Load jQuery UI attribute issue in Concrete5.5.1Browser Info Environment
It may be that the jquery.ui code you had written/included is now conflicting with something in the C5 dashboard (which works in a different way).
Another possibility is if your jquery code was not inside a document ready, and the timing/sequencing of loads will have changed with 5.5.1
If you are in chrome or firefox, please look at the developer console and see if you are getting any jquery errors.
If that doesn't help, then please PM the URL and a temporary admin login and I will have a look.
The multiple loads should not have happened. addHeaderItem is only supposed to add each header item once.
Nevertheless, I have updated Load jQuery.UI (v1.2) to skip the addHeaderItem part if a user is logged in. This removes the opportunities for bugs in other code to interfere with what Load jQuery.UI does.