I have noticed I have this issue on multiple UI images that have transparency around them. Sometimes you can see a thin, 1 pixel wide, line on some edge of the image.
This is an example, the image with the transparency is the dialog at the bottom, then there’s about 100 pixels with transparency and some shadow. At the end of it, a darker line appears (I added a red rectangle to see it easier), but that line is nowhere in the original texture.
This is the original texture top:
The image is not even scaled in any way.
