Out of the box this plays Tobu Tobu Girl (a complete homebrew Game Boy game, MIT-licensed —
ours to host). Pick a system + choose a ROM file to play one of your own owned games; the file stays
in your browser, nothing is uploaded. The emulator cores (RetroArch, compiled to WebAssembly) are loaded
from the EmulatorJS CDN. To run heavier systems (N64/PS1) faster with threads, this site needs
cross-origin-isolation headers — see _headers and the study page.