When a support staff tries to set a ticket status using the top right corner drop down - in front end, this does not work as the javascript is not using the correct URL. The prefix ATS_ROOT_URL is missing in that case, while it's correctly used in all othrt javascript instance use of $.ajax I found.
I found 3 instances of this:
media/com_ats/js/adm_tickets.js: looks like admin, should work fine
media/com_ats/js/ticket.js, at line 61 and 70, those are the breaking ones.
Best regards