Every now and then I get these errors while manipulating something at
REPL prompt. I'm leaving the line number in the *Messages* buffer so
that you can have a sense of how often it occurs.

--8<---------------cut here---------------start------------->8---
297:error in process filter: slime-dispatch-event: Unexpected reply: 23 (:ok ("(defun name lambda-list &body ===> body <===)" t))
298:error in process filter: Unexpected reply: 23 (:ok ("(defun name lambda-list &body ===> body <===)" t))
449:error in process filter: slime-dispatch-event: Unexpected reply: 56 (:ok ("(error ===> datum <=== &rest arguments)" t))
450:error in process filter: Unexpected reply: 56 (:ok ("(error ===> datum <=== &rest arguments)" t))
551:error in process filter: slime-dispatch-event: Unexpected reply: 184 (:ok ("(defun name lambda-list &body ===> body <===)" t))
552:error in process filter: Unexpected reply: 184 (:ok ("(defun name lambda-list &body ===> body <===)" t))
748:error in process filter: slime-dispatch-event: Unexpected reply: 30 (:ok ("(let ===> bindings <=== &body body)" t))
749:error in process filter: Unexpected reply: 30 (:ok ("(let ===> bindings <=== &body body)" t))
820:error in process filter: slime-dispatch-event: Unexpected reply: 60 (:ok ("(parse-request r)" t))
821:error in process filter: Unexpected reply: 60 (:ok ("(parse-request r)" t))
956:error in process filter: slime-dispatch-event: Unexpected reply: 271 (:ok ("(let bindings &body ===> body <===)" t))
957:error in process filter: Unexpected reply: 271 (:ok ("(let bindings &body ===> body <===)" t))
972:error in process filter: slime-dispatch-event: Unexpected reply: 302 (:ok ("(let ===> bindings <=== &body body)" t))
973:error in process filter: Unexpected reply: 302 (:ok ("(let ===> bindings <=== &body body)" t))
979:error in process filter: slime-dispatch-event: Unexpected reply: 318 (:ok ("(defun name ===> lambda-list <=== &body body)" t))
980:error in process filter: Unexpected reply: 318 (:ok ("(defun name ===> lambda-list <=== &body body)" t))
--8<---------------cut here---------------end--------------->8---

I've been using SLIME with SBCL. I don't have experience with SLIME
along with any other Lisp.

This is GNU Emacs 27.1 (build 1, x86_64-w64-mingw32) of 2020-08-21.

I appreciate any idea you might have. Thanks!