title: How Prevent Multiple Copies Of React from Loading?
body: <p>In my previous Meteor app, using browserify, and React, all was working until I switched to <a href="https://github.com/jedwards1211/meteor-webpack-react" rel="noreferrer">meteor webpack</a>.</p>
  
  <p>I use <a href="https://github.com/JedWatson/react-select/" rel="noreferrer">react-select</a> in my Meteor apps and it worked great but with browserify I could prevent multiple copies of react from loading which prevents this error I'm now having:</p>
  
  <pre>
  Error: Invariant Violation: addComponentAsRefTo(...): Only a ReactOwner can have refs. You might be adding a ref to a component that was not created inside a component's `render` method, or you have multiple copies of React loaded (details: https://fb.me/react-refs-must-have-owner).
  </pre>
  
  <p>My package.json look this:</p>
  
  <pre><code>...
  
  "dependencies": {
      "classnames": "^2.1.3",
      "lodash": "^3.10.0",
      "react": "^0.14.6",
      "react-dom": "^0.14.6",
      "react-mixin": "^2.0.1",
      "react-select": "^1.0.0-beta8"
    },
  
  ...
  </code></pre>
  
  <p>Is there a configuration in webpack I could use something call externals? Not fully sure what that means but a comment said to use:</p>
  
  <pre><code>externals: {
    'react': 'React',
    'react-dom': 'ReactDOM'
  }
  </code></pre>