Since IMAP-js is default, my MoCo email does not display anymore the Messages envoyés (Sent messages) sub-folder of [Gmail].

JS Console shows:

no parentRow for  imap://alissy%40mozilla.com@imap.gmail.com/[Gmail] imap://alissy%40mozilla.com@imap.gmail.com/[Gmail]/Messages envoy&AOk-s about3Pane.js:510:19
    addFolder chrome://messenger/content/about3Pane.js:510
    _forAllActiveModes chrome://messenger/content/about3Pane.js:1041
    addFolder chrome://messenger/content/about3Pane.js:1060
    onFolderAdded chrome://messenger/content/about3Pane.js:3032
    possibleImapMailbox resource:///modules/ImapIncomingServer.jsm:389
    handleListResponse resource:///modules/ImapClient.jsm:206
    _nextAction resource:///modules/ImapClient.jsm:216
    _onData resource:///modules/ImapClient.jsm:897
TypeError: can't access property "classList", row is undefined
    expandRow chrome://messenger/content/tree-listbox.js:521
    addFolder chrome://messenger/content/about3Pane.js:512
    _forAllActiveModes chrome://messenger/content/about3Pane.js:1041
    addFolder chrome://messenger/content/about3Pane.js:1060
    onFolderAdded chrome://messenger/content/about3Pane.js:3032
    possibleImapMailbox resource:///modules/ImapIncomingServer.jsm:389
    handleListResponse resource:///modules/ImapClient.jsm:206
    _nextAction resource:///modules/ImapClient.jsm:216
    _onData resource:///modules/ImapClient.jsm:897

The folder is properly subscribed to. If I try to subscribe others under [Gmail] I can see the same errors and they are missing as well.

I dont know if it's related to this specific issue, but I am also seeing errors of bug 1818380 as well as bug 1818945.

Also, on each restart of Thunderbird, I can see in the status bar downloading message xx of yy in Sent messages

Is it a localized (fr) build? Seems to work for me in en build.

OK, I see the problem now, will work on a fix.

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

Is it a localized (fr) build? Seems to work for me in en build.

Yes, french localized build.

(In reply to Ping Chen (:rnons) from comment #3)

OK, I see the problem now, will work on a fix.

Thanks!

has a fix landed yet? with 20230301104821 i see the folder again

Not yet, the fix is in bug 1818676, will duplicate to it later.

The folder disappears when changing between imap-cpp and imap-js, because the physical mailbox name (and .msf file) is encoded differently.
It may happen even after bug 1818676 if the .msf is in some strange state, I had to remove the .msf file manually to get it working during development.

(In reply to Ping Chen (:rnons) from comment #6)

Not yet, the fix is in bug 1818676, will duplicate to it later.

Right

The folder disappears when changing between imap-cpp and imap-js, because the physical mailbox name (and .msf file) is encoded differently.
It may happen even after bug 1818676 if the .msf is in some strange state, I had to remove the .msf file manually to get it working during development.

Could I have been lucky and some other fix landed and made the .msf to somehow be reconstructed?

$ ll ~/.mozilla-thunderbird/2rhz5rws.default/ImapMail/mail.mozilla.com/\[Gmail].sbd/*.msf
-rw-rw-r-- 1 alex alex 3,5K mars   2 10:14 '/home/alex/.mozilla-thunderbird/2rhz5rws.default/ImapMail/mail.mozilla.com/[Gmail].sbd/Brouillons.msf'
-rw-rw-r-- 1 alex alex 1,6K févr. 28 01:39 '/home/alex/.mozilla-thunderbird/2rhz5rws.default/ImapMail/mail.mozilla.com/[Gmail].sbd/Corbeille.msf'
-rw-rw-r-- 1 alex alex 5,2M mars   1 23:16 '/home/alex/.mozilla-thunderbird/2rhz5rws.default/ImapMail/mail.mozilla.com/[Gmail].sbd/Messages envoy&AOk-s.msf'
-rw-rw-r-- 1 alex alex 1,2K févr.  6 22:40 '/home/alex/.mozilla-thunderbird/2rhz5rws.default/ImapMail/mail.mozilla.com/[Gmail].sbd/Messages envoyés.msf'
-rw-rw-r-- 1 alex alex 8,4K mars   2 10:15 '/home/alex/.mozilla-thunderbird/2rhz5rws.default/ImapMail/mail.mozilla.com/[Gmail].sbd/Spam.msf'

I think .msf is reconstructed after reboot. Also imap-js is disabled now, see bug 1820000.

Applied update, I'm on 20230302101845 and the folder disappeared again.

And now it's back and have not disappeared since