private function decodeMimeHeader(string $header) : string
{
$headerDecoded = imap_mime_header_decode($header);
// Decode failed
if (false === $headerDecoded) {
return trim($header);
}
$header = '';
for ($i = 0; $i < count($headerDecoded); $i++) {
$header .= $this->convertToUtf8($headerDecoded[$i]->text, $headerDecoded[$i]->charset);
}
return trim($header);
}