public function get_form_class( $provider ) {
		$class = '';

		if ( empty( $provider ) ) {
			/**
			 * Allows filterting the class before returning it in the case of no provider.
			 *
			 * @since 4.10.4
			 *
			 * @param string $class The (empty) class string.
			 */
			return apply_filters( 'tribe_attendee_registration_form_no_provider_class', $class );
		}

		/**
		 * Allow providers to include their own strings/suffixes.
		 *
		 * @since 4.10.4
		 *
		 * @param array $provider_classes in format $provider -> class suffix.
		 */
		$provider_classes = apply_filters( 'tribe_attendee_registration_form_classes', [] );

		if ( array_key_exists( $provider, $provider_classes ) ) {
			$class = 'tribe-block__tickets__item__attendee__fields__form--' . $provider_classes[ $provider ];
		}

		/**
		 * Allows filterting the class before returning it.
		 *
		 * @since 4.10.4
		 *
		 * @param string $class The class string.
		 */
		return apply_filters( 'tribe_attendee_registration_form_class', $class );
	}