aggiungere in backend le tassonomia custom su custom post e post normali
<?php
// manage_taxonomies_for_{$post_type}_columns
add_filter( 'manage_taxonomies_for_activity_columns', 'activity_type_columns' );
function activity_type_columns( $taxonomies ) {
$taxonomies[] = 'activity-type';
return $taxonomies;
}
?>