WordPress filter to replace the default "_" (underscore) with "-" (hyphen) in protected custom fields for debugging purposes

wp-unprotected-meta.php

<?php
/**
 * Replace the default "_" (underscore) with "-" (hyphen) in protected custom fields for debugging purposes
 * 
 * @param bool $protected The default value
 * @param string $meta_key The meta key
 * @return bool True for meta keys starting with "-" (hyphen), false otherwise
 */
function unprotected_meta( $protected, $meta_key ) {

  $protected = ( '-' == $meta_key[0] );
	
	return $protected;
	
}

add_filter( 'is_protected_meta', 'unprotected_meta', 10, 2 );
?>