There is a failure to process {{(require 'cljs.js)}} when in an {{--init}} file for the browser REPL. I haven't found any other namespace that this fails with (for example, {{clojure.set}} doesn't exhibit this).
Repro:
`
(require 'cljs.js)
(prn cljs.js/empty-state)
`
$ clj -Srepro -m cljs.main -re browser -i foo.cljs -r
TypeError: undefined is not an object (evaluating 'cljs.js.empty_state')
cljs.user=>
It works fine with Node:
`
$ clj -Srepro -m cljs.main -re node -i foo.cljs -r
object[cljs$js$empty_state]
cljs.user=>
`