[Koha] Enable single branch mode in Koha 3.12

Hi All I was going through the Koha Implementation checklist. Under Admin, there is on section that related to " Enable single branch mode (sys pref = singleBranchMode) " which is said to have the implication of " This is only applicable for single location sites and enabling it eliminates the branch selection limits / facets in the OPAC " I am trying to locate where this setting can be made. Any pointers? Regards, Admire