Thanks for your help, Tomas, here is the beginning of my init.el (suggestions to improve it are of course welcome):
(defvar last-file-name-handler-alist file-name-handler-alist) (setq gc-cons-threshold 602653184 gc-cons-percentage 0.6 file-name-handler-alist nil) ;;; General configuration section ;; Dumped Emacs ;; (when (boundp 'galactic-emacs-pdumper-dumped) ;; ;; Restore `load-path' ;; (setq load-path galactic-emacs-pdumper-load-path) ;; When Emacs starts from dump file, some default modes are not ;; enabled ;; (global-font-lock-mode) ;; (transient-mark-mode)) (when (> emacs-major-version 23) (require 'package) (package-initialize) (add-to-list 'package-archives '("melpa" . "http://melpa.milkbox.net/packages/") 'APPEND)) ;; Configure Emacs package manager. Not required anymore on Emacs > 27 (if (version< emacs-version "27") (package-initialize) ) (require 'package) (setq package-archives '(("melpa" . "https://melpa.org/packages/") ("melpa-stable" . "https://stable.melpa.org/packages/") ("org" . "https://orgmode.org/elpa/") ; ("gnu" . "https://elpa.gnu.org/packages/") )) ;; Some combination of GNU TLS and Emacs fail to retrieve archive ;; contents over https. ;; https://www.reddit.com/r/emacs/comments/cdei4p/failed_to_download_gnu_archive_bad_request/etw48ux ;; https://debbugs.gnu.org/cgi/bugreport.cgi?bug=34341 (if (and (version< emacs-version "26.3") (>= libgnutls-version 30600)) (setq gnutls-algorithm-priority "NORMAL:-VERS-TLS1.3")) ;; Enable packages signature verification only if GPG is installed (setq package-check-signature (when (executable-find "gpg") 'allow-unsigned)) ;; Change the below priorities if you prefer melpa-stable packages. ;; Higher is better. (setq package-archive-priorities '( ("melpa" . 4) ("melpa-stable" . 3) ("org" . 2) ("gnu" . 1) ) ) ;; Bootstrap `use-package' (unless (package-installed-p 'use-package) (package-refresh-contents) (package-install 'use-package)) (eval-when-compile (require 'use-package)) (use-package use-package-ensure-system-package :ensure t) (setq package-enable-at-startup nil) ;; addendum from scimax (require 'package) (add-to-list 'package-archives '("melpa" . "http://melpa.milkbox.net/packages/") t) (package-initialize) (when (not package-archive-contents) (package-refresh-contents)) -- Joseph