Noticing slight choppiness at the edges of custom skybox textures

[[FP] OBV10U3_NINJA]

I've exported a skybox texture from SpaceEngine and put it in a test map, and for the most part it's perfect, but the only downside is that despite the fact they are seamless if lined up in an external software, the texture looks as though it's scaled up by something like 1.001x (wild guess), because it looks as though the very edges of the texture are chopped off. I've tested with both 1024^2 textures as well as 2048^2 ones, and I've tried both with and without generating mipmaps, but nothing happens. Anyone got any idea why this is occurring? It hasn't happened before and idk what I started doing different.

 

[Pocket]

Did you remember to enable S and T clamping?

 

[[FP] OBV10U3_NINJA]

Yes I did, in fact. I expected that to work but it didn't.