Addendum:
I just tried if the same applied to terminal Emacs by launching it with `emacs -nw` and it does not (presumably because Super and Hyper are not passed from the terminal emulator to Emacs itself).
I was able to work around the bug by using `(define-key key-translation-map (kbd "H-<down>") (kbd "<down>"))` etc. for all ISO_Level5 keys but that is a bit too cluncky and static for my tastes. Is there a way to just translate every "H-" binding to just not have the modifier applied? Is there a list of all possible keys Emacs accepts and that I can use to just `map` over the `define-key` statement.
xmodmap output:
```
xmodmap: up to 3 keys per modifier, (keycodes in parentheses):
shift Shift_L (0x32), Shift_R (0x3e)
lock Shift_L (0x32)
control Control_L (0x40), Control_R (0x69)
mod1 Alt_L (0x85), Meta_L (0xcd)
mod2 BadKey (0xcf)
mod3 ISO_Level5_Shift (0xcb)
mod4 Super_L (0x25), Super_R (0x86), Super_L (0xce)
mod5 ISO_Level3_Shift (0x5c)
```