Change password ticket result url does not include custom error message

I’m having trouble getting the custom error message the Change Password database action script returns on error to be appended to the result url when I create change password tickets.

The default Change Password script template comments says the following:

  // There are three ways that this script can finish:
  // 1. The user's password was updated successfully:
  //     callback(null, true);
  // 2. The user's password was not updated:
  //     callback(null, false);
  // 3. Something went wrong while trying to reach your database:
  //     callback(new Error("my error message"));

    // If an error is returned, it will be passed to the query string of the page
  // where the user is being redirected to after clicking the confirmation link.
  // For example, returning `callback(new Error("error"))` and redirecting to
  // https://example.com would redirect to the following URL:
  //     https://example.com?email=alice%40example.com&message=error&success=false

I’m trying this as a test:

function changePassword (email, newPassword, callback) {
    callback(new Error('error message'));
}

But the redirect url always looks like this:

http://localhost:3000/?email=foo%40bar.com&success=false&message=The%20operation%20cannot%20be%20completed.%20Please%20try%20again.

Am I misinterpreting this expected behaviour here or is something not working as expected?