Render /a/b/~/c as ~/c and /a/b//c as /c in the minibuffer. Such paths are equivalent per the ancient Unix rules. In practice, shadowed paths make it easier to “restart” a path quickly when entering it manually.

(with-eval-after-load 'rfn-eshadow
  (setopt file-name-shadow-properties
          '(invisible t intangible t)))

(add-hook 'after-init-hook #'file-name-shadow-mode)