This happens in 1.11. I haven’t tried 1.12 yet but I don’t see anything about it in the notes. Sometimes my ships will go off the viewable screen; I have only noticed this happening on the bottom.
I noticed that the highlighted area of the map (in the lower left) can be moved so that it touches the left and top sides but it cannot be moved to touch the right or bottom sides. Possibly that has something to do with it?