There might be a problem with the project dependency tree. It is likely not a bug in Create React App, but something you need to fix locally.

/* Answer to: "There might be a problem with the project dependency tree. It is likely not a bug in Create React App, but something you need to fix locally." */

/*
  Go to your "package.json" file.
  Replace
*/
  "react-scripts": "<whatever-is-currently-here>",
/* with */
  "react-scripts": "1.1.4",
/*
  Then run npm install and after that npm start
*/

// first run in terminal:
 yarn add --dev dotenv
 
// create .env file in root directory 
// then add below line in the .env file
 SKIP_PREFLIGHT_CHECK=true