How can I install Emacspeak?

Question

I find some lengthy instructions on the website, but I also see that's it's available with use-package, but I get an error

Debugger entered--Lisp error: (void-function ems-generate-switcher)
  (ems-generate-switcher 'emacspeak-toggle-comint-output-monitor 'emacspeak-comint-output-monitor "Toggle  Emacspeak comint monitor.\nInteractive PREF...")
  straight--activate-package-autoloads((:type git :host github :repo "emacsmirror/emacspeak" :package "emacspeak" :local-repo "emacspeak"))
  #f(compiled-function () #<bytecode -0x3e04d585741863d>)()
  straight--transaction-exec(use-package-\"aa16322d8f05a75fc1c05b6a313aa48e\"-nil-nil :now #f(compiled-function () #<bytecode -0x3e04d585741863d>))
  straight-use-package(emacspeak)
  (progn (straight-use-package 'emacspeak) (defvar use-package--warning310 #'(lambda (keyword err) (let ((msg (format "%s/%s: %s" ... keyword ...))) (save-current-buffer (set-buffer (get-buffer-create "*use-package*")) (goto-char (point-max)) (insert "-----\n" msg "\n\n(use-package emacspeak :ensure t)\n\n  -->\n\n(use-p...") (emacs-lisp-mode)) (setq msg (concat msg " (see the *use-package* buffer)")) (display-warning 'use-package msg :error)))) (condition-case err (let ((now (current-time))) (message "%s..." "Loading package emacspeak") (prog1 (if (not (require 'emacspeak nil t)) (display-warning 'use-package (format "Cannot load %s" 'emacspeak) :error)) (let ((elapsed (float-time ...))) (if (> elapsed 0.1) (message "%s...done (%.3fs)" "Loading package emacspeak" elapsed) (message "%s...done" "Loading package emacspeak"))))) ((debug error) (funcall use-package--warning310 :catch err))))
  elisp--eval-last-sexp(nil)
  #<subr eval-last-sexp>(nil)
  apply(#<subr eval-last-sexp> nil)
  eval-last-sexp(nil)
  funcall-interactively(eval-last-sexp nil)
  call-interactively(eval-last-sexp nil nil)
  command-execute(eval-last-sexp)

Or any other simpler instructions available than what is on their website?

I also find no proper tags to use, like "#emacspeak", #blind, for use on this topic.

EDIT; Ok, this works, if I launch emacs like this: emacspeak

, but I don't want to do that.

Is there something which needs to launch before starting Emacs, maybe?