threadBoth issue

[incubo4u]

when trying to use the
"threadBoth" program crash and get the following message :

2020-09-02 13:48:52.000 Python[82219:9661369] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'NSWindow drag regions should only be invalidated on the Main Thread!'
*** First throw call stack:
(
0 CoreFoundation 0x00007fff2f7f3d07 __exceptionPreprocess + 250
1 libobjc.A.dylib 0x00007fff685175bf objc_exception_throw + 48
2 CoreFoundation 0x00007fff2f81c50c -[NSException raise] + 9
3 AppKit 0x00007fff2ca2324c -[NSWindow(NSWindow_Theme) _postWindowNeedsToResetDragMarginsUnlessPostingDisabled] + 310
4 AppKit 0x00007fff2ca0acb2 -[NSWindow _initContent:styleMask:backing:defer:contentView:] + 1416
5 AppKit 0x00007fff2ca0a723 -[NSWindow initWithContentRect:styleMask:backing:defer:] + 42
6 AppKit 0x00007fff2cd435d8 -[NSWindow initWithContentRect:styleMask:backing:defer:screen:] + 52
7 libqcocoa.dylib 0x0000000111ff7195 qt_plugin_instance + 161509
8 libqcocoa.dylib 0x0000000111fe4aac qt_plugin_instance + 86012
9 libqcocoa.dylib 0x0000000111fde722 qt_plugin_instance + 60530
10 libqcocoa.dylib 0x0000000111fde1ab qt_plugin_instance + 59131
11 QtGui 0x000000010c1d922c _ZN14QWindowPrivate6createEby + 140
12 QtWidgets 0x000000010bc2e6d1 _ZN14QWidgetPrivate6createEv + 1201
13 QtWidgets 0x000000010bc2d3c2 _ZN7QWidget6createEybb + 322
14 QtWidgets 0x000000010bc40a7d _ZN14QWidgetPrivate10setVisibleEb + 189
15 cv2.cpython-38-darwin.so 0x0000000107186390 _ZN8CvWindowC2E7QStringi + 752
16 cv2.cpython-38-darwin.so 0x000000010717bc18 _ZN11GuiReceiver12createWindowE7QStringi + 296
17 cv2.cpython-38-darwin.so 0x000000010717ba1a cvNamedWindow + 570
18 cv2.cpython-38-darwin.so 0x000000010717e8d7 _ZN11GuiReceiver9showImageE7QStringPv + 471
19 cv2.cpython-38-darwin.so 0x000000010717e63c cvShowImage + 604
20 cv2.cpython-38-darwin.so 0x0000000107176266 _ZN2cv6imshowERKNSt3__112basic_stringIcNS0_11char_traitsIcEENS0_9allocatorIcEEEERKNS_11_InputArrayE + 358
21 cv2.cpython-38-darwin.so 0x0000000106053846 ZL18pyopencv_cv_imshowP7_objectS0_S0 + 470
22 Python 0x00000001058555e6 cfunction_call_varargs + 171
23 Python 0x00000001058550d5 _PyObject_MakeTpCall + 274
24 Python 0x00000001058f48b7 call_function + 804
25 Python 0x00000001058ee40d _PyEval_EvalFrameDefault + 13137
26 Python 0x000000010585591a function_code_fastcall + 106
27 Python 0x0000000105857a32 method_vectorcall + 256
28 Python 0x0000000105855361 PyVectorcall_Call + 108
29 Python 0x00000001058ee701 _PyEval_EvalFrameDefault + 13893
30 Python 0x000000010585591a function_code_fastcall + 106
31 Python 0x00000001058f46ed call_function + 346
32 Python 0x00000001058ee3ed _PyEval_EvalFrameDefault + 13105
33 Python 0x000000010585591a function_code_fastcall + 106
34 Python 0x00000001058f46ed call_function + 346
35 Python 0x00000001058ee3ed _PyEval_EvalFrameDefault + 13105
36 Python 0x000000010585591a function_code_fastcall + 106
37 Python 0x0000000105857a32 method_vectorcall + 256
38 Python 0x0000000105855361 PyVectorcall_Call + 108
39 Python 0x000000010596a8be t_bootstrap + 74
40 Python 0x000000010592c040 pythread_wrapper + 25
41 libsystem_pthread.dylib 0x00007fff698c3109 _pthread_start + 148
42 libsystem_pthread.dylib 0x00007fff698beb8b thread_start + 15
)
libc++abi.dylib: terminating with uncaught exception of type NSException
zsh: abort python3 thread_demo.py --thread both

[nrsyed]

I'm not familiar with this error. Based on a search and the stack trace, it seems like it's related to macOS and Qt, which I don't have experience with. Maybe one of these links is useful?

opencv/opencv-python#115
https://stackoverflow.com/questions/40443825/opencv-crashes-when-reopening-camera-on-mac-osx-sierra-and-displaying