public function sanitize_ignored_plugins( $value ) {
		if ( ! function_exists( 'get_plugins' ) ) {
			require_once ABSPATH . 'wp-admin/includes/plugin.php';
		}

		$value = (array) $value;
		$valid_slugs = array_map( function( $file ) {
			if ( false === strpos( $file, '/' ) ) {
				$slug = basename( $file, '.php' );
			} else {
				$slug = dirname( $file );
			}

			return $slug;
		}, array_keys( get_plugins() ) );
		$invalid_slugs = array_diff( $value, $valid_slugs );

		if ( ! empty( $invalid_slugs ) ) {
			add_settings_error(
				'soter_ignored_plugins',
				'invalid_soter_ignored_plugins',
				sprintf(
					'Only currently installed plugins can be ignored. The following invalid plugin slugs were provided: %s',
					implode( ', ', array_map( 'esc_html', $invalid_slugs ) )
				)
			);

			return $this->ignored_plugins;
		}

		return $value;
	}