How to enable 'projector only' set-up in KDE?

[NikolaZ]

Hi,

I am new to Fedora and Linux in general. I have installed Gnome3, Kde and LXDE to give them all a try.
I preffer KDE by far and would like to use it as my main system.
However, I usually use the laptop connected to a projector, and I turn off the laptop screen to reduce the strain
on the eyes.

I can't seem to get this set up in KDE. I connected to the projector and went to the display menu, but
there was no option to turn off the computer screen, just various ways to arrange two screens at the same time.

Maybe this is a trivial question for some, but it would prevent me from using KDE environment, and I really like it. It's much more functional then Gnome3.

Thanks for any advice.