When a guest user uploads a file using the OmniScript File Upload element on an LWR (Lightning Web Runtime) Experience Site, the response does not return a valid ContentDocumentId. Instead, it returns a client-generated UUID, causing ContentDocumentLink creation to fail. As a result, the uploaded file will not be associated with the intended parent record (for example, a Case).
This is expected platform behavior. The ContentDocumentId is not returned for files uploaded by guest users.
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