I have the same problem also.
Fresh install. Applied all updates Restarted Enabled Nvidia v180 Driver Configured my Nvidia Quadro card with Twinview Dual monitors Turned on Desktop Effects Now unable to stretch any window across the two monitors.
I have the same problem also.
Fresh install.
Applied all updates
Restarted
Enabled Nvidia v180 Driver
Configured my Nvidia Quadro card with Twinview Dual monitors
Turned on Desktop Effects
Now unable to stretch any window across the two monitors.