Can not generate XML file for applications in 3.8.1

Hello, We do not succeed anymore in generating XML file for applications in the 3.8.1 version. We choose an application. No inconsistencies or errors on the application, we can click on the "generate XML" button. So we click on it. Then, Rollbase should open a new window with the generated XML file but Rollbase goes back to the previous screen and nothing happened. May be someting has changed in the 3.8 and we do something wrong now. Can you help us to unblock this situation ? Thank you for your help. Regards, Matthieu