The default metaboxes are registred in the file wp-admin/includes/meta-boxes.php
. There you can find the function post_categories_meta_box()
which will generate the taxonomy metabox. Currently there is no hook available to filter the output. But you can do one of the following:
- Use
remove_meta_box()
to remove the existing category metabox and register your own withadd_meta_box()
. Copy&Past the existing code to your new metabox function and remove the code block from line345
to367
. - The cleaner way: Remove the
edit_terms
capability from your user roles withremove_cap()
. If you look in the metabox function, on line345
you can see an if-statement which checks if the user has the capabilityedit_terms
. If so, the+ Add New XY
will be displayed. Problem here, the name of the capability is dynamic and could be anything. If someone registers a taxonomy with a different capability naming, this will probably not work (untested).