The problem and the solution are quickly explained.
Think the road has also been created with the 3D-program Blender, but even if not, the problem is the 0-point.
The road, or rather the footpath should not be on the Y-axis 0.000, but 1 mm higher.
But you don't have to change all roads in the 3D editor, you can also solve this directly in the "Road Editor".
Simply set the value "Build Height" from "0" to "0.001" under "Properties" or if it doesn't help then to "0.01".
Demolish the road in the "Road-Editor" and rebuild again, the flickering will disappear.
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