You are on a road outside of a built-up area, and a car in front of you is driving much slower than is permitted to and has the capacity to. What is the right course of action?

When you encounter a situation where a car in front of you is driving significantly slower than the speed limit and has the ability to drive faster, the appropriate actions are to adjust your speed to that of the slower vehicle and, if safe and permissible, overtake it.

In German traffic regulations, it's important to maintain safe distances and adapt your speed when conditions require it. If the slower vehicle is obstructing traffic, overtaking where it is safe to do so is allowed and often necessary to maintain smooth traffic flow. Flashing your headlights, while sometimes used to signal, is not an appropriate or effective method to compel another driver to speed up and may lead to misunderstandings or aggressive driving behavior.

Thus, the correct combination ensures you comply with safety rules while also respecting the behavior of other drivers on the road.