Answers for "regeneratorruntime is not defined heroku"

regeneratorruntime is not defined

// In package.json add 
{
...
  "browserslist": {
    "production": [
      ">0.2%",
      "not dead",
      "not op_mini all"
    ],
    "development": [
      "last 1 chrome version",
      "last 1 firefox version",
      "last 1 safari version"
    ]
  }
  ...