I am brand new in integrating PayPal to apps so I used a guide for client integration on developer websites (link). Transactions are okay and I have no problems with this integration, but I've run into some troubles because of importing PayPal reports to another system. My client's company used external softwere where they were able to use PayPal for payments and in reports there were custom data in "Reference Txn ID" field. So far, I just understand that it's and ID of some reference transaction and if I'm not mistaken, it's deprecated anyway (link). Is there any way, how to pass data into that field through this simple JS button integration? If there's not, is there any way how to show "custom" field in reports? As I can add data through "custom" property of transaction object.
Thank you very much for every hint.
