code: function openBrowser(url) {
    const { action, value } = getBrowserEnv();
    switch (action) {
      case Actions.NONE:
        // Special case: BROWSER="none" will prevent opening completely.
        return false;
      case Actions.SCRIPT:
        return executeNodeScript(value, url);
      case Actions.BROWSER:
        return startBrowserProcess(value, url);
      default:
        throw new Error('Not implemented.');
    }
  }
docs: Reads the BROWSER environment variable and decides what to do with it. Returns
  true if it opened a browser or ran a node.js script, otherwise false.