BUG: sieve does not set seen-Flag

[Ralph Seichter]

* Jakobus Schürz:

> The \Recent flag ist set and the \Seen-Flag is removed in the new
> folder. So it is not a problem of thunderbird.

Did you mention your data storage format yet? If you use Maildir, Flags
are stored as part of the physical file name. For example, the name
"1539996635.M698476P4944.foo,S=45171,W=45803:2,RS" indicates that the
message was seen ('S') and has been replied to ('R'). Check if the file
names match what you see in your MUA.

Files named "dovecot-keywords" are used to map additional letters to
flags (used to store Thunderbird's "$label1" etc.). If the keywords file
get messed up, it can cause confusion, and because there can be keywords
files with varying content per folder, letters in file names can have
different meanings in different directories. Moving files around can be
therefore be tricky.

Also, I wonder if the delivery mechanism might matter. I use Dovecot's
LMTP.

-Ralph