xev to try to capture the keycode, but I don't get any output from it. I get output for the rest of the keys I checked. This happened after my system froze (likely the fault of VirtualBox) so I wonder if it has anything to do with it.
I just found out that it's functionality is actually swapped with that of Fn key (the special key that allow me, for example, to press it in combination with another to change screen brightness, speaker loudness, ...). How do I swap it back?
Note that before discovering that this was merely a key swap, I actually did a reinstall in desperation, and even poked around the (badly-designed) BIOS interface (this is a HP Probook 4350s) to see if I screwed up with anything.