Terrain in 2018.3.5 , (Standard material) gfx bug

Hello couple of days ago i posted this exact issue on answers but no answer came so i'll try it here again

i recently ported over my game to the latest stable 2018.3.5 and when painting recommenced on the terrains i got some weird lighting issues around the edges of texture interpolations.

Take a look at the image:


With just only using albedo channels and nothing else:



+ using the standard built in material (the new one no deprecated ones) and no lightmapping enabled and such just a basic scene with one terrain and a directional light.

There's nothing much i can do because it's all built in stuff ....

any ideas ?

Thanx in advance

 

Bump.

I seriously can't be the only one that has this problem ?.
The same terrains used before 2018.3.5 worked perfectly , and when i port it to then newest unity version it produces this , surely it is a bug.