public function add_trigger( $trigger = array() ) {
		if ( ! empty( $trigger['id'] ) && ! isset( $this->triggers[ $trigger['id'] ] ) ) {
			$trigger = wp_parse_args(
				$trigger,
				array(
					'id'              => '',
					'name'            => '',
					'modal_title'     => '',
					'settings_column' => '',
					'priority'        => 10,
					'tabs'            => $this->get_tabs(),
					'fields'          => array(),
				)
			);

			if ( empty( $trigger['modal_title'] ) && ! empty( $trigger['name'] ) ) {
				$trigger['modal_title'] = sprintf( _x( '%s Trigger Settings', 'trigger settings modal title', 'popup-maker' ), $trigger['name'] );
			}

			// Here for backward compatibility to merge in labels properly.
			$labels         = $this->get_labels();
			$trigger_labels = isset( $labels[ $trigger['id'] ] ) ? $labels[ $trigger['id'] ] : array();

			if ( ! empty( $trigger_labels ) ) {
				foreach ( $trigger_labels as $key => $value ) {
					if ( empty( $trigger[ $key ] ) ) {
						$trigger[ $key ] = $value;
					}
				}
			}

			// Remove cookie fields.
			if ( ! empty( $trigger['fields']['cookie'] ) ) {
				unset( $trigger['fields']['cookie'] );
			}

			// Add cookie fields for all triggers automatically.
			if ( empty( $trigger['fields']['general']['cookie_name'] ) ) {
				$trigger['fields']['general'] = array_merge( $trigger['fields']['general'], $this->cookie_fields() );
			}

			$this->triggers[ $trigger['id'] ] = apply_filters( 'pum_trigger', $trigger );
		}
	}