Seriously though, there is a hell of a lot to this thing and pretty much zero documentation. You can actually view the code that gets locally cached in /sys. It is possible to edit the system's code, but you need to have root permissions to do that.

The easiest way to get biofeedback from the bare desktop is to add the hotkey_apps parameter to the url like this:

https://yabbos.xyz/desk?hotkey_apps=TextEdit,Arcade,Synth,Fa...

Then you just press Ctrl+Alt+[1-9], where the number depends on the position in the list of apps, so Ctrl+Alt+1 opens the TextEdit app, etc. You can save files in TextEdit with Alt+s. The desktop currently uses the /tmp folder. You can always pop open a terminal with Alt+t.