Webpack fails to load bootstrap v4.0.0-beta

After several tests this is my conclusion for running bootstrap v4.0.0-beta with Webpack so you will need to manually install jquery and popper.js, it will not be installed by bootstrap as dependencies anymore. It will not work without jquery and the dropdowns/popups will not work without popper.js so:

npm install bootstrap@4.0.0-beta -D
npm install jquery -D
npm install popper.js -D

I ended up editing the post, because it was pointed out that popper and popper.js are 2 different libraries(which I didn’t knew) I was trying to install popper.js with npm install popper and therefore I had the issue… so installing it with npm install popper.js will install the latest version of it (and the right library).
Then you have to change in the webpack.config.js just as mentioned in https://getbootstrap.com/docs/4.0/getting-started/webpack/

plugins: [
    ...
      new webpack.ProvidePlugin({
        $: 'jquery',
        jQuery: 'jquery',
        'window.jQuery': 'jquery',
        Popper: ['popper.js', 'default'],            
        ...
      })
    ...
  ]

Then the rest of the config should be the same as it was for v4 alpha. Anyway this is what I found out after struggling with this for a while. Hope it will help someone.