Unity terrain grass waving tint has borders on adjucent terrain tiles

I am experimenting with standard Unity terrain grass, waving parameters in particular. The terrains are organized in adjucent tiles and heighbourship is set between tiles using Terrain.SetNeighbors. However, wavingGrassTint (set to red for tests) produces hard boders between terrain tiles. It's an interesting feature to simulate strong wing, but with such borders I will not be able to use it. Is it possible to fix this?

 

Did you find a solution to this?
I've been having exactly the same problem for a very long time across different versions of unity.