Hi,
In case of log out when connecting displays, your system may be mirroring. This is not yet supported in High Sierra.
In some cases (for example VGA screens or projectors) this is the default behaviour so there is no workaround yet.
However in many cases it's possible to remove a saved layout by following the instructions in
http://support.displaylink.com/knowl...ticles/1812676
Let me know if this works for you.
Regards,
Carlo