title: TypeError: Merging undefined is not supported
body: <p>I got this error when running <code>$ quasar dev</code> on my Vue project</p>
  <pre><code>~/project/node_modules/webpack-merge/dist/index.js:63
              throw new TypeError(&quot;Merging undefined is not supported&quot;);
                    ^
  
  [  TypeError: Merging undefined is not supported
  
    - index.js:63 mergeWithOptions
      [project]/[webpack-merge]/dist/index.js:63:19
  
    - index.js:52 merge
      [project]/[webpack-merge]/dist/index.js:52:35
  
    - quasar-conf-file.js:392 QuasarConfFile.compile
      [project]/[@quasar]/app/lib/quasar-conf-file.js:392:29
  
    - task_queues:96 processTicksAndRejections
      node:internal/process/task_queues:96:5
  
    - quasar-dev:237 async goLive
      [project]/[@quasar]/app/bin/quasar-dev:237:3
  
  ]
  </code></pre>