anchor.diff:     (prompter:constructor (get-data (bookmarks-path (current-buffer))))
      (prompter:active-properties '(:url :title :tags))))
   
  -;; (export-always 'tag-suggestion-filter)
  -;; (declaim (ftype (function (&key (:with-empty-tag boolean)
  -;;                                 (:extra-tags list-of-tags)))
  -;;                 tag-suggestion-filter))
  -(defun tag-suggestions (&key with-empty-tag extra-tags)
  -  "When with-empty-tag is non-nil, insert the empty string as the first tag.
  -This can be useful to let the user select no tag when returning directly."
  +(defun tag-suggestions ()
     (with-data-unsafe (bookmarks (bookmarks-path (current-buffer)))
       (let ((tags (sort (append extra-tags
                                 (mapcar (lambda (name) (make-tag :name name))
  
positive.code:                                        :test #'string-equal)))
                        #'string-lessp
                        :key #'tag-name)))
        (when with-empty-tag
          (push "" tags))
        tags
        ;; (lambda (minibuffer)
        ;;   (fuzzy-match (text-buffer::word-at-cursor (input-cursor minibuffer)) tags))
        )))
  
  (define-class tag-source (prompter:source)
    ((prompter:name "Tags")
     (extra-tags '())
     (prompter:multi-selection-p t)
     (prompter:constructor (lambda (source)
                             (tag-suggestions :extra-tags (extra-tags source)))))
  
negative.code:         (let* ((body (with-current-buffer buffer
                         (ffi-buffer-get-document buffer)))
                 (tags (prompt
                        :prompt "Tag(s)"
                        ;; :default-modes '(set-tag-mode minibuffer-mode) ; TODO: Replace completion.
                        :input (url-bookmark-tags (url buffer))
                        :sources (list
                                  (make-instance 'prompter:word-source
                                                 :name "New tags"
                                                 :multi-selection-p t)
                                  (make-instance 'tag-source
                                                 :extra-tags (make-tags (extract-keywords body 5)))))))
            (bookmark-add (url buffer)
                          :title (title buffer)
                          :tags tags)
  