REG->5.9.4: Mouse tracking doesn't work with QMacCocoaViewContainer

Find the demo project attached. It creates a QMacCocoaViewContainer and NSView inside it. setMouseTracking(true) is called on the QMacCocoaViewContainer, but this call has no effect: mouseMove events are only received while a mouse button is pressed. That can be seen from watching the application output (qDebug is used to log the events).

Additionally, even when the container receives mouse events, the underlying NSView does not receive them. I'm not entirely sure whether it's by design or a bug, but seems like a bug.

This is a regression from an older version of Qt 5, but I don't know which. Probably from 5.7 or 5.8.