How to make webpack-dev-server apply my changes?

Trying to use WP dev server. My config file is the folowing:

var path = require('path');

module.exports = {
  entry: './frontend/app.js',
  output: {
    path: __diame + '/build',
    filename: 'bundle.js'
},

watch: false,

watchOptions: {
  aggregateTimeout: 100
},

module: {
  loaders: [
    { test:  /.js$/, loader: 'babel'},
    { test: /.css$/, loader: 'style!css' },
    { test: /.html$/, loader: 'html'}
  ]
},
devServer: {
  host: 'localhost',
  port: 8080
},

exteals: {
  lodash: "_",
  jquery: "$"
},

resolveLoader: {
   root: path.join(__diame, 'node_modules')
}

};

i launch webpack with the command: webpack-dev-server --inline and then go to http://localhost:8080/webpack-dev-server/

So it opens fine, but when i make some changes, like alert("Done!"); --> alert("Donasdadae!"); page is being reloaded automatically, but i still see the 'old' alert: "Done!", so changes have not been applied(but the page is reloaded! it drives me crazy)

What can I do about it? Thx