Overtaking ban with addition “Trecker may be overtaken”

This morning I once again had a tractor in front of me. On the federal road there was a ban on overtaking, with the additional sign that tractors can be overtaken. Then the following question went through my mind: What if a car driving directly behind the tractor does not dare, or belongs to the tractor driver and therefore does not want to overtake it? Can I overtake it anyway? Or would I commit a overtake by overtaking the following car? bring the dark??