There is a buffer "*Char Help*" that emacs makes sure the user is never
able to copy. (What if Stallman found out about this?)

First, if the user tries C-x o, to maneuver from the minibuffer into the
*Char Help* buffer, emacs already knows the user will try this trick,
and thwarts it right away, despite C-x not being explicitly listed in
the prompt,