Yet another effect of same bug: Frontend mupdate cannot retrieve mailboxes from Master. Server side logs show "LOGOUT" before the end of list: note interruption before the end of "Archive" word.
....
zzz lrswipkxtecda storage 01
U01 MAILBOX {21+}
user.zzz.Arch<1718371746<Q01 LOGOUT
client side logs permanent repeats:
Jun 16 06:10:06 bha-imap cyrus/mupdate[1330156]: successful mupdate connection to XXXX Jun 16 06:10:06 bha-imap cyrus/mupdate[1330156]: scarfing mailbox list from master mupdate server Jun 16 06:10:06 bha-imap cyrus/mupdate[1330156]: retrying connection to mupdate server in 24 seconds
Yes, the mentioned LIST issue in ctl_mboxlist -m is also present.
Debian Stable, Cyrus 3.6.1-4+deb12u2. Downgrade to 3.6.1-4+deb12u1 solves both problems.
