这个是自定义js

let oldFavicons = document.querySelectorAll('link[rel="shortcut icon"]');
oldFavicons.forEach((favicon) => favicon.remove());
let newFavicon = document.createElement('link');
newFavicon.rel = 'shortcut icon';
newFavicon.href = 'https://github.com/favicon.ico';
document.head.appendChild(newFavicon);

因为这个只能改网站的