Launch the gallery example in qtquickcontrols, select a menu entry in the menubar, press any key.
On Linux (Ubuntu 14.04 and others), we get the following assert failure:
ASSERT: "e->isAccepted()" in file /home/gabi/Work/dev/qt5-stable/qtdeclarative/src/quick/items/qquickitem.cpp, line 4490
Note that if we launch qmlscene (or the compiled gallery example) in gdb, the assert doesn't fail and the key navigation works fine.
On Windows, navigation and escape keys don't have any effect.