Shift+F10 is the default shortcut for opening the context menu on windows. This used to work in Qt 4.8.5 but is broken in Qt 5.2.1-5.3.1 (and possibly earlier Qt5 versions, which I did not test).

Steps to reproduce using Windows 7 and the test application in the attachment (it's just a QTextEdit in a default-generated Qt-Widget application):

1) Qt 4.8.5
1 a) Compile with Qt 4.8.5
1 b) Place the cursor in the text edit and press Shift+F10.
Result: The context menu appears (as expected).

2) Qt 5.3.1
2 a) Compile with Qt 5.3.1
2 b) Place the cursor in the text edit and press Shift+F10.
Result: Nothing happens.
Expected: The context menu should appear.