jsdelivr is a free CDN for NPM packages and also github repos. the site is loading an icon font ([email protected]) from it. it's pretty nice as far as free npm cdns go, i guess. they even add SRI hashes to the script tags and stuff they generate by default so they can't swap out the files to malicious versions later.
Very educational content as well, the section on how pseudoterminals can be used to build terminal emulators was good, and on how ssh creates a remote terminal connection.