it is a taiko player, but it is not done yet.
it only supports .osu file format for now.

place the audio in the left file input and the notechart/beatmap in the right file input. then click "go" to go.
reset will restart the map.
autoplay toggle will do what it says - toggle autoplay.
controls and resolution will have instructions with them.
to change the music volume press [-]/[+].
to change the offset, press [Shift] + [-]/[+].
fullscreen will fullscreen...

it runs like garbage on firefox/gecko-based browsers. use a chromium based browser (maybe ungoogled chromium? or vivaldi?).

click to play