Why does this base game hair have weird seam lines?

Hi. When you zoom out, the game has to render more objects. To make it easier, it shrinks textures and changes lods.

When this happens, some eras of uvs start to display areas of the texture that have nothing on them. So to fix this issue, you need to fill these areas with something.
Open the diffuse in the image editing program, sample the darkest shade of brown, fill the area meant for hair, move this layer behind the hair texture.

This may not fix it if these uvs are close to borders

add it in the scalp area as well
this is that uv island