Now Playing widget not functioning off wifi - normal?

While using the BTT touch bar Now Playing widget for iTunes, I find that it does not display the information when I am offline (= wifi turned off). Noticed this during a recent flight in airplane mode, and tested with wifi on/off again after landing.

I don't know if this is how it is supposed to work, so maybe not a bug, but it would definitely be useful if there was a way I could use the widget offline as well, as me playing music doesn't have much to do with me being online. Thanks for any help.

I'm on a MacBook Pro 13" 2018, High Sierra, BTT 2.660 (968).