able form fields if called from the Gutenberg editor.
	 *
	 * @since 1.7.5
	 *
	 * @return void
	 */
	private function disable_fields_in_gb_editor() { // phpcs:ignore WPForms.PHP.HooksMethod.InvalidPlaceForAddingHooks

		add_filter(
			'wpforms_frontend_container_class',
			static function ( $classes ) {

				$classes[] = 'wpforms-gutenberg-form-selector';

				return $classes;
			}
		);
		add_action(
			'wpforms_frontend_output',
			static function () {

				echo '<fieldset disabled>';
			},
			3
		);
		add_action(
			'wpforms_frontend_output',
			static function () {

				echo '</fieldset>';
			},
			30
		);
	}

	/**
	 * Output CSS variables for the particular form.
	 *
	 * @since 1.8.1
	 *
	 * @param array $attr Attributes passed by WPForms Gutenberg block.
	 */
	private function output_css_vars( $attr ) {

		if ( empty( $this->css_vars_obj ) || ! method_exists( $this->css_vars_obj, 'get_vars' ) ) {
			return;
		}

		$this->css_vars_obj->output_root();

		if ( $this->render_engine === 'classic' || $this->disable_css_setting !== 1 ) {
			return;
		}

		$css_vars = $this->css_vars_obj->get_customized_css_vars( $attr );

		if ( empty( $css_vars ) ) {
			return;
		}

		$style_id = "#wpforms-css-vars-{$attr['formId']}-block-{$attr['clientId']}";

		/**
		 * Filter the CSS selector for output CSS variables for styling the GB block form.
		 *
		 * @since 1.8.1
		 *
		 * @param string $selector The CSS selector for output CSS variables for styling the GB block form.
		 * @param array  $attr     Attributes passed by WPForms Gutenberg block.
		 * @param array  $css_vars CSS variables data.
		 */
		$vars_selector = apply_filters(
			'wpforms_integrations_gutenberg_form_selector_output_css_vars_selector',
			"#wpforms-{$attr['formId']}.wpforms-block-{$attr['clientId']}",
			$attr,
			$css_vars
		);

		$this->css_vars_obj->output_selector_vars( $vars_selector, $css_vars, $style_id, $this->current_form_id );
	}

	/**
	 * Output custom CSS styles.
	 *
	 * @since 1.8.8
	 *
	 * @param array $attr Attributes passed by WPForms Gutenberg block.
	 */
	private function output_custom_css( $attr ) {

		if ( wpforms_get_render_engine() === 'classic' ) {
			return;
		}

		$custom_css = trim( $attr['customCss'] ?? '' );

		if ( empty( $custom_css ) ) {
			return;
		}

		$style_id = "#wpforms-custom-css-{$attr['formId']}-block-{$attr['clientId']}";

		printf(
			'<style id="%1$s">
				%2$s
			</style>',
			sanitize_key( $style_id ),
 			esc_html( $custom_css )
		);
	}
}
<br />
<b>Fatal error</b>:  Uncaught Error: Class &quot;WPForms\Integrations\Gutenberg\FormSelector&quot; not found in /home/valigeria/public_html/wp-content/plugins/wpforms/src/Pro/Integrations/Gutenberg/FormSelector.php:13
Stack trace:
#0 /home/valigeria/public_html/wp-content/plugins/all-in-one-seo-pack-pro/vendor/composer/ClassLoader.php(576): include()
#1 /home/valigeria/public_html/wp-content/plugins/all-in-one-seo-pack-pro/vendor/composer/ClassLoader.php(427): Composer\Autoload\{closure}('/home/valigeria...')
#2 [internal function]: Composer\Autoload\ClassLoader-&gt;loadClass('WPForms\\Pro\\Int...')
#3 /home/valigeria/public_html/wp-content/plugins/wpforms/src/Integrations/Loader.php(100): class_exists('WPForms\\Pro\\Int...')
#4 /home/valigeria/public_html/wp-content/plugins/wpforms/src/Integrations/Loader.php(57): WPForms\Integrations\Loader-&gt;register_class('Gutenberg\\FormS...')
#5 /home/valigeria/public_html/wp-content/plugins/wpforms/src/Integrations/Loader.php(22): WPForms\Integrations\Loader-&gt;__construct()
#6 /home/valigeria/public_html/wp-includes/class-wp-hook.php(324): WPForms\Integrations\Loader::get_instance('')
#7 /home/valigeria/public_html/wp-includes/class-wp-hook.php(348): WP_Hook-&gt;apply_filters(Object(WPForms\Providers\Providers), Array)
#8 /home/valigeria/public_html/wp-includes/plugin.php(517): WP_Hook-&gt;do_action(Array)
#9 /home/valigeria/public_html/wp-content/plugins/wpforms/src/WPForms.php(277): do_action('wpforms_loaded')
#10 /home/valigeria/public_html/wp-includes/class-wp-hook.php(324): WPForms\WPForms-&gt;objects('')
#11 /home/valigeria/public_html/wp-includes/class-wp-hook.php(348): WP_Hook-&gt;apply_filters(NULL, Array)
#12 /home/valigeria/public_html/wp-includes/plugin.php(517): WP_Hook-&gt;do_action(Array)
#13 /home/valigeria/public_html/wp-settings.php(550): do_action('plugins_loaded')
#14 /home/valigeria/public_html/wp-config.php(111): require_once('/home/valigeria...')
#15 /home/valigeria/public_html/wp-load.php(50): require_once('/home/valigeria...')
#16 /home/valigeria/public_html/wp-blog-header.php(13): require_once('/home/valigeria...')
#17 /home/valigeria/public_html/index.php(17): require('/home/valigeria...')
#18 {main}
  thrown in <b>/home/valigeria/public_html/wp-content/plugins/wpforms/src/Pro/Integrations/Gutenberg/FormSelector.php</b> on line <b>13</b><br />