing some extra js files used for the jQuery accordion. That fixed it. Putting back the accordion init script revealed that it was not the problem, so that left the custom jQuery UI file, version 1.8.13.
The latest stable version is now 1.10.2, so I got that by selecting the accordion widget on jQuery UI’s download page, letting the other checkboxes auto populate. Extracted the file into the scripts folder, updated functions.php to point to the new file, and the menus admin page now works again!!
Update the jQuery UI file.