User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/106.0.0.0 Safari/537.36

Steps to reproduce:

1.) Doubleclick pdf or jpg in E-Mail -> Error message (see. screenshot)
2.) tryed to store these pdfs or jpgs on harddisk
3.) went to destination folder
4.) files only have 1KB size

Actual results:

File cannot be opened. after doubleclick a message (s. screenshot) appears like: unknown picture format or malformed file
Heres a temporary solution:
1.) Drag E-Mail out from Thunderbird to Desktop
2.) Open E-Mail with doubleclick from Desktop
3.) open pdfs or jpgs with doubleclick in this E-Mail now without problems

Expected results:

Doubleclick should open attachments immediately without draging it out to desktop

1.) problem exists only with some e-mails. please let me know, if i should upload an eml file or source code of an e-mail where the problem exist
2.) problem with this e-mails exist on all Thunderbird-Clients. reinstall or new profile does not solve this problem
3.) and as i wrote:
there is a temporary solution:
1.) Drag E-Mail out from Thunderbird to Desktop
2.) Open E-Mail with doubleclick from Desktop
3.) open pdfs or jpgs with doubleclick in this E-Mail now without problems

An .eml might help yes.
But first, update to Thunderbird 102 and see if you still see the problem

Just upgraded to 102.4.1 -> same problem
I think most e-mail, with this problem was sent by phones. i will load up an eml file

File is too big so here is a link:
https://wetransfer.com/downloads/13aaaf3046b032af3b43e8a14c125c6820221027105253/e5a86b091ac3fc4843e95761a9ff699420221027105325/64eb6a

Additional Information:
if i open the eml file with doubleclick, it works like the temporary solution (as i wrote above)
but when i drag this eml file into thunderbird inbox or another folder, the problem is back and the behavior is the same, when such an e-mail is comming in on regular way with imap

(In reply to a.wass from comment #4)

File is too big so here is a link:
https://wetransfer.com/downloads/13aaaf3046b032af3b43e8a14c125c6820221027105253/e5a86b091ac3fc4843e95761a9ff699420221027105325/64eb6a

The file has not been downloaded yet, so the file will no longer be available on wetransfer as of tomorrow.
Is there another possibility for uploading this eml file (about 26 MB)?

I can click open those attached images just fine.
When you click, is the message in an imap folder?

Yes, the message is in an imap folder

xref/dupe bug 1757478

Testing my clients now with these values and it seems it works:

pref("browser.cache.memory.capacity", 512000);
pref("browser.cache.memory.max_entry_size", -1);

Adding the two entries into prefs works for me. Large (20MB or so) attachments properly transfer.

See also https://bugzilla.mozilla.org/show_bug.cgi?id=1813595 ?

This seems to be working in Daily. Probably fixed by bug 1805186.