Light Table editor can't eval defprotocol in cljs source file

Question

I use Windows 10, first I create project via Lein new mies

then I add some content in core.cljs

(+ 1 2)

(defprotocol MaybeMutable
  (mutable? [this] "Returns true if the value is mutable."))

I select code above and hit ctrl + enter to eval the code, (+ 1 2) evals correct, but error occurs in defprotocol

clojure.lang.ExceptionInfo: Can't change/establish root binding of: unchecked-if with set