When the From: field contains an umlaut (“ö”), such as:
Andreas Rönnquist <redacted>
it then gets encoded for transport and the literal
text is:
From: Andreas =?UTF-8?B?UsO2bm5xdWlzdA==?= <redacted>
Neomutt properly treats that UTF-8 encoding. However, the 33mail.com
forwarding service apparently re-encodes it in ANSI as follows:
From: "=?ANSI_X3.4-1968?Q?Andreas_R=3Fnnquist?= 'redacted' via 33Mail"
<sen...@mailer1.33mail.com>
This is a bug in the software than generated this header, not in
Neomutt:
• ANSI_X3.4-1968 is an alias for US-ASCII, a 7-bit charset that doesn't
include the character "ö".
• An encoded-word is not allowed inside quoted-string; see RFC 2047 §5.
--
Jakub Wilk
