Setup Dual monitor.

I mainly use a laptop, also I used to use a desktop PC. so I have a monitor but I haven't used it for a year because dual monitor need enough space to put the monitor :( However, I update my laptop today, and noticed gnome-desktop package was updated, and this update has a bug fix which is related to a monitor. so, I setup dual monitor environment. actually, I sometimes wanted to have dual monitor system by the way.
This setup was really easy as I thought. When I plugged a monitor's cable to the laptop, Fedora automatically detects external monitor.

Then I have dual monitor system.

Also, I surprised about screensaver. It shows different picture for each monitor.

That looks good :)