hi,
not sure whether Qt has something to do with this, I took a look at the qt window of opencv by make the opencv from source with "WITH_QT" flag and find that the qt window block my right mouse button event, so I reinstall all of the opencv without qt.
Now something strange happened. The default imshow window with WINDOW_NORMAL flag cannot decrease size now. It would pop-up the origin size of the image (not a resize one) and the user can only increase the window size, but not decrease. Even I reinstall the opencv the problem is still here.
It seems as the same issue as here in the past :
https://answers.opencv.org/question/60288/opencv30-windows_normal-flag-not-working/
and here
https://github.com/opencv/opencv/issues/13995
but it's still no solution