[Mailman-Users] Content filtering and HTML emails. Bug?

[David]

This may be a bug...

Mailman is converting html messages to plain text even when set not to
convert. And it is not an MUA issue. We just verified this using
web-based Gmail on both ends.

Background (from past discussions on this list):

Here is the question:
http://mail.python.org/pipermail/mailman-users/2007-December/059517.html

> Mailman default setting is to converted all HTML to plain text;
> however, our users would like to send out messages with text format.
> We changed the Content Filtering settings to:
> Should Mailman filter the content of list traffic: Yes
> Remove message attachments that don't have a matching content type:
> multipart/mixed, multipart/alternative, text/plain, html
> Should Mailman convert text/html parts to plain text: No
>
> The list still removes the text format even with these settings. Am I
> missing a setting?


Mark Sapiro's answer:
http://mail.python.org/pipermail/mailman-users/2006-April/050753.html

> No. There is nothing you can do in Mailman to do this because it is an
> MUA issue, not a message format issue per se. The same thing should be
> happening if you sent the same message directly to the recipient and
> not through a list.
>
> This is why many people recommend that list mail be plain text only.
> That is a format that all MUAs understand.

We see different (incorrect?) behavior:

To reproduce:

1. Turn content filtering on, but set plain text conversion to NO:

Should Mailman convert text/html parts to plain text: No

2.  Send html emails through the list using web-based gmail on each end.

Expected result:

Receive HTML when an HTML message is sent.

Actual result:

Plain text messages are received. HTML messages are converted to plain
text by Mailman. I believe the next step shows it is not an MUA issue.

Next step:

1. Turn content filtering OFF. No need to make any other changes.

2.  Send html emails through the list using web-based gmail on each end.

Expected result:

Receive HTML when an HTML message is sent.

Actual result:

It works correctly now. HTML messages are not converted to plain text
by Mailman.