I'm currently using this advice:
```elisp
;;; prepend comment char ahead of `org-babel-ref'.
;; auto prefix with comment char when create code ref in src block with
`org-store-link'.
(defun org-babel-ref-prepend-comment-char (arg &optional interactive?)
  "Prepend comment chart in Org-mode src code block."
  (when (org-src-edit-buffer-p)
    (comment-dwim nil)
    (insert " ")))

(advice-add 'org-store-link :before #'org-babel-ref-prepend-comment-char)
```

There is another solution but not work:
```elisp
;;; Another implement solution.
(defun org-src-coderef-format (&optional element)
  (cond
   ((and element (org-element-property :label-fmt element)))
   ((org-src-edit-buffer-p) (org-src-do-at-code-block
(org-src-coderef-format)))
   ((org-element-property :label-fmt (org-element-at-point)))
   (t org-coderef-label-format)))

(defun org-src-coderef-prepend-comment-char (args)
  "Prepend comment chart in Org-mode src code block."
  (when (org-src-edit-buffer-p)
    (comment-dwim nil)
    (insert " ")))

(advice-add 'org-src-coderef-format :filter-return
            #'org-src-coderef-prepend-comment-char)
```

I think this function should be in Org-mode itself.
Because when you're editing the source code, will not want this src-coderef
like `(ref:example)` be editable. It should be in comment.

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