While doing some unethical experiments on helpless trains i noticed that wagon collision boxes don't match up with the wagon graphic after a 360° turn. The collision box is about 1 tile too low (or the graphic too high). The yellow lines indicate the wagon collision box, and you can also see that on the left bottom an inserter is grabbing from "in-between" two wagons.
Thanks for the report however this is working correctly. The train renders the individual rolling stocks offset from the actual bounding box on purpose to make the rendering work correctly.
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