There are some narrow light transparent gaps / cracks at the edges of the airlock room walls on the exterior map, which, depending on current light contidions / sun position cause a shimmer on the edges of the wall detailing and other objects and/or casts spots of light on the ground at along the wall beyond which the sun is on the outside. The gaps themselves are not visible, only the light they let through interacts with the surfaces.
The airlock door model itself also has the same issue, it has a lot of "cracks" that are not visible, but letting light through which then illuminates the floor when the sun is towards the airlock end of the hab (such as the North-East hab in the afternoon).
This is not a new issue, at least the one with the airlock was there for a while now, but now that the airlock room is completely dark in an unpowered hab, it has become very visible.
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