Re: Problem email client iPhone ios18.2
Timo confirmed this type of message (see below) breaks iOS mail clients regardless of the IMAP server used. So it is almost certainly a client issue.
We are in contact with the Apple Mail developers and have provided this debug information to them.
michael
On 02/10/2025 7:19 AM MST Timo Sirainen via dovecot <dovecot@dovecot.org> wrote:
On 10. Feb 2025, at 15.24, Florian Effenberger via dovecot <dovecot@dovecot.org> wrote:
Hello,
frido--- via dovecot wrote on 10.02.25 at 14:07:
The problem as described at the start of this thread is not solved in iOS 18.3. A bit more testing shows that it only appears to happen with attachments around 1MB and bigger.
there seem to be two kind of problems, at least on my devices.
I'm also wondering if there are multiple issues. I have one way of easily reproducing, but it has nothing to do with IMAP IDLE. Here's a test email which causes the hang - snipped it a bit in the middle which you can fill out yourself with:
dd if=/dev/urandom bs=1024 count=3432 | base64 -w76
If you want to test multiple times, change Message-Id for every delivery. This mail can be simply saved to INBOX, e.g. with doveadm save:
To: <user@example.com> Subject: testing Content-Type: multipart/mixed; boundary="foo" Date: Tue, 17 Dec 2024 06:46:17 +0000 From: <user@example.com> Message-Id: <fooab@example.com>
--foo Content-Type: multipart/alternative; boundary="bar"
--bar Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=UTF-8
asdf --bar--
--foo Content-Description: test.pdf Content-Disposition: attachment; filename="test.pdf" Content-Transfer-Encoding: base64 Content-Type: application/octet-stream; name="test.pdf"
lBjZO0luFuyUiOqQ8KPTTpMyPoNhlSTPPJauDuCVSwbZgaNyhnObul5qrdyPKo0NGiQKA3Kha34A <61642 lines of random> 4cNyk39T2wMsnQavfl8LXwG1vNQylpgmSN4p6fOpmGqQ
--foo--
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Hello,
Michael Slusarz via dovecot wrote on 12.02.25 at 19:56:
Timo confirmed this type of message (see below) breaks iOS mail clients regardless of the IMAP server used. So it is almost certainly a client issue.
We are in contact with the Apple Mail developers and have provided this debug information to them.
IIRC, there was also an article from Heise back last year, with several mail providers affected, and the problems started straight away with iOS 18.
Based on Aki's feedback, I tried to do a rawlog of one of the problems (initial connection taking very long, first I see "Connecting.." and then "E-mail download.."), but even with the pre-login log, I could not get any data.
I didn't get to try the test mail from Timo yet.
My gut feeling is that this problem is possibly related to SSL/TLS. I remember Apple changed something with self-signed certificates, so maybe there are some artefacts also with valid (in my case Let's Encrypt) certificates. I played a bit with my SSL settings, to not avail.
Independent of the login issue, I also have the issue that some mails are just not loading, in particular HTML messages, sometimes also certain attachments do not download.
For both problems, I cannot always reproduce them, and I do have the feeling they temporarily get better when I kill the Mail.app.
They are independent from the connection, provider, router etc. Also a direct mobile connection, or IPv4 only, do not fix the issue.
Glad to see work on this is ongoing - thanks so much, I can only guess how tiring it is to fix broken client implementations...
Florian
Op 12-02-2025 om 19:56 schreef Michael Slusarz via dovecot:
We are in contact with the Apple Mail developers and have provided this debug information to them.
Can you tell if there is any progress on this case? We're on iOS 18.4.1 now and the issue still isn't resolved.
-- Regards,
Frido
Op 12-02-2025 om 19:56 schreef Michael Slusarz via dovecot: We are in contact with the Apple Mail developers and have provided this debug information to them. Can you tell if there is any progress on this case? We're on iOS 18.4.1 now and the issue still isn't resolved.
Regards, Frido
Hello,
I was able to look into this a bit more, on two different Dovecot servers (2.3.x on both Debian and FreeBSD).
Deleting the accounts and re-adding them to Mail.app again makes it work for some hours, then all of a sudden stops to work again.
I also experimented with the Mail.app privacy settings and disabled all the features, and then again, for some hours, it seemed to work, from various networks (mobile as well as wifi).
It also seems to work when the phone is connected to the power cable, but I don't know for how long.
While all of that doesn't solve the problem, and I'm not sure if it will be even reproducible, it might help to narrow down the reason (which to me clearly lies within Mail.app).
Florian
participants (3)
-
Florian Effenberger
-
Frido Otten
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Michael Slusarz