open-browser-webpack-plugin | Opens a new browser tab when Webpack | Web Framework library

You put request in the externals section. This means that webpack is assuming that request is included elsewhere, so it doesn't include it in your bundle. Taking request out of the externals should fix the issue.

Go to your webpack.dev.config.js and look for entry: []. Just add your runtime.js file there. Like below

According to the docs

The reducer is a pure function that takes the previous state and an action, and returns the next state.

You can then see that it's because you are breaking out of your switch statement rather than returning the new state in DashboardReducer.js. It should instead look something like this:

I do believe that this error was caused because I had two versions of Webpack installed for my project. This would make sense from perspective that the error occurred in one environment and not others. Perhaps the npm dependency tree was different and an older version of Webpack was being used for some reason.

There was an npm package: webpack-rev-replace-plugin that had a Webpack v1.5 dependency. I was using Webpack v4.16. Once I removed the webpack-rev-replace-plugin and thus the older version of Webpack, I started getting a different error related to the uglifyjs-webpack-plugin, once I removed the uglifyjs-webpack-plugin and just used Webpacks defaults for minification etc, all was fine.

Solved this problem, by editing webpack config file. There I turned off opening browser after build finishes, by commenting "New OpenBrowserPlugin" like below:

Well, clearly I didn't search long enough.. Impatient me..

My visual studio didn't show any intellisense on the error, but after some trying I only had to update my react-router to a newer version ;)

I do not know, but it looks like you have error in your code, you try to import switch and route from wrong package. React-router - 3 version, and react-router-dom - 4 version, so your code should look like below;

Seems you're not adding jQuery to your pack. Go make a new file and save it locally for jQuery. Import it before your bootstrap.js file.

I changed my webpack.prod.js