Fri, 10 Apr 2026 13:16:54 +0000 https://bugs.horde.org/ticket/12922 PGP: Bad signature for mails with to long lines Hi there, I found a bug in in imp when you try to sign a message with pgp. If I create a Mail with a to long line, imp does not apply automatic line wrapping, but uses format=flowed instead. For such a mail the PGP signature is shown as bad when it is checked with Thunderbird/Enigmail/Gpg4win or with R2Mail2 on Android. Horde itself shows a valid PGP signature. For mails with no long lines (less than 78 characters per line) the signed mails are validated as correct with all clients. Fri, 17 Jan 2014 14:55:50 +0000 https://bugs.horde.org/ticket/12922#t82064 Sounds like a bug in thunderbird. Can verify that the signature is verified as good with the GnuPG4win reference program (Claws Mail) and mutt. Fri, 17 Jan 2014 18:33:56 +0000 https://bugs.horde.org/ticket/12922#t82066 From RFC 3676 (Flowed text RFC; http://tools.ietf.org/html/rfc3676): Therefore, the use of [OpenPGP] with format=flowed messages is strongly discouraged. [OpenPGP-MIME] is recommended instead. We only send messages as OpenPGP-MIME. As per the RFC, there is absolutely nothing wrong with this and is, in fact, explicitly allowed. Looks like Thunderbird is confusing OpenPGP w/ OpenPGP-MIME when dealing with these kind of messages. Wed, 22 Jan 2014 21:23:03 +0000 https://bugs.horde.org/ticket/12922#t82117