function getDevServer(): DevServerInfo {
  if (_cachedDevServerURL === undefined) {
    const match = SourceCode.scriptURL && SourceCode.scriptURL.match(/^https?:\/\/.*?\//);
    _cachedDevServerURL = match ? match[0] : null;
  }

  return {
    url: _cachedDevServerURL || FALLBACK,
    bundleLoadedFromServer: _cachedDevServerURL !== null,
  };
}
Many RN development tools rely on the development server (packager) running
@return URL to packager with trailing slash