How to add your new post type to WordPress category and tag archives

function my_cptui_add_post_types_to_archives( $query ) {
    // We do not want unintended consequences.
    if ( is_admin() || ! $query->is_main_query() ) {
        return;    
    }

    if ( is_category() || is_tag() && empty( $query->query_vars['suppress_filters'] ) ) {
        $cptui_post_types = cptui_get_post_type_slugs();

        $query->set(
            'post_type',
            array_merge(
                array( 'post' ),
                $cptui_post_types
            )
        );
    }
}
add_filter( 'pre_get_posts', 'my_cptui_add_post_types_to_archives' );