Autoload, default status, input lags

Dear Nicolas,

First, thanks a lot for this library !

I followed the readme file and added the small piece of code in my init but I am facing issues with it :

I have to manually do M-x mu4e-thread-folding-mode to activate the folding mode, is there a way to automatically load this mode on start of mu4e ? did I miss something ?
When loaded, I see everything unfolded by default (I see every emails), I'd like to see everything folded instead such that I can manually expand a pack of emails. I tried to change the variable mu4e-thread-folding-default-view from folded to unfolded, restart mu4e, but no changes.
When manually folding emails, there is a severe input lag when I navigate over the lines with the up/down arrow. It seems to be when I pass over starred emails.

I pasted my configuration below.

Thanks a lot

;; Add mu4e to the load-path:
(add-to-list 'load-path "/usr/share/emacs/site-lisp/mu4e")
(require 'mu4e)
(setq mu4e-headers-list-mark      '("s" . " ")) ; mailing list
(setq mu4e-headers-personal-mark  '("p" . " ")) ; personal
(setq mu4e-headers-calendar-mark  '("c" . "🗓️")) ; calendar
(setq mu4e-headers-unread-mark    '("u" . "📩 "))
(setq mu4e-headers-draft-mark     '("D" . "🚧 "))
(setq mu4e-headers-flagged-mark   '("F" . "⭐ "))
(setq mu4e-headers-new-mark       '("N" . "🆕 "))
(setq mu4e-headers-passed-mark    '("P" . "↪ "))
(setq mu4e-headers-replied-mark   '("R" . "↩ "))
(setq mu4e-headers-seen-mark      '("S" . " "))
(setq mu4e-headers-trashed-mark   '("T" . "🗑️"))
(setq mu4e-headers-attach-mark    '("a" . "📎 "))
(setq mu4e-headers-encrypted-mark '("x" . "🔑 "))
;; (setq mu4e-headers-signed-mark    '("s" . "🖊 "))

;; mu4e Threads
(require 'mu4e-thread-folding)
(add-to-list 'mu4e-header-info-custom
             '(:empty . (:name "Empty"
                         :shortname ""
                         :function (lambda (msg) "  "))))
(setq mu4e-headers-fields '((:empty         .    2)
                            (:human-date    .   12)
                            (:flags         .    6)
                            (:mailing-list  .   10)
                            (:from          .   22)
                            (:subject       .   nil)))

(define-key mu4e-headers-mode-map (kbd "<tab>")     'mu4e-headers-toggle-at-point)
;; (define-key mu4e-headers-mode-map (kbd "<left>")    'mu4e-headers-fold-at-point)
;; (define-key mu4e-headers-mode-map (kbd "<S-left>")  'mu4e-headers-fold-all)
;; (define-key mu4e-headers-mode-map (kbd "<right>")   'mu4e-headers-unfold-at-point)
;; (define-key mu4e-headers-mode-map (kbd "<S-right>") 'mu4e-headers-unfold-all)

;; Boite
(setq
   user-mail-address "XXXXXX"
   user-full-name  "Joubine Aghili")
(setq mu4e-drafts-folder "XXXXXXXX")
(setq mu4e-sent-folder   "XXXXXXXX")
(setq mu4e-trash-folder  "XXXXXXXX")
(setq mu4e-get-mail-command "mbsync --config XXXXXXXXXXXX")

;; Further customization:
(setq mu4e-html2text-command "w3m -T text/html" ; how to hanfle html-formatted emails
      mu4e-update-interval 300                  ; seconds between each mail retrieval
      mu4e-headers-auto-update t                ; avoid to type `g' to update
      mu4e-view-show-images t                   ; show images in the view buffer
      mu4e-compose-signature-auto-include nil   ; I don't want a message signature
      mu4e-use-fancy-chars t                    ; allow fancy icons for mail threads
      mu4e-confirm-quit nil                     ; Don't ask to quit... just quit
      message-kill-buffer-on-exit t
      mu4e-compose-dont-reply-to-self t
)

;; SMTP settings:
(require 'smtpmail)
(use-package auth-source
  :ensure nil
  :custom
  (auth-sources '("XXXXXXXXXXXXXXXX")))

(setq smtpmail-smtp-user  "XXXXXXXXXXXXXX")
(setq smtpmail-smtp-server  "XXXXXXXXXXXXX") ; host running SMTP server
(setq smtpmail-smtp-service  587)               ; SMTP service port number
(setq smtpmail-stream-type 'starttls)          ; type of SMTP connections to use
(setq send-mail-function 'smtpmail-send-it)    ; should not be modified
(setq smtpmail-debug-verbose t)
(setq smtpmail-debug-info t)
(setq smtpmail-servers-requiring-authorization ".*")

rougier / mu4e-thread-folding

Autoload, default status, input lags #31