The aspect ratio of Tatuus F4 side view mirrors is different from the rear view mirror on a ultra wide monitor. The cars are shown taller and narrower than the same car in the rear view mirror. I don't know if this is intentional or not but it is distracting. This is the only car I frequently drive that has good access to the side view mirrors so I don't know if this a car specific problem.
I believe it is a known bug when using the virtual rear-view mirror, as that changes the aspect ratio of all mirrors.