Offending commit: 6ca637b

Ok. I will fix this one. It is an easy one. Tomorrow you'll have your fix.

I had forbid 90 deg for opf rejected, which was doing it the right way :/
#7070

But just to let you know...
I've been trying to develop new features for water transport. OPF just tries to "guess" a path and fails too many times.
I would like to see it removed. It is not good at pathfinding, not only because of 90 deg turns. It is obsolete and in my opinion any second trying to improve it is a wasted second.

The other thing is why 90 deg setting isn't separated into two settings, one for ships and another for trains.

Regarding the last thing, when I was going to do that originally all feedback said just remove it for ships.

Indeed "forbid 90°" only matters for trains. Ships can turn on spot.

I am trying to develop water features and one of them is making ships avoiding rotation (I like the rotation feature, but I also try to make water routes more interesting for gameplay purposes). That is why I ask to keep this setting for ships.
If there is no intention on improving water transport (as making ships crossing over each other), it can be removed from master.