QApplication::setStyle() missing "windowsvista" style

If you place Qt 5.14 dlls (like Qt5Core.dll, Qt5Gui.dll etc.) inside the application build directory (like build/Debug or build/Release) then the application shows up in old Windows 95 style and not in the modern Windows 10 (Vista) style. In this case you even not able to force the application to run in Vista style if you use QApplication::setStyle("windowsvista") in its main.cpp file.

In all Qt 5.13.2 and prior Qt versions this did not happen: An applications shows up in modern Vista style even if Qt Dlls are placed inside its build directory.

I suppose this can't be called a bug so this report might be closed. But it's not ideal for application testing during application developement how Qt 5.14 changed its behaviour in this case.