https://sansec.io/research/polyfill-supply-chain-attack https://news.ycombinator.com/item?id=40791829 没有必要应当尽快撤掉，仍需继续使用尽量自行托管，或者考虑 cdnjs.cloudflare.com/polyfill 、polyfill-fastly.io 和 polyfill.alicdn.com
