[sylpheed:34856] Can't mark as unread after reply

[uhel at gmx.net]

Hi,

sometimes I mark a message as unread as a reminder even if I already
replied to the message.

The problem is that if I replied, sylpheed shows this little reply
arrow. If the arrow is shown, I can't klick in that column so that the
'unread symbol' is shown again. In that case I need to use the
drop-down menu to get the message marked as unread.
Is this intentional? Bug or feature?

I use v3.1.2 (Build 1120) on Win32

--
regards 
uhel