additionalData

Object containing additional data about the 3DS request that is beyond the EMV 3DS standard spec (e.g., specific fields that only certain card networks send but are not required across all 3DS requests).

Sets Builder.additionalData to an arbitrary JSON value.

You should usually call Builder.additionalData with a well-typed AdditionalData value instead. This method is primarily for setting the field to an undocumented or not yet supported value.