Today I have exported an UV Layout from Blender 2.8 and imported in Photoshop in order to build a simple displacement map. After have imported the UV MAP I noticed, that all the UV lines are not black but a kind of black to grey graduation! The lines are not 1 pixel wide but 2 or three! I have tried every settings I can do in the Export UV panel but I got always the same.
Here you find the original UV layout in Blender 2.8:
And here you will find the snapshot out of Photoshop with the strange grayish lines:
BTW, I have the same issue editing the same file in GIMP or other graphic programs. So it seems that the Blender 2.8 exporter is creating this behavior.
Many thanks for a hint!