Shortcut Ctrl+5 (Qt 5.9.5), on a US keyboard, it works correctly, on a french keyboard, we need to press Ctrl+Shift+5. 

Steps to reproduce:

1. Open settings of your system, choose Time & Language.
2. Under Languages, Add a language "French (Belgium)". Choose it as the default language.
3. Execute the attached project. 
4. Press Ctrl+5
5. Output window shows "Undo Menu selected" in case of Qt 5.6.3. But in case Qt 5.9.5, user has to press Ctrl+shift+5 for this. 

Note: I am not sure if this is expected behavior or some bug got introduced. So, raising this defect for developer team's view. As to Type 5 with French language chosen, we have to press shift+5 with our keyboard.