服务器端使用如下代码获取 userAgent 出错，获取到的 userAgent 中不包含 MicroMessenger。

Mozilla/5.0 (Linux; Android 9; SM-G9730 Build/PPR1.180610.011; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/66.0.3359.126 MQQBrowser/6.2 TBS/45031 Mobile Safari/537.36

Mozilla/5.0 (Linux; Android 9; Nokia 7 plus Build/PPR1.180610.011; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/66.0.3359.126 MQQBrowser/6.2 TBS/45031 Mobile Safari/537.36

req.headers['user-agent'].indexOf('MicroMessenger') != -1