The list used to show the first few characters of each key followed by an ellipsis. That was only ever a stored fragment, but it read as though the whole key was on file and had merely been shortened for display.
Magpie stores a one-way hash of a key and nothing else. A key is shown once, when it is created, and cannot be recovered afterwards — revoke it and create another. The list now shows each key by its name, when it was created and when it was last used.