What OS are you using and where are you seeing this?
I see it on the browser console due to an otherwise white screen, and Ubuntu 22.04.1
I have never in my life seen a webapp that cares about the operating system
It's because I wrote this app with cross platform software targeting mobile users. Web was an afterthought, so probably one of the packages isn't compatible with web. I put it there mainly for demo purposes. You'll have better success using it on your phone.