I'm running Ubuntu 16.04 using a dual monitor setup.
Every once in a while I update my system via apt-get update
followed by apt-get upgrade
.
After reboot the first monitor is duplicated to the second one. When I go to System settings -> Display and monitor
and I click on the info button both displays show the same input source (HDMI), which is obviously wrong.
Any ideas on how to resolve this problem?