[LAD] Linux-show-player dependencies?

I noticed there's a new release of linux-show-player, version 0.5. I'm a co-maintainer of its AUR package [1] and I wanted to update it and I noticed that a few additional dependencies where added to the setup.py, namely JACK-Client and scandir. The latter isn't relevant for Arch Linux, since it is already on Python 3.6, which has scandir included. But there doesn't seem to be an AUR package for JACK-Client yet, so I tried running linux-show-player without it and to my surprise it seemed work perfectly and there isn't even an option to select JACK as the output in the preferences. So my question is: is the dependency on JACK-Client optional? Where is it used? Chris [1] https://aur.archlinux.org/packages/linux-show-player/