Polyfill claims it has been 'defamed', returns after domain shut down

Executive summary: A compromised third‑party CDN (polyfill.io) was used to deliver malicious JavaScript to websites embedding its scripts, redirecting visitors (notably mobile users) to fraudulent sites and impacting over 100,000 websites; Cloudflare and Google have raised concerns and providers and researchers recommend removing cdn.polyfill.io (and the relaunched polyfill.com) from sites and replacing it with trusted alternatives.