(defvar popup-buffer-minibuffer-message-window nil)
(defun popup-buffer-minibuffer-message-clear ()
  (when (not noninteractive)
    (when (timerp minibuffer-message-timer)
      (cancel-timer popup-buffer-minibuffer-message-timer)
      (when (live-window-p popup-buffer-minibuffer-message-window)
	(delete-window popup-buffer-minibuffer-message-window)))))
(defun popup-buffer-minibuffer-message-set (message)
  (let* ((minibuf-window (active-minibuffer-window))
         (minibuf-frame (and (window-live-p minibuf-window)
                             (window-frame minibuf-window))))
    (when (and (not noninteractive)
               (window-live-p minibuf-window)
               (or (eq (window-frame) minibuf-frame)
                   (eq (frame-parameter minibuf-frame 'minibuffer) 'only)))
      (progn
        (when (numberp minibuffer-message-clear-timeout)
          (setq popup-buffer-minibuffer-message-timer
                (run-with-timer minibuffer-message-clear-timeout nil
                                #'popup-buffer-minibuffer-message-clear)))
	(let ((buffer (get-buffer-create " *Popup Echo Area*")))
	  (unless (window-live-p popup-buffer-minibuffer-message-window)
	    (setq popup-buffer-minibuffer-message-window
		  (display-buffer
		   buffer
		   '(display-buffer-in-side-window
		     (side . bottom)
		     (window-height . 1)))))
	  (with-current-buffer buffer
	    (setq-local mode-line-format nil cursor-type nil)
	    (erase-buffer)
	    (insert message)))
	t))))
(setq clear-message-function #'popup-buffer-minibuffer-message-clear)
(setq set-message-function #'popup-buffer-minibuffer-message-set)