The 16.5.0 package released to unpkg currently has the production/profiling variant present for cjs builds but there is no equivalent for umd builds. 

i.e. There is the file https://unpkg.com/react@16.5.0/cjs/react.profiling.min.js but there is no https://unpkg.com/react@16.5.0/umd/react.profiling.min.js

It would be great if a future release had the profiling variant packaged as umd as well.

Also thanks for the awesome framework!
return 'react/src/forks/ReactCurrentOwner.www.js';
      default:
        return null;
    }
  },
  
  'shared/invokeGuardedCallbackImpl': (bundleType, entry) => {
    switch (bundleType) {
      case FB_WWW_DEV:
      case FB_WWW_PROD:
      case FB_WWW_PROFILING:
        return 'shared/forks/invokeGuardedCallbackImpl.www.js';
      default:
        return null;
    }
  },
  
  'react-reconciler/src/ReactFiberErrorDialog': (bundleType, entry) => {
    switch (bundleType) {
      case FB_WWW_DEV:
      case FB_WWW_PROD:
      case FB_WWW_PROFILING:
        
        return 'react-reconciler/src/forks/ReactFiberErrorDialog.www.js';
      case RN_OSS_DEV:
      case RN_OSS_PROD:
      case RN_OSS_PROFILING:
      case RN_FB_DEV:
      case RN_FB_PROD:
      case RN_FB_PROFILING: