WP_REST_URL_Details_Controller::get_icon( string $html, string $url ): string

308	private function get_icon( $html, $url ) {309		// Grab the icon's link element.310		$pattern = '#<link\s[^>]*rel=(?:[\"\']??)\s*(?:icon|shortcut icon|icon shortcut)\s*(?:[\"\']??)[^>]*\/?>#isU';311		preg_match( $pattern, $html, $element );312		if ( empty( $element[0] ) || ! is_string( $element[0] ) ) {313			return '';314		}315		$element = trim( $element[0] );316 317		// Get the icon's href value.318		$pattern = '#href=([\"\']??)([^\" >]*?)\\1[^>]*#isU';319		preg_match( $pattern, $element, $icon );320		if ( empty( $icon[2] ) || ! is_string( $icon[2] ) ) {321			return '';322		}323		$icon = trim( $icon[2] );324 325		// If the icon is a data URL, return it.326		$parsed_icon = parse_url( $icon );327		if ( isset( $parsed_icon['scheme'] ) && 'data' === $parsed_icon['scheme'] ) {328			return $icon;329		}330 331		// Attempt to convert relative URLs to absolute.332		if ( ! is_string( $url ) || '' === $url ) {333			return $icon;334		}335		$parsed_url = parse_url( $url );336		if ( isset( $parsed_url['scheme'] ) && isset( $parsed_url['host'] ) ) {337			$root_url = $parsed_url['scheme'] . '://' . $parsed_url['host'] . '/';338			$icon     = WP_Http::make_absolute_url( $icon, $root_url );339		}340 341		return $icon;342	}