QMenus remain on screen when they should not

On OSX, contextual menus should be hidden as soon as you click anywhere outside of the menu.

Qt apps do not do this which makes them stand out as non-native.

Example:
Launch a TextEdit.app document (or any Cocoa app with a right-click menu).
Bring up a contextual menu by right clicking in the document area.
The moment you click anywhere outside of the menu, the menu is hidden.

Now, open any document or source file in QtCreator.
Right click on the document area to bring up the contextual menu.
Note that you can click on the title bar and even move the Creator window around - the context menu remains on screen.
You can even open another menu in the menubar at the same time (see screenshot - I have two menus open at once and two menu items selected).

Any application written in Qt using QMenu exhibits this behaviour. It is wrong. It could also conceivably lead to other problems.