White fringe on edges of some objects/textures

[Ostentatio 1,970]

I'm not sure if this is an ambient occlusion issue or what, but on the edges of some graphics, there's a sort of white fringe between the object and whatever is in the background.

 

Sometimes it's more or less apparently, but it's pretty common. Screenshots below with various examples circled.

 

These images are full-resolution PNG because I didn't want JPEG compression artifacts to become a factor, so I'm going to link most of them instead of embedding.

 

https://www.dreamsleeve.org/img/wurm/fringe/fringe1.png

https://www.dreamsleeve.org/img/wurm/fringe/fringe2.png

https://www.dreamsleeve.org/img/wurm/fringe/fringe3.png

https://www.dreamsleeve.org/img/wurm/fringe/fringe4.png

 

Sample:

 

It's almost like objects have a fringe that isn't necessarily "white" per se, but nullifies shadows? I'm not sure.