You can polyfill it in those browsers. Just use polyfill.io, or if you prefer, manually feature-detect it and if necessary load Github's fetch polyfill, which i

You can polyfill it in those browsers. Just use polyfill.io, or if you prefer, manually feature-detect it and if necessary load Github's fetch polyfill, which is good: https://github.com/github/fetch https://github.com/github/fetch