Drag and drop by touching on Boot2Qt device does not show object being dragged at the correct position in the first place (Wayland)

Reproducer attached. One needs a touch screen for Boot2Qt device.

Way to reproduce the issue is to first launch our qwindow-compositor example. Then launch the reproducer with "platform -wayland". Launching 2 apps via appcontroller can be problematic, so one may need to ssh into device, and

export XDG_RUNTIME_DIR=<some dir>

first and then launch the compositor and reproducer in console. In this case, the "blink" is much more obvious (although may not be necessarily at certain corner).

Another issue with qwindow-compositor case is when, say one first drag and element with mouse but disconnect mouse midways (before releasing it to the other side). Then this drag-and-drop fails and element does not move. But then if one try to touch and drag that element again, it "flashes" at where it was left in the previous drag-and-drop by mouse.

The same issue is not observed on desktop Linux with Wayland compositor. Seems to be on Yocto only. And also seems to be affecting only touch. Dragging by mouse does not cause the "flash".