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From: Magnus Hagander <magnus@hagander.net>
Date: Wed, 7 Jan 2026 21:46:18 +0100
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 <CABUevExfO2oP=h==31c1XM=OsiCc4tbSGZorJ-V3EwAbNaAJBQ@mail.gmail.com>
Subject: Re: Images in news mails
To: Tobias Bussmann <t.bussmann@gmx.net>
Cc: pgsql-www@lists.postgresql.org
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On Thu, 4 Sept 2025 at 21:49, Tobias Bussmann <t.bussmann@gmx.net> wrote:

> Ever since HTML emails were introduced for project news in around 2020, I
> have wondered why, on my system (macOS using Apple Mail as the MUA), emails
> were sometimes displayed in a distorted way. Today, I took the time to
> track it down. Apple Mail ignores the size if the image source is provided
> inline via CID and not referenced externally [2, footnote 3]. As a
> workaround, the width can be specified again in the 'style' tag, as I have
> done in the attached patch.
>
> Another issue is that the Slonik logo is displayed again at the end of the
> email. In contrast to the first issue, this affects the Mail app on iOS as
> well. My analysis suggests that this is caused by the MIME structure of the
> email:
> - multipart/mixed
>   - multipart/alternative
>     - text/plain
>     - text/html
>   - image/png with Content-Disposition: inline
>
> This issue is resolved if I change the structure to the following:
> - multipart/alternative
>   - text/plain
>   - multipart/related
>     - text/html
>     - image/png with Content-Disposition: inline
>
>
Wow, this was a lot of fun. Not.

I have changed the code to restructure like this and it mostly works. It
now breaks in the gmail app on android when connected to our company
emulated-exchange interface. But it fixes apple mail. I think there are a
lot more apple mail out there, so I think it's a strict improvement :)

Thanks for the diagnosing work! I hope this does properly fix it!

//Magnus

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<div dir=3D"ltr"><div dir=3D"ltr"><div dir=3D"ltr"><div dir=3D"ltr"><div di=
r=3D"ltr"><br></div><br><div class=3D"gmail_quote"><div dir=3D"ltr" class=
=3D"gmail_attr">On Thu, 4 Sept 2025 at 21:49, Tobias Bussmann &lt;<a href=
=3D"mailto:t.bussmann@gmx.net" target=3D"_blank">t.bussmann@gmx.net</a>&gt;=
 wrote:<br></div><blockquote class=3D"gmail_quote" style=3D"margin:0px 0px =
0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Ever sin=
ce HTML emails were introduced for project news in around 2020, I have wond=
ered why, on my system (macOS using Apple Mail as the MUA), emails were som=
etimes displayed in a distorted way. Today, I took the time to track it dow=
n. Apple Mail ignores the size if the image source is provided inline via C=
ID and not referenced externally [2, footnote 3]. As a workaround, the widt=
h can be specified again in the &#39;style&#39; tag, as I have done in the =
attached patch.<br>
<br>
Another issue is that the Slonik logo is displayed again at the end of the =
email. In contrast to the first issue, this affects the Mail app on iOS as =
well. My analysis suggests that this is caused by the MIME structure of the=
 email:<br>
- multipart/mixed<br>
=C2=A0 - multipart/alternative<br>
=C2=A0 =C2=A0 - text/plain<br>
=C2=A0 =C2=A0 - text/html<br>
=C2=A0 - image/png with Content-Disposition: inline<br>
<br>
This issue is resolved if I change the structure to the following:<br>
- multipart/alternative<br>
=C2=A0 - text/plain<br>
=C2=A0 - multipart/related<br>
=C2=A0 =C2=A0 - text/html<br>
=C2=A0 =C2=A0 - image/png with Content-Disposition: inline<br>
<br></blockquote><div><br></div><div>Wow, this was a lot of fun. Not.</div>=
<div><br></div><div>I have changed the code to restructure like this and it=
 mostly works. It now breaks in the gmail app on android when connected to =
our company emulated-exchange interface. But it fixes apple mail. I think t=
here are a lot more apple mail out there, so I think it&#39;s a strict impr=
ovement :)</div><div><br></div><div>Thanks for the diagnosing work! I hope =
this does properly fix it!</div><div><br></div><div>//Magnus</div><div><br>=
</div></div><div dir=3D"ltr" class=3D"gmail_signature"><div dir=3D"ltr"></d=
iv></div></div>
</div>
</div>
</div>

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