Unable to use QMacCocoaViewContainer

1. Trying to use QMacCocoaViewContainer in a totally different widget. Then when trying to interact with QTableView, the output debug log is full of
"QNSView mouseDragged: Internal mouse button tracking invalid (missing Qt::LeftButton)"
entries
Resizing of columns in QTableView becomes slow and buggy.

2. In a real application can also cause crashes and hangs!
3. To reproduce in the demo app:
-> press left mouse button in any place in table view, keep holding it and then move the cursor up to the table view horizontal header.
OR
-> Do a fast re-sizing of columns in the test app
4. Demo project is attached.
5. Screenshots also attached
6. The patch provided for qnsview.mm by Morten Sørvig at QTBUG-37926 didn't help.

Update: QNSView mouseDragged error somehow depends on setAttribute(Qt::WA_MacShowFocusRect);

Update 2 Please see this video for quick demonstration:
https://www.dropbox.com/s/49ynrsd9b1rry8e/QTBUG-40583.mp4?dl=0
(download to see in hi-res)

Update 3 Fast resizing of columns causes problems in TableView widget, see video.

Update 4 Also noticed the same issues in QSpinBox if some other widget is using QMacCocoaViewContainer