So the easiest way i found is:
$field = get_post_meta( $propostid, '_pf_error_log', true );
$field[] = 'new raw string';
update_post_meta( $propostid, '_pf_error_log', $field );
But i will be happy to get a more simple and elegant solution…
So the easiest way i found is:
$field = get_post_meta( $propostid, '_pf_error_log', true );
$field[] = 'new raw string';
update_post_meta( $propostid, '_pf_error_log', $field );
But i will be happy to get a more simple and elegant solution…