There is a PlayableAsset that used to use Custom Track and Custom Clip. I deleted the related script(Custom Track, Clip) And I can no longer see the elements related to it on PlayableAsset. This causes the following warning. "The referenced script (Unknown) on this Behaviour is missing!" In fact, if i open a Playable file through Text Editor and read YAML, There's a lot of dirty data that i don't use. This seems to be causing an error. I want to delete the Dirty data that are not actually used. But in unity editor, i can't see any element of dirty things. i try AssetDatabase.ForceReserializeAsets and Reimport, but does not resolve. How do I solve this problem?