In my code, I have a QApplication, which has a default menuBar object. I have added various menus to the menuBar and the menu appears just fine on MacOSX, Windows, and Linux (using the Unity Desktop Environment). However, the menu bar simply appears black when the program is built on a SUSE machine using KDE. We seem to have a similar response on RHEL7. You can still access the menuBar by clicking on it, but the text does not appear until you click on the black portion of the screen that represents the menubar.