samba - Mar 2017 - Windows 10 clients don't close session connections on reboot or log off

Hi!

We are using Samba 4.3.11 as an Active Directory Domain Controller with Windows
10 clients and a mix of
folder redirection (AppData/Roaming, Documents, Pictures, Desktop ...) and
profiles.

In most cases the smb connections are not closed when a user restarts the
computer or simple do a log off.
If i run "smbstatus | grep username" on the server i see many open
files, especially the Mozilla Firefox profile, desktop.ini
and other, although the computer is powered off, or the user logged off.
Because of this, when a user restarts his computer, or login again it takes a
long time until he see his Desktop and Firefox
don't start anymore and tells the user that it is already running. I must
kill all connections manually on the server, to get
it work again.

Is there any solution out there to fix this problem? Any smb.conf option that
will force closing connections on log off,
or something like that?

Thanks for help!

Julian