apply_filters( 'translation_file_format', string $preferred_format, string $domain )

809	 *810	 * @since 6.5.0811	 *812	 * @param string $preferred_format Preferred file format. Possible values: 'php', 'mo'. Default: 'php'.813	 * @param string $domain           The text domain.814	 */815	$preferred_format = apply_filters( 'translation_file_format', 'php', $domain );816	if ( ! in_array( $preferred_format, array( 'php', 'mo' ), true ) ) {817		$preferred_format = 'php';818	}819 820	$translation_files = array();821