URL: https://docs.unity3d.com/ScriptReference/../Manual/../ScriptReference/ArrayUtility.IndexOf.html
ser: { user_unity_id: undefined, user_logged_in: 'no' }, environment: { environment_locale: 'en-us', environment_currency: undefined }});int The zero-based index of the element, if found; otherwise -1.
Index of first element with value value.