Mesh Filter Component: "meshname" replaced with "meshname Instance"

At some point the references to the meshes in all of my mesh filters were replaced with the mesh’s name plus “Instance” (i.e. “Wooden_Chair” is replaced with “Wooden_Chair Instance”). It has caused several problems, not least of which being that when I reexport a mesh, these instances are not updated.

I’ve had to go through and replace them one by one (I have hundreds of objects at this point).

Can anyone tell me what I did to cause this so I can avoid it in the future?

Thanks!

At a guess, you have a script which has modified the MeshFilter.mesh property, creating a new instance of the mesh at runtime.
You may have intended to modify the MeshFilter.sharedMesh instead, which would not have instanced the mesh.