506508 - Mail message displays empty when having empty text content => need to display html content

Status: UNCONFIRMED

(MailNews Core :: MIME, defect)

Description

[julien.t43+mozilla]

User-Agent:       Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.2a1pre) Gecko/20090725 Minefield/3.6a1pre
Build Identifier: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; fr; rv:1.9.1b3pre) Gecko/20090223 Thunderbird/3.0b2

having the following text message, i got nothing displayed in message part.
as text content is empty (after removing space-like characters), it would be better to handle it the same way message without text content. in this way, TB would textified html part and display something.

Example:
X-Virus-Scanned: by amavisd-new at usenet-fr.net

--========GMXBoundary178811248126593798244
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit



--========GMXBoundary178811248126593798244
Content-Type: text/html; charset="utf-8"
Content-Transfer-Encoding: quoted-printable

... content ...


Reproducible: Always

Actual Results:  
empty message window

Expected Results:  
text taken from html or other non-empty content

Comment 1

[julien.t43+mozilla]

Attachment: thunderbird test file

Comment 2

[WADA:World Anti-bad-Duping Agency]

> as text content is empty (after removing space-like characters),
> it would be better to handle it the same way message without text content.

First, please read http://en.wikipedia.org/wiki/MIME#Alternative for multipart/alternative.

Bug 348045 is similar request to yours for "no text/plain part in multipart/alternative" case.
> Bug 348045 View Message Body As Plain Text shows blank for multipart/alternative with text/html part only  
Bug 253830 is opposite request to yours.
> Bug 253830 -  "View as plain text" displays HTML part converted to plaintext even though text/plain part is present  

Even if empty text, it's mail sender's intention.
I think automatic text conversion of text/html part is better to be avoided.
I believe enhancement like Bug 495548 (2 in Bug 495548 Comment #5) is a right way to fight with such malformed mail or intentionally malformed spam.

Comment 3

[julien.t43+mozilla]

I agree that thunderbird's behavior is consister with the way way MIME is defined

I disagree about mail sender's intention. Sadly, most of the time it's MUA badly which is programmed.
About solution, as you say, it may not be a good way to change default behavior but an option to consider empty content-part (or when then there is only space-like characters) as non-existent.

Comment 4

[WADA:World Anti-bad-Duping Agency]

(In reply to comment #3)
> Sadly, most of the time it's MUA badly which is programmed.

You receive such malformed but non-spam/non-phishing mail frequently?
I thought many of such mail is spam or phishing mail.
  Target of Spammer/Phisher is users who always display HTML mail in HTML,
  with Display Attachements Inline=Enabled. They don't care for text/plain part
  display by mailer who doesn't support HTML mail. So they don't put text/plain
  part in multipart/alternative or put null text/plain part in
  multipart/alternative. I meant it by "sender's intention".
I agree with you that such mail is generated by bad program they use.

Comment 5

[WADA:World Anti-bad-Duping Agency]

(In reply to comment #3)
> I agree that thunderbird's behavior is consister with the way way MIME is defined

For text/plain part in multipart/alternative, Tb is not so strict, as seen in Bug 253830. And Tb already has some(but not a few) quirks on malformed mail for user's convenience. If many users receive many mail of "mautipart/alternative but no text/plain part" or "mautipart/alternative with  null text/plain part" frequently, I think your request for optional behaviour is reasonable.

Comment 6

[Ludovic Hirlimann [:Usul]]

Removing myslef on all the bugs I'm cced on. Please NI me if you need something on MailNews Core bugs from me.