You want to drive straight ahead. What should you do if the [red] truck immediately drives off on “green”?

In this situation, you are faced with a red truck driving off after the traffic light turns green for you. According to German traffic laws, there are important considerations when navigating such scenarios.

1. **Allowing the Truck to Move Off**: If the truck is already in motion, it's essential to let it pass before you proceed. This ensures safety and prevents potential collisions.

2. **Warning Signal**: If it's necessary due to the situation (e.g., if the truck might not see you), giving a warning signal can help communicate your intentions to avoid confusion and ensure safe navigation through the intersection.

Driving off immediately when another vehicle is in motion can lead to dangerous situations, so it's crucial to follow the rule of yielding to larger vehicles that require more time and space to maneuver. Following this approach supports overall traffic safety and compliance with road regulations.