anchor.diff:                                                     ;; e.g. progress bars.
                                                      (write (ps:lisp (markup:markup
                                                                       (:code (str:replace-all " " " " s))
  -                                                                    (:br)))))))))))
  +                                                                    (:br)))))))))
  +        (ffi-buffer-evaluate-javascript-async
  +         buffer
  +         (ps:ps (ps:chain document
  +                          (write (ps:lisp (markup:markup (:p "Done.")))))))))
       (set-current-buffer buffer)
       buffer))
   
  
positive.code: 
  (define-mode os-package-manager-mode ()
    "Mode for package management."
    ())
  
  ;; TODO: Add command to interrupt operation?
  ;; (uiop:terminate-process  process-info)
  
  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  (in-package :nyxt)
  
negative.code:                                       (ps:lisp content)))))
      (ffi-buffer-evaluate-javascript-async buffer insert-content)
      (chanl:pexec ()
        (let ((process-info (funcall command packages profile))
              (mode (find-submode buffer 'os-package-manager-mode)))
          (setf (nyxt/os-package-manager-mode:current-process-info mode) process-info)
          (ffi-buffer-evaluate-javascript-async
           buffer
           (ps:ps (ps:chain document
                            (write (ps:lisp (markup:markup
                                             (:p
                                              (:a :class "button"
                                                  :href (lisp-url '(nyxt/os-package-manager-mode:cancel-package-operation))
                                                  "Cancel"))))))))
          (format-command-stream process-info
                                 (lambda (s)
                                   (ffi-buffer-evaluate-javascript-async
  