Another workaround is to switch your primary display from laptop screen to external monitor/TV by moving laptop to the right in display settings, since left screen is always default in Unity. When you do that, you can turn off the laptop screen http://i.imgur.com/ZD8YE.png
Another workaround is to switch your primary display from laptop screen to external monitor/TV by moving laptop to the right in display settings, since left screen is always default in Unity. When you do that, you can turn off the laptop screen http:// i.imgur. com/ZD8YE. png