WP_Widget_Categories::form

		$instance['title']        = sanitize_text_field( $new_instance['title'] );
		$instance['count']        = ! empty( $new_instance['count'] ) ? 1 : 0;
		$instance['hierarchical'] = ! empty( $new_instance['hierarchical'] ) ? 1 : 0;
		$instance['dropdown']     = ! empty( $new_instance['dropdown'] ) ? 1 : 0;

		return $instance;
	}

	/**
	 * Outputs the settings form for the Categories widget.
	 *
	 * @since 2.8.0
	 *
	 * @param array $instance Current settings.
	 */
	public function form( $instance ) {
		// Defaults.
		$instance     = wp_parse_args( (array) $instance, array( 'title' => '' ) );
		$count        = isset( $instance['count'] ) ? (bool) $instance['count'] : false;
		$hierarchical = isset( $instance['hierarchical'] ) ? (bool) $instance['hierarchical'] : false;