I don’t doubt you have an issue but it is highly unusual if an update should have caused it - the chance an update would cause such a thing is highly theoretic - but could be an unusual combination of hardware and software. If it were a general regression I think we would have been flooded with topics on the matter 
The control keys default to work the same way - but can be set up independently.
The only real idea to debug it would be attaching an external keyboard - then test the keys again?
Another thing to check is the type of keyboard registered in xorg.conf.d/00-keyboard.conf - but I have yet to see that being changed by an update.
Also verify your settings in the XFCE Settings Manager → Keyboard
A last straw → maybe change it to something else save and set it back.