Angular animation error on Safari for Windows

Running your Angular > v.4 app on Safari for Windows and you’re using Animations? You might run into a nasty surprise where your application hangs at startup with this cryptic message:

TypeError: 'undefined' is not a function (evaluating 'i(d)')

Due to the crappy support for DevTools in Safari on Windows, i could not get a a proper stack trace for the error so it took me a while to finally trace the error down to the import 'web-animations-js'; in polyfills.ts . Inspecting the source code, I was able to trace down the i in the error above to window.requestAnimationFrame . The whole error is because Safari for windows does not support this function. You could try and fix it by installing this polyfill.

yarn add raf
//or alternatively
npm install raf --save

Once that’s installed though, you’ll run into your next error:

TypeError: setting a property that has only a getter

This issue is documented in the web-animation-js library and has not been fixed yet and will not be from all indication. The JS engine for the current version of Safari on Windows is just too outdated to support newer features required to run Angular. Until it is upgraded, you should inform your users that the browser is not supported.