The latest version of angular is only setup for evergreen browsers by default…
The current setup is for so-called “evergreen” browsers; the last versions of browsers that automatically update themselves. This includes Safari >= 10, Chrome >= 55 (including Opera), Edge >= 13 on the desktop, and iOS 10 and Chrome on mobile.
This also includes firefox, although not mentioned.
See here for more information on browser support along with a list of suggested polyfills for specific browsers. https://angular.io/guide/browser-support#polyfill-libs
This means that you manually have to enable the correct polyfills to get Angular working in IE11 and below.
To achieve this, go into polyfills.ts (in the src folder by default) and just uncomment the following imports:
/***************************************************************************************************
* BROWSER POLYFILLS
*/
/** IE9, IE10 and IE11 requires all of the following polyfills. **/
import 'core-js/es6/symbol';
import 'core-js/es6/object';
import 'core-js/es6/function';
import 'core-js/es6/parse-int';
import 'core-js/es6/parse-float';
import 'core-js/es6/number';
import 'core-js/es6/math';
import 'core-js/es6/string';
import 'core-js/es6/date';
import 'core-js/es6/array';
import 'core-js/es6/regexp';
import 'core-js/es6/map';
import 'core-js/es6/set';
Note that the comment is literally in the file, so this is easy to find.
If you are still having issues, you can downgrade the target property to es5 in tsconfig.json as @MikeDub suggested. What this does is change the compilation output of any es6 definitions to es5 definitions. For example, fat arrow functions (()=>{}) will be compiled to anonymous functions (function(){}). You can find a list of es6 supported browsers here.
Notes
• I was asked in the comments by @jackOfAll whether IE11 polyfills are loaded even if the user is in an evergreen browser which doesn’t need them. The answer is, yes they are! The inclusion of the IE11 polyfills will take your polyfill file from ~162KB to ~258KB as of Aug 8 ’17. I have invested in trying to solve this however it does not seem possible at this time.
• If you are getting errors in IE10 and below, go into you package.json and downgrade webpack-dev-server to 2.7.1 specifically. Versions higher than this no longer support “older” IE versions.