title: Create-React-App: ESlint error while deployment on local machine
body: <p>I am using create-react-app (React v16.12.0). I am getting following error when I run <code>'npm start'</code> on mac. </p>
  
  <pre><code>[1] There might be a problem with the project dependency tree.
  [1] It is likely not a bug in Create React App, but something you need to fix locally.
  [1]
  [1] The react-scripts package provided by Create React App requires a dependency:
  [1]
  [1]   "eslint": "^6.6.0"
  [1]
  [1] Don't try to install it manually: your package manager does it automatically.
  [1] However, a different version of eslint was detected higher up in the tree:
  [1]
  [1]   /Users/abz/node_modules/eslint (version: 6.5.1)
  [1]
  [1] Manually installing incompatible versions is known to cause hard-to-debug issues.
  [1]
  [1] If you would prefer to ignore this check, add SKIP_PREFLIGHT_CHECK=true to an .env file in your project.
  [1] That will permanently disable this message but you might encounter other issues.
  [1]
  [1] To fix the dependency tree, try following the steps below in the exact order:
  [1]
  [1]   1. Delete package-lock.json (not package.json!) and/or yarn.lock in your project folder.
  [1]   2. Delete node_modules in your project folder.
  [1]   3. Remove "eslint" from dependencies and/or devDependencies in the package.json file in your project folder.
  [1]   4. Run npm install or yarn, depending on the package manager you use.
  [1]
  [1] In most cases, this should be enough to fix the problem.
  [1] If this has not helped, there are a few other things you can try:
  [1]
  [1]   5. If you used npm, install yarn (http://yarnpkg.com/) and repeat the above steps with it instead.
  [1]      This may help because npm has known issues with package hoisting which may get resolved in future versions.
  [1]
  [1]   6. Check if /Users/abz/node_modules/eslint is outside your project directory.
  [1]      For example, you might have accidentally installed something in your home folder.
  [1]
  [1]   7. Try running npm ls eslint in your project folder.
  [1]      This will tell you which other package (apart from the expected react-scripts) installed eslint.
  [1]
  [1] If nothing else helps, add SKIP_PREFLIGHT_CHECK=true to an .env file in your project.
  [1] That would permanently disable this preflight check in case you want to proceed anyway.
  [1]
  [1] P.S. We know this message is long but please read the steps above :-) We hope you find them helpful!
  [1]
  [1] react-scripts start exited with code 1
  </code></pre>
  
  <p>I googled and found </p>
  
  <ol>
  <li><p>following solution suggested by many</p>
  
  <ul>
  <li>Delete the <code>eslint and babel-eslint</code> from <code>users/abz/node_modules/</code>folder     </li>
  <li>Delete <code>package.json-lock, node_modules</code> from local project </li>
  <li>Run <code>npm install</code> and <code>npm start</code></li>
  </ul>
  
  <p><strong>I tried it and this solution didn't work for me.</strong></p></li>
  <li><p>This issue can be mitigated by using</p>
  
  <pre><code>adding an `.env file` in root folder with statement `SKIP_PREFLIGHT_CHECK=true` 
  </code></pre>
  
  <p><strong>But, it is not the solution for this problem.</strong></p></li>
  </ol>
  
  <p>Any help?</p>