osTicket v1.10 (stable) and Maintenance Release v1.9.15 are now available! Go get it now
I was able to do this in the past in version 1.6 and 1.8 roughly the same way.
I just upgraded to version 1.10 to finally be completely up to date, but I am having some issues implementing this little visual mod.
Basically, we have 3 SLAs that we created, incidents, problems, and change requests, and the headers are just filters for these SLAs.
I was able to add these by making changes to /scp/tickets.php under $nav->addSubMenu, one for each of the 3 new headers.
changes also had to be made to include/staff/tickets.inc.php in the case statement to add a case for each of my headers.
These 2 parts still seem to be the same in version 1.10
I have attached my documentation of changes made to see if it would help any of you figure out where it is now...