"aurelia-polyfills" doesn't work (or we cannot import it correctly)

We are using Aurelia JS in our project. On IE11 we get error conntected to missing "includes" method: Object doesn't support property or method 'includes'

We've installed aurelia-polyfills plugin but it doens't work (or we use it in wrong way).

In main-webpack.js:

...
import 'aurelia-polyfills';
...

bootstrap(function (aurelia) {
    aurelia.use
        .standardConfiguration()
        .defaultResources()
        .developmentLogging()
        ...
        .plugin(PLATFORM.moduleName('aurelia-polyfills'));

    aurelia.start().then(() => aurelia.setRoot(PLATFORM.moduleName('app-webpack'), document.body));
});

Our import statement is correct? Should we do it in the same file?