https://support.mozilla.org/en-US/questions/1356031#answer-1458348
In Activity Manager, when saving a Draft or message to Sent folder, or
moving from a local folder to IMAP:
*"The current operation on 'Drafts' did not succeed. The mail server
for account [email protected] responded: Expected literal, but saw UTF8"*
*Reproducible in any build of Thunderbird 91*, including nightlies
from this week, in Troubleshooting Mode, and even with a completely
new profile. Happens on *Windows and MacOS* - across several OS
releases of both.
It is *not a transport (TLS/SSL) problem*, as other IMAP operations
work (moving, marking, flagging, deleting, etc)
It's not a (user) data problem either, as fresh accounts both client
and server-side manifest this issue.
I am running *ArchiveOpteryx as the mailserver*, but nothing
significant/useful is logged there either, as it's an MUA problem.
Been running Tbird/Mozilla/etc for decades - this is a new Tbird problem.
