368905 - When last mime part(s) of multipart/alternative message is/are missing, fall back to showing previous parts (e.g. plaintext)

Status: NEW

(Thunderbird :: Mail Window Front End, enhancement)

Description

[(not reading, please use [e-mail] instead)]

message not displayed

I've got a "safe" reproducable test case from cbeards message.

chris, what mailer did you use?

Comment 1

[(not reading, please use [e-mail] instead)]

Attachment: .eml test case

Comment 2

[(not reading, please use [e-mail] instead)]

Attachment: screen shot of how that eml message looks in tbird

Comment 3

[David :Bienvenu]

that message is corrupt - the image is not present in the message source that the imap server sees;

And it's multipart alternative, but the second part is the missing image

Comment 4

[Myk Melez [:myk] [@mykmelez]]

This looks like a mailer bug, not a Thunderbird bug, but perhaps there's still something Thunderbird can do better to handle situations like these.

It looks like Thunderbird chose to display the image part of a two-part message sent as multipart/alternative, which is probably the right thing to do, as someone who goes to the trouble to create an image alternative probably considers it preferable to the text version of it.

But in this case the image was missing.  Can we make Thunderbird detect that?  If so, we could have it fall back to the text version of the message, as Zimbra appears to be doing.

Comment 5

[David :Bienvenu]

technically, we're displaying the last alternative part, which we're supposed to do, since it's supposed to be the richest part, according to the MIME spec. It doesn't really have to do with that last part being an image. 

I don't know how hard it would be to detect that the image is missing/corrupt, and fall back. That discovery is probably asynchronous, but maybe we do get an error...

Comment 6

[Mike Cowperthwaite]

xref bug 279907.