User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/94.0.4606.81 Safari/537.36

Steps to reproduce:

After an automatic update of v 78.14.0 to 91.2.0 every 5th or 6th email sent by attaching pdf via mapi from a Filemaker database failed with the error message:

'SEND MESSAGE ERROR
Sending of the message failed.
There was an error attaching Email_Attachment.pdf. Please check that you have access to the file.'

Reproduced on several Windows 10 Pro computers with either Windows Defender or Bitdefender Endpoint Security Tools, both 32 and 64 bit versions of Thunderbird, both v 91.0.1 and v 91.2.0 TB installs and both fresh install or updated within Thunderbird.

Actual results:

Every time the sent email failed the temporary attachment file located in the moz_mapi temp folder was removed/deleted before the email was completed (i.e. To: and Subject: filled and send button clicked), causing the error.

Expected results:

Temporary attachment file located in the moz_mapi temp folder should remain there until email is sent and only then removed/deleted, which is what happens ~80% of the time.

nsMsgCompose::CloseWindow may be called multiple times.

Can you help me test by downloading an artifact build from https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/MYYDyHkITr-JPBzqsnFpSg/runs/0/artifacts/public/build/target.zip? It's built on https://treeherder.mozilla.org/jobs?repo=try-comm-central&revision=6031e30657d0f4bb594fd8555fc4ede811c50a56. Thanks

Pushed by mkmelin@iki.fi:
https://hg.mozilla.org/comm-central/rev/c6f878207aa5
Remove temporary attachments in nsMsgCompose dtor. r=mkmelin

(In reply to Ping Chen (:rnons) from comment #2)

Can you help me test by downloading an artifact build from https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/MYYDyHkITr-JPBzqsnFpSg/runs/0/artifacts/public/build/target.zip? It's built on https://treeherder.mozilla.org/jobs?repo=try-comm-central&revision=6031e30657d0f4bb594fd8555fc4ede811c50a56. Thanks

Hello, sorry it took me so long, but I've tested the daily and the same issue occurs. Thanks.

This is only a workaround, the root cause is nsMsgAttachment dtor is not called reliably.

Anje, Walt, fyi

Pushed by geoff@darktrojan.net:
https://hg.mozilla.org/comm-central/rev/7296c1c8bbbf
Do not remove temporary attachments in nsMsgAttachment dtor. r=mkmelin

I have been testing the latest Daily build - 95.0a1 (2021-10-21) (64-bit) - and that does indeed seem to have resolved the issue. Is there any rough timeline to when this bugfix might appear in the production version? Thanks.

Probably a few weeks.

Comment on attachment 9246785 [details]
Bug 1735601 - Do not remove temporary attachments in nsMsgAttachment dtor. r=mkmelin

Request for the two patches in this bug, and the patch in bug 1736258 to make tests pass.
[Approval Request Comment]
Regression caused by (bug #): bug 1710323
User impact if declined: Temporary attachments are lost when trying to send mails.
Testing completed (on c-c, etc.): c-c
Risk to taking this patch (and alternatives if risky): low

Comment on attachment 9246785 [details]
Bug 1735601 - Do not remove temporary attachments in nsMsgAttachment dtor. r=mkmelin

[Triage Comment]
Approved for beta

Thunderbird 94.0b5:
https://hg.mozilla.org/releases/comm-beta/rev/d95dfbe9508b
Thunderbird 94.0b5:
https://hg.mozilla.org/releases/comm-beta/rev/a462c15d7788

The second path (with all of the LazyLogModule stuff) causes build failures on beta, backing out both patches as well as bug 1736258 which is entangled with this bug.

Backout from 94.0b5:
https://hg.mozilla.org/releases/comm-beta/rev/dd9a60fbb281
https://hg.mozilla.org/releases/comm-beta/rev/220869f628c9

Rebased the second patch in this bug to beta. Please import to beta in this order:

1. https://hg.mozilla.org/comm-central/rev/c6f878207aa5
2. https://hg.mozilla.org/comm-central/rev/1fbbcaf72510
3. 1735601-tb94-beta.patch

Comment on attachment 9246785 [details]
Bug 1735601 - Do not remove temporary attachments in nsMsgAttachment dtor. r=mkmelin

This won't be uplifted to beta as the next beta is going to be 95.0b1, next week.
However, the modified patch will be needed for uplifting to Thunderbird 91.

Comment on attachment 9246785 [details]
Bug 1735601 - Do not remove temporary attachments in nsMsgAttachment dtor. r=mkmelin

[Triage Comment]
removing comm-esr91 flag to avoid confusion - please renominate after beta testing of the patch set is complete

[Approval Request Comment]
Rebased to esr91.

Please import in this order:

1. https://hg.mozilla.org/comm-central/rev/c6f878207aa5
2. 1736258-esr91.patch in bug 1736258
3. 1735601-part2-esr91.patch here

Comment on attachment 9249330 [details] [diff] [review]
1735601-part2-esr91.patch

[Triage Comment]
Approved for esr91

Note patch order

Thunderbird 91.3.1:
https://hg.mozilla.org/releases/comm-esr91/rev/4ea9f0e71c8e
https://hg.mozilla.org/releases/comm-esr91/rev/87734d77fc93