Bug when editing custom post type category?

When editing categories for my custom post type the selected admin menu is the one for posts (see screenshot). Is this a bug. If not it’s kind of non intuitive, and not so good for the end users experience.

Screenshot

Code:

function product_register_product_post_type() {

    $box_post_type_args = array(
        'show_ui' => true,
        'public' => true,
        'taxonomies' => array(
            'product_category'
        ),
        'supports' => array(
            'title',
            'editor',
            'thumbnail',
            'slug'
        ),
        'labels' => array(
            'name' => 'Products',
            'singular_name' => 'Product',
            'add_new' => 'Add New Product',
            'add_new_item' => 'Add New Product',
            'edit_item' => 'Edit Product',
            'new_item' => 'New Product',
            'view_item' => 'View Product',
            'search_items' => 'Search Products',
            'not_found' => 'No Products Found',
            'not_found_in_trash' => 'No Products Found In Trash'
        ),
        'capability_type' => 'page',
        'rewrite' => array( 'slug' => 'produkt' )
    );

    register_post_type( 'product', $box_post_type_args );

    // Add new taxonomy, make it hierarchical (like categories)
    $labels = array(
        'name' => _x( 'Categories', 'taxonomy general name' ),
        'singular_name' => _x( 'Category', 'taxonomy singular name' ),
        'search_items' =>  __( 'Search Category' ),
        'all_items' => __( 'All Categories' ),
        'parent_item' => __( 'Parent Category' ),
        'parent_item_colon' => __( 'Parent Category:' ),
        'edit_item' => __( 'Edit Category' ), 
        'update_item' => __( 'Update Category' ),
        'add_new_item' => __( 'Add New Category' ),
        'new_item_name' => __( 'New Genre Category' ),
        'menu_name' => __( 'Categories' ),
    );  

    register_taxonomy( 'product_category', array( 'product' ), array(
        'public' => true,
        'hierarchical' => true,
        'labels' => $labels,
        'show_ui' => true,
        'query_var' => true,
        'rewrite' => array( 'slug' => 'produkter' ),
    ));
}
add_action( 'init', 'product_register_product_post_type');

You need to set up a custom taxonomy and then add the name of the custom tax via the “taxonomies” arg when registering the custom post type.