File name specification while share via email under linux

[flensrowi]

Hi,

I'm using "Email to..." quite often to send books to Pocketbook E-Readers. this broke for me some time ago. The Pocketbook Sync service replies every time that there was no attachment (which is wrong).
If I send the book to my regular mail address everything seems to be fine. It also works if I use Thunderbird to send the Book.
I'm using Linux nearly all the time but I noticed it works fine if I use Calibre under Windows 11.

So I took a deeper look into the mail(s) Calibre is sending and noticed something odd:

This is the working file name specification from Calibre/Win11:

Content-Type: application/epub+zip
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="Die Bahn - APuZ 8-9/2022.epub"
MIME-Version: 1.0

while it looks different from Calibre/Linux (Manjaro):

Content-Type: application/epub+zip
Content-Transfer-Encoding: base64
Content-Disposition: attachment;
filename*0*=us-ascii''Die%20Eskalation%3A%20Thriller%20%28German% 20Edition;
filename*1*=%29%20-%20Andreas%20Brandhorst.epub
MIME-Version: 1.0

Thunderbird displays both file names as intended but if I use roundcube webmail the file name is displayed as "Part 2" and I guess the Pocketbook service also interprets it the same way.

So the question is how to fix this? I'm using Manjaro Linux and I guess Calibre uses some python function to build an send the mail.
Is there some option within Calibre (guess not) or a way to configure the python module?

[kovidgoyal]

pbsync cant handle non-ascii filenames which is now a fifteen year old standard. The calibre GUI automatically uses ascii filenames when sending to @pbsync addresses, if you use calibre-smtp you are on your own.