a common misconception: per german traffic law flashing lights is a valid way to notify the car in front of you of your intent to overtake. of-course does not apply when both cars are in leftmost lane, there it is a punishable offence (drängeln)
a silly law if you ask me. pressuring people driving in front is extremely dangerous. it’s already clear that there is an intention to overtake since you are driving on the outermost lane, no need to be rude and agressive.
