OTHER VERSION Camera not working in Teams

Because of Coronavirus I have to work in home-office. To be able to have meetings, I had to install Teams (formerly Skype).

Anything works in Teams, except of the camera. The camera works in any other application (Cheese, Guvcview, VLC, ...)

I already tried preloading v4l1compat.so and v4l2convert.so:

I also tried to install Teams with snap and connect the camera:

I suspect that I have to give Teams permission to access the camera somehow. Can anyone give me a hint to solve this problem?