[[!comment format=mdwn
 username="joey"
 subject="""comment 3"""
 date="2023-08-22T19:02:26Z"
 content="""
This is certainly adjacent to unused, but it's not quite the same.

I think users will generally want this to list keys even if they are 
still used by some other files in the tree besides the files that they
are querying. (There may be cases where that is not desirable of course,
but at least 3 of the 4 examples I came up with seem desirable to operate
that way.)

And a key listed by this command might be used by other branches, so unused
would not list it.
"""]]
