Make the site have a rainbow background
<all_urls>
(function() {
let hue = 0;
(function rainbowBackground() {
document.body.style.backgroundColor = `hsl(${hue}, 100%, 50%)`;
hue = (hue + 1) % 360; // Loop back after reaching 360
requestAnimationFrame(rainbowBackground);
})();
})();Install requires the InjectJS Chrome extension. Scripts run only on sites matching the pattern above. Review code before installing any community script.