Web Development with Clojure 3rd - Shadow.cljs REPL receiving DEBUG logs (page 123)

In chapter 5, page 123 the reader of the book is instructed to start the Shadow.cljs REPL with:
$ npx shadow-cljs cljs-repl app

… upon entering that command from a terminal session (in the guestbook directory). the REPL seems to start correctly, however it becomes effectively unusable due to the repeated DEBUG level log message:

[XNIO-1 I/O-4] DEBUG io.undertow.websockets.core.request - UT025003: Decoding WebSocket Frame with opCode 1

Other than that I believe, everything seems to be running correctly. For example I can get a JS Alert to appear on the targeted browser by typing into the REPL
(js/alert "Hello")
The repeated DEBUG message makes it inconvenient working with the REPL, and I certainly would benefit from understanding how to properly configure the logging that I am seeing. I is not at al clear to me where I would find the logging configuration in the current set-up I have (I have followed the steps described in the book up to this point)

Thanks for any advice!