Just got a very strange bug when use QFileDialog. If I open files using double click on filename, everything works just fine. But if I select file and then press Open, the first time file is opened correctly, but the second time program hangs. Combining double click and Open doesn't lead to hang. Only two sequential opening using Open causes program hang. Debugging doesn't show any differences between those open variants. Maybe something wrong with threads, but I can't understand what exactly.

Any ideas are highly appreciated. Thanks.