Selectively omit post meta (Custom Fields) from being indexed by SearchWP

gistfile1.php

<?php

function my_searchwp_omit_meta_key( $omit, $meta_key, $the_post ) {
	
	// don't index anything marked as private (starts with _)
	if ( '_' == substr( $meta_key, 0, 1 ) ) {
		$omit = true;
	}
	
	return $omit;
}

add_filter( 'searchwp_omit_meta_key', 'my_searchwp_omit_meta_key', 10, 3 );