Oh, I see, thanks Loewchen. I failed to find it. However, are you sure this behaviour is desired? To me it seems most of people who encounter this thing will get confused. After all, what is actually the reason to highlight rails when you place pumps next to them? Especially that these rails don't g...

What I did I tried placing pumps next to fluid wagons and inserters next to cargo wagons. What happened In case of pumps, the yellow rectangle that is supposed to show which fluid tank the pump is going to connect to on the wagon doesn't account for gaps betwen the wagons. In other words, the recta...