We merged https://gerrit.wikimedia.org/r/119898 on Thursday and I tested that it worked, but the old JS for the site is still cached for logged-out users so it appears at first glance to not be working. ?debug=true revealed the ?debug=truth.
Probably there should be a part of the code update job that touches any modified JS files, so the cache is invalidated. Else the cache should be explicitly invalidated on meaningful code update.
Or, at the very least, please invalidate the cache so we can actually test this feature. :)