On 28/12/16 17:02, Niels Thykier wrote:
Note the difference between "=?UTF-8?Q?" vs. "=?UTF-8?b?" (Q vs. b). I presume the "b" is for "binary" or/and "Base64 encoded" vs. Q which would be "quoted printed" or something like that. I am not an expert on permitted ways of quoting UTF-8 in mail headers, but the base64 method does not seem entirely inconceivable for some RFC to support that (especially not considering you can encode the body with base64).
Nor am I, the experts wrote the MIME RFC [1]. Which basically says that both encodings are allowed, but the Q (Quoted printable) is actually recommended in a case like this.
Cheers! --alec [1] https://www.ietf.org/rfc/rfc2047.txt, section 4,