How to rotate and keep full video width and height?

I looked all over, no answer did I find.
Why does shotcut turn my widescreen video into a cube, after rotating it? This is rather goofy.
Is there a way to keep the whole thing?"

Are you trying to make a vertical video?

180 degree turn to keep the same aspect ratio

No, making a vertical into a landscape, sorry, wasn’t clear. 90 degree rotation.

With no specifications, I made my own up.
Video Mode 1080p (1920x1080)

Shotcut 19.07.15

The “Proper” step is to set the appropriate Resolution.
shotcut_2019-08-17_04-01-40

Even if you ignore it, the steps I shown above still work if left in Automatic.
If you want to save it, just push Ctrl + S just once.