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

810	 *811	 * @since 6.5.0812	 *813	 * @param string $preferred_format Preferred file format. Possible values: 'php', 'mo'. Default: 'php'.814	 * @param string $domain           The text domain.815	 */816	$preferred_format = apply_filters( 'translation_file_format', 'php', $domain );817	if ( ! in_array( $preferred_format, array( 'php', 'mo' ), true ) ) {818		$preferred_format = 'php';819	}820 821	$translation_files = array();822