trackball right click not working in Qt 5.12.1

Customers tells me that no QGraphicsView::mouseReleased() event is being generated using right-click on his Logitech trackball model T-BC21 using Qt 5.12.1, left click works fine. The trackball right and left click works fine on a version of the software built using Qt 5.12.0. Standard mice left and right click work fine using Qt 5.12.1. I don't have access to this trackball device to verify.