_faces ) ) {
			return $html;
		}

		$urls = [];

		foreach ( $font_faces as $font_face ) {
			if ( empty( $font_face['content'] ) ) {
				continue;
			}

			$font_url = $this->extract_first_font( $font_face['content'] );

			/**
			 * Filters font URL with CDN hostname
			 *
			 * @since 3.11.4
			 *
			 * @param type  $url url to be rewritten.
			 */
			$font_url = apply_filters( 'rocket_font_url', $font_url );

			if ( empty( $font_url ) ) {
				continue;
			}

			$urls[] = $font_url;
		}

		if ( empty( $urls ) ) {
			return $html;
		}

		$urls = array_unique( $urls );

		$replace = preg_replace(
			'#</title>#iU',
			'</title>' . $this->preload_links( $urls ),
			$html,
			1
		);

		if ( null === $replace ) {
			return $html;
		}

		return $replace;
	}

	/**
	 * Remove preconnect tag for google api.
	 *
	 * @param string $html html content.
	 *
	 * @return string
	 */
	protected function remove_google_font_preconnect( string $html ): string {
		$clean_html = $this->hide_comments( $html );
		$clean_html = $this->hide_noscripts( $clean_html );
		$clean_html = $this->hide_scripts( $clean_html );
		$links      = $this->find(
			'<link\s+([^>]+[\s"\'])?rel\s*=\s*[\'"]((preconnect)|(dns-prefetch))[\'"]([^>]+)?\/?>',
			$clean_html,
			'Uis'
		);

		foreach ( $links as $link ) {
			if ( preg_match( '/href=[\'"](https:)?\/\/fonts.googleapis.com\/?[\'"]/', $link[0] ) ) {
				$html = str_replace( $link[0], '', $html );
			}
		}

		return $html;
	}

	/**
	 * Extracts the first font URL from the font-face declaration
	 *
	 * Skips .eot fonts if it exists
	 *
	 * @since 3.11
	 *
	 * @param string $font_face Font-face declaration content.
	 *
	 * @return string
	 */
	private function extract_first_font( string $font_face ): string {
		if ( ! preg_match_all( '/src:\s*(?<urls>[^;}]*)/is', $font_face, $sources, PREG_SET_ORDER ) ) {
			return '';
		}

		foreach ( $sources as $src ) {
			if ( empty( $src['urls'] ) ) {
				continue;
			}

			$urls = explode( ',', $src['urls'] );

			foreach ( $urls as $url ) {
				if ( false !== strpos( $url, '.eot' ) ) {
					continue;
				}

				if ( ! preg_match( '/url\(\s*[\'"]?(?<url>[^\'")]+)[\'"]?\)/is', $url, $matches ) ) {
					continue;
				}

				return trim( $matches['url'] );
			}
		}

		return '';
	}

	/**
	 * Converts an array of URLs to preload link tags
	 *
	 * @param array $urls An array of URLs.
	 *
	 * @return string
	 */
	private function preload_links( array $urls ): string {
		$links = '';

		foreach ( $urls as $url ) {
			$links .= '<link rel="preload" as="font" href="' . esc_url( $url ) . '" crossorigin>';
		}

		return $links;
	}

	/**
	 * Set Rucss inline attr exclusions
	 *
	 *  @return void
	 */
	private function set_inline_exclusions_lists() {
		$wpr_dynamic_lists               = $this->data_manager->get_lists();
		$this->inline_atts_exclusions    = isset( $wpr_dynamic_lists->rucss_inline_atts_exclusions ) ? $wpr_dynamic_lists->rucss_inline_atts_exclusions : [];
		$this->inline_content_exclusions = isset( $wpr_dynamic_lists->rucss_inline_content_exclusions ) ? $wpr_dynamic_lists->rucss_inline_content_exclusions : [];

	}

	/**
	 * Displays a notice if the used CSS folder is not writable
	 *
	 * @since 3.11.4
	 *
	 * @return void
	 */
	public function notice_write_permissions() {
		if ( ! current_user_can( 'rocket_manage_options' ) ) {
			return;
		}

		if ( ! $this->is_enabled() ) {
			return;
		}

		if ( $this->filesystem->is_writable_folder() ) {
			return;
		}

		$message = rocket_notice_writing_permissions( trim( str_replace( rocket_get_constant( 'ABSPATH', '' ), '', rocket_get_constant( 'WP_ROCKET_USED_CSS_PATH', '' ) ), '/' ) );

		rocket_notice_html(
			[
				'status'      => 'error',
				'dismissible' => '',
				'message'     => $message,
			]
		);
	}

	/**
	 * Validate the items in array to be strings only and preg_quote them.
	 *
	 * @param array $items Array to be validated and quoted.
	 *
	 * @return array|string[]
	 */
	private function validate_array_and_quote( array $items ) {
		$items_array = array_filter( $items, 'is_string' );

		return array_map(
			static function ( $item ) {
				return preg_quote( $item, '/' );
			},
			$items_array
		);
	}
}