Thunderbird issues with read status

[Mark Berndt]

On Fri, 23 Jun 2017 10:52:06 PM Stefan Froehlich wrote:
> Thunderbird client seems to not updating the read status properly. When
> an email is marked as read or unread it doesn't sync through to
> roundcube webmail or active sync clients nor to another thunderbird
> instance on another computer. Pressing F5 in Thunderbird reverts the change.
> 
> Marking an email in Roundcube or on an active sync device works fine and
> the changes are synced to the Thunderbird clients as well.
> 
> This was working before and started only recently but I cannot tell
> after which update it started.
> 
> Debian 8, Kolab 16
> 
> Any idea where to look at?


I'm seeing this too on a centos install.  It appeared after the last set of 
updates 2 or 3 days ago.