Emacs: Use versioned ELPA directory if present

.emacs.d/init.el

@@ -33,6 +33,11 @@
   ;;   emacs melpa invalid: certificate host does not match hostname
   ;; Try the following:
   ;;   (setq tls-checktrust nil)
+  ;; Different Emacs version have different byte code.  If a versioned ELPA
+  ;; directory is found, use it.
+  (let ((versioned-dir (format "elpa-%s.%s" emacs-major-version emacs-minor-version)))
+    (when (member versioned-dir (directory-files (expand-file-name ".." package-user-dir)))
+      (setq package-user-dir (expand-file-name (concat "../" versioned-dir) package-user-dir))))
   (setq package-archives '(("gnu" . "https://elpa.gnu.org/packages/")))
   (add-to-list 'package-archives '("melpa" . "https://melpa.milkbox.net/packages/"))
   (add-to-list 'package-archives '("org" . "https://orgmode.org/elpa/") t)