Thunderbird snap unable to send or save messages with custom download dir location

[A]

Package: thunderbird
Version: 2:1snap1-0ubuntu3

I have KDE with custom downloads folder location (/mnt/M.2/Downloads in my case), and when I try to send or save message I have msg box with "error sending message"

In `journalctl -f` there is following message

kernel: audit: type=1400 audit(1715558212.734:570): apparmor="DENIED" operation="mkdir" class="file" profile="snap.thunderbird.thunderbird" name="/mnt/M.2/Downloads/thunderbird.tmp/" pid=52900 comm="thunderbird-bin" requested_mask="c" denied_mask="c" fsuid=1000 ouid=1000

[Sebastien Bacher (seb128)]

Thank you for your bug report. Is that directory an actual mount from another location? That's more of a snapd question

[A (zorn-v)]

Yep, it is another physical device

/dev/sda2 46G 12G 32G 28% /
/dev/nvme0n1p1 938G 672G 220G 76% /mnt/M.2

[A (zorn-v)]

> That's more of a snapd question

Why thunderbird (snap version) save own temp files in "downloads" at all ?

[Jora Sucharik (c3374610)]

> Why thunderbird (snap version) save own temp files in "downloads" at all ?
Snapcraft's people choice.

As thunderbird is packaged as snap and with default settings, it's unusable. I ran into the same problems - you can't send a mail neither save it as draft.

[Jora Sucharik (c3374610)]

Snapcraft's people suggested a workaround:

sudo snap connect thunderbird:removable-media

[A (zorn-v)]

> Snapcraft's people suggested a workaround

Thanks

[Brice Terzaghi (terzag)]

Upgraded to Xubuntu 24.04 a few days ago, so got Thunderbird switched to a snap. Today, I've had an e-mail to send for the first time and got an error message saying it can't send it.

In journalctl, I have the following:

kernel: audit: type=1400 audit(1717598347.884:296): apparmor="DENIED" operation="mkdir" class="file" profile="snap.thunderbird.thunderbird" name=2F6D6E742F64617461322F54C3A96CC3A96368617267656D656E74732F7468756E646572626972642E746D702F pid=31351 comm="thunderbird-bin" requested_mask="c" denied_mask="c" fsuid=1000 ouid=1000

Unlike OP, I don't seem to have a mount point mentioned in "name". But while my Downloads dir is not set elsewhere through the DE, it is actually a symlink from my home dir to a different partition on a secondary hard drive.

Connecting the snap to removable-media as suggested seems to fix the issue. Maybe this should be set by default? or use a different dir than $HOME/Downloads for temporary files?