Real Fit Width (bug / feature?)

When presenting a Prototype, the option Fit Width doesn’t seem to be working as expected.

When presenting in a bigger display the artboard doesn’t stretch, it doesn’t fit to the width of the screen.

I suppose it is to protect pixel stretching but that is far more less to happen or to be a problem then the usefulness of it working correctly.

I use to work in lower resolutions to save resources (local and server wise). But then when I have to present my work it’s framed on the sides because it doesn’t stretch.

Thank you