Crash and how to fix it

[JohnTailor]

If the mouse is moved fast while dragging a rect, the app crashes (on Windows, Python 3.9). The GUI seems to be overloaded. This can be fixed as follows.

In the beginning of selectwindows add
from timeit import default_timer as timer
lastt=timer()

In the beginning of def dragrect(event, x, y, flags, dragObj):
global lastt
ctime=timer()
gap=ctime-lastt
if gap < 0.1 and event == cv2.EVENT_MOUSEMOVE: return
lastt = ctime

You can change the 0.1 to sth larger or a bit smaller.