Which traffic light do I have to follow?
I received an answer from the traffic guidance department of the city. They told that I can either ride on the car lane (left) and then use the regular car traffic lane. If I take the bus lane (right), I do not have to stop at any light at all.

There is no cycle traffic light on the right post because cyclists on the car lane then might interpret that as their light for the left lane as well and get in conflict with a bus on the bus lane.