diff --git a/lisp/mail/footnote.el b/lisp/mail/footnote.el
index 202e5528060..fc74122ecd2 100644
--- a/lisp/mail/footnote.el
+++ b/lisp/mail/footnote.el
@@ -868,7 +868,7 @@ advice, and FUNCTION is what'll be added as an :around advice."
        ;; nil and `ignore' have the same semantics for adaptive-fill-function,
        ;; but only `ignore' behaves correctly with add/remove-function.
        (setq-local ,variable #'ignore))
-     (remove-function (local ',variable) #'function)
+     (remove-function (local ',variable) #',function)
      (when ,mode
        (add-function :around (local ',variable)
                      #',function))))