here is how mb_ucfirst should be implemented in userland
<?php
function mb_ucfirst(string $str, string $encoding = null): string
{
if ($encoding === null) {
$encoding = mb_internal_encoding();
}
return mb_strtoupper(mb_substr($str, 0, 1, $encoding), $encoding) . mb_substr($str, 1, null, $encoding);
}
?>
(when i wrote this comment, everybody else's attempt got it wrong for one reason or another, for example: some don't allow you to specify encoding, and some defaulted to utf-8 instead of defaulting to mb_internal_encoding() )
