Alt+Numpad Delete doesn't work
I'm using v3.18.0 on Fedora 26, on an x86_64 PC.
If I want to delete an addition segment, I can use Alt + Delete to delete it... provided that it's the Delete that's not on the numpad, i.e. the bottom-left key out of the 2x3 group to the left of the Numpad see here here.
If I use Alt + Numpad-Delete, nothing happens. (My Num-lock is off, of course.)