NullReferenceException: Object reference not set to an instance of an object (on startup)

Code:

NullReferenceException: Object reference not set to an instance of an object
at BaseEntity.InitShared () [0x00000] in <filename unknown>:0
at BaseNetworkable.Spawn (Boolean networked) [0x00000] in <filename unknown>:0
at GenericSpawner.RespawnPrefabs (Int32 numToSpawn) [0x00000] in <filename unknown>:0
at GenericSpawner.RespawnPrefabs () [0x00000] in <filename unknown>:0
at GenericSpawner.InitialSpawn () [0x00000] in <filename unknown>:0
(Filename: Line: -1)

Anyone know what this is about, or have experienced it as well? Is this because of Rust, or because of oxide?