GDN version 1.4+
This filter is used in Meta Category. You can change category items in meta.
function my_meta_categories($categories){ foreach($categories as $key => $category){ if($category->parent > 0){ unset($categories[$key]); } } return $categories; } add_filter( 'jaw_meta_categories', 'my_meta_categories',10 );In meta will be shown only main categories (not childs)
List of all hooks you can find HERE