原先在 nov-mode 中点击正文里的注释链接，会跳到注释，然后点击注释的链接又会跳回原文，这样反复跳跃很影响阅读体验。我自己能写简单的 elisp 但对 epub 和 nov.el 的具体原理不了解，于是用 Gemini 3 试了一下。
下面代码会让 nov-mode 直接在 echo area 中预览注释的内容，而目录页的链接直接跳转不会预览。另外让 Gemini 写了一个函数作为预览行为的开关（有时在非目录页也需要跳转而非预览）。大概交互了五次之后就彻底实现，目前测试了五本电子书，未发现问题，非常满意。（不过后来用gemini 试了一些更复杂的 elisp 任务又不行了orz）
(with-eval-after-load 'nov
;; 1. DEFINITION: The Toggle Variable
(defvar nov-enable-link-peeking t
"When non-nil, preview internal links in the minibuffer instead of jumping.
This is automatically disabled when viewing the Table of Contents.")
;; 2. COMMAND: Toggle Function
(defun nov-toggle-link-peeking ()
"Toggle the peeking behavior for internal links."
(interactive)
(setq nov-enable-link-peeking (not nov-enable-link-peeking))
(message "Link peeking %s" (if nov-enable-link-peeking "enabled" "disabled")))
;; 3. HELPER: The Smart Content Fetcher
(defun nov-content-at-target (filename target)
"Retrieve text content from FILENAME at anchor TARGET.
Smartly handles duplicates by ignoring self-referencing links (source anchors)
while accepting back-links (target anchors)."
(let* ((current-path (cdr (aref nov-documents nov-documents-index)))
(directory (file-name-directory current-path))
(full-path (if (or (null filename) (string= filename ""))
current-path
(if (file-name-absolute-p filename)
filename
(file-truename (nov-make-path directory filename))))))
(when (file-exists-p full-path)
(with-temp-buffer
(insert-file-contents full-path)
(let* ((dom (libxml-parse-html-region (point-min) (point-max)))
;; A "real" target has the ID but is NOT a link to that same ID
(is-real-target-p
(lambda (node)
(and (equal (dom-attr node 'id) target)
(let ((href (dom-attr node 'href)))
(or (null href)
(not (string-suffix-p (concat "#" target) href)))))))
(node (seq-find is-real-target-p (dom-search dom is-real-target-p))))
(when node
;; If the node is inline, find its block-level parent
(when (memq (dom-tag node) '(a span sup sub em strong i b font small))
(setq node
(or (seq-find (lambda (block)
(dom-search block is-real-target-p))
(append (dom-by-tag dom 'li)
(dom-by-tag dom 'aside)
(dom-by-tag dom 'p)
(dom-by-tag dom 'div)
(dom-by-tag dom 'dd)))
node)))
(replace-regexp-in-string "[ \t\n]+" " " (dom-texts node " "))))))))
;; 4. OVERRIDE: The Logic to Check TOC and Toggle State
(defun nov-browse-url (&optional mouse-event)
"Follow external links, or preview internal footnotes if enabled and valid."
(interactive (list last-nonmenu-event))
(mouse-set-point mouse-event)
(let ((url (get-text-property (point) 'shr-url)))
(when (not url)
(user-error "No link under point"))
;; LOGIC CHECK:
;; 1. Is peeking enabled?
;; 2. Are we currently OUTSIDE the Table of Contents?
;; 3. Is it an internal link?
(let* ((curr-doc (aref nov-documents nov-documents-index))
(curr-id (car curr-doc))
(is-toc (eq curr-id nov-toc-id)) ;; nov.el specific check
(should-peek (and nov-enable-link-peeking
(not is-toc)
(not (nov-external-url-p url)))))
(if (not should-peek)
;; STANDARD BEHAVIOR (Jump)
(if (nov-external-url-p url)
(browse-url url)
(apply 'nov-visit-relative-file (nov-url-filename-and-target url)))
;; PEEK BEHAVIOR
(seq-let (filename target) (nov-url-filename-and-target url)
(let ((preview-text (and target (nov-content-at-target filename target))))
(if preview-text
(message "%s" preview-text)
;; Fallback to jump if peek fails
(apply 'nov-visit-relative-file (list filename target))))))))))
我个人没有这个需求，因为我一般是在手机上看书，不用鼠标。但是或许你可以把代码贴上来，让有需要的人参考一下？