Testing out some upgrades to 2019.3a, we are getting some fbx mesh import warnings, along with some missing mesh filter references. Identifier uniqueness violation: 'Name:SurfaceMesh, Type:Mesh'. Multiple Objects with the same name/type are generated by this Importer. There is no guarantee that subsequent imports of this asset will properly re-link to these targets. It seems like the FBX importer cannot handle child nodes with non-unique names. In the model hierarchy for example: Root/ChildA/SurfaceMesh Root/ChildB/SurfaceMesh ^ will give warning for non-unique SurfaceMesh name. I can't seem to find anything in the ModelImporter docs explaining this clearly, or if it's a problem at all (we've had this structure for a long time, but only recently has it caused missing mesh filter references). It seems possible to rename all the generated hierarchy nodes on model import (OnPostprocessMeshHierarchy) but this doesn't affect the actual UnityEngine.Mesh instances in the asset. Is there some recommended way to deal with this? Can we override the name on import somehow? Force generating unique names? Should it be fixed in some FBX export step instead? Seems like it would be rather common but I'm not finding much posting about it.