Here we would like to draw your attention to WCF_ML_FIELDS transaction code in SAP. As we know it is being used in the SAP CA-WUI (WebClient UI in CA) component which is coming under CA module (Cross Application).WCF_ML_FIELDS is a transaction code used for Maintain Fields for Mixed List in SAP.
It comes under the package WCF_MIXED_LIST_UI.
Transaction WCF_ML_FIELDS technical data table
|Purpose||Maintain Fields for Mixed List|