https://www.cnet.com/roadshow/news/hyundai-mobis-self-driving-car-lighting-ces-2019/

The lighting elements are hidden in the body, giving it a nice and seamless look.

When the car comes to a stop, it can display a crosswalk on the ground, signaling it's OK to cross in front of the vehicle. Then, when it comes time to move again, the car's LED boards will show a countdown, while arrows highlight the direction of travel.