Unreal Engine applies the aspect ratio of the viewport to a fixed Horizontal Field of View. Therefore, switching from standard 16:9 to ultrawide will crop the top and bottom of the view and zoom, rather than revealing more to the left and right as you’d expect, and shrinking it to 4:3 creates an extreme fisheye effect.
Unreal Default: content on the sides of the viewport is fixed, causing weird cropping and zooming.
Our Camera: fixing content on the top and bottom of the viewport, like we expect.
The default is basically never what we want, but it’s hard-coded and there’s no way to override it with just configuration, so we have to patch it. 😖