How to suppress warnings using webpack and post css
<p>How do I suppress warnings generated by webpack loading post css files?</p>

<p>Warning example:</p>

<pre><code>WARNING in ./~/css-loader!./~/postcss-loader!./src/components/Navigator/Navigator.css
postcss-custom-properties: C:\StackData\bd\src\components\Navigator\Navigator.css:33:9: variable '--active' is undefined and
 used without a fallback
</code></pre>

<p>My webpack config:</p>

<pre><code> module: {
    loaders: [
   ...
      {test: /\.css/, loader: 'style-loader!css-loader!postcss-loader'},
   ...
    ]
  },
  postcss: function () {
    return [precss, autoprefixer];
  }
</code></pre>