(defun bug-match-data-marker-clobber ()
  (interactive)
  (with-current-buffer (get-buffer-create "*test*")
    (display-buffer (current-buffer))
    (erase-buffer)
    (insert "1234567890\n")
    (insert "abcdefghilk\n")
    (make-local-variable 'after-change-functions)
    (let* ((after-change-functions `
            (,(lambda (&rest _)
                (let ((inhibit-modification-hooks nil)
                      (after-change-functions nil))
                  (save-excursion
                    (save-match-data
                      (goto-char (point-min))
                      (looking-at "[0-9]")
                      (delete-char 1))
                    ;; match-data is restored, but markers have a
                    ;; different position now, because of the
                    ;; deletion.
                    ;;
                    ;; (match-data) ;=> (#<marker@11> #<marker@17>)
                    ))))))
      (search-backward "abcdef")
      ;; (match-data) ;=> (#<marker@12> #<marker@18>)
      (replace-match "ABCDEF" t t) ;; Triggers `after-change-functions'.
      )))

(setq debug-on-error t)
(define-key global-map [f12] 'bug-match-data-marker-clobber)