title: Error: Cannot find module 'webpack-cli/bin/config-yargs' with webpack-cli 4.2.0
body: <p>When I try to run webpack-dev-server it gives the error.</p>
  <pre><code>Error: Cannot find module 'webpack-cli/bin/config-yargs'
  </code></pre>
  <p>I looked around and found that you had to change the script to &quot;webpack serve&quot; and did that but then it gives me the following:</p>
  <p>**[webpack-cli] Invalid configuration object. Webpack has been initialized using a configuration object that does not match the API schema.</p>
  <ul>
  <li>configuration.devtool should match pattern &quot;^(inline-|hidden-|eval-)?(nosources-)?(cheap-(module-)?)?source-map$&quot;. BREAKING CHANGE since webpack 5: The devtool option is more strict.    Please strictly follow the order of the keywords in the pattern.**</li>
  </ul>
  <p>My system is Windows 10 Pro and the versions are the following:</p>
  <ul>
  <li>webpack: 5.6.0</li>
  <li>webpack-cli: 4.2.0</li>
  <li>webpack-dev-server: 3.11.0</li>
  </ul>
  <p>I've also tried including &quot;inline: false&quot; into the devServer object in webpack.config.js but to no avail.</p>