Opencv 460 console app vs. MFC app

Using opencv_world460.lib & assoc. DLL, VS2017, C++, x64, imshow, … very simple function calls. They all work in a console app, but crash in an MFC app. Tried static/dynamic and unicode/multi-byte, no difference. “imread” works in both versions, imshow will crash in MFC version. Same symptoms when trying SIFT or FLANN functions.