[Koha] 3.8.4 staff main page

The first staff page in 3.8.4 after logging in has a tabbed search box at the top that "defaults" to patron checks - our staff has asked me to change this to the fourth/last tab "catalogue" as they cannot find a "preference" anywhere. Does anyone happen to know where the code for this might be found. I had a quick, unsuccessful, look around with firebug, so it would be most helpful if someone could point me towards the relevant perl or template file. Many thanks - Paul