Obviously, deleting superfluous citation formats in the templates cannot be called a satisfying solution. Neither to “remove them entirely from their subdirectories in plugins/citationFormats” (as proposed in another thread). In the long term it doubtlessly will be necessary to enable journal managers to eliminate superfluous citation formats by unchecking the boxes on the “installed plugins” page.
Does anyone please have an estimation about when this will happen? Is it scheduled for OJS 3.1?