一个有意思的说法： Lie-fi，说谎的 Wi-Fi，也就是“连了一个假 Wi-Fi”。

Sam Dutton, Developer Advocate for Google Chrome ：

Lie-fi can actually be worse than offline; at least if a device is
definitely offline, your JavaScript can take appropriate evasive
action.

连上的 Wi-Fi 处于弱连接状态，弱网络下导致实际无法上网，而此时系统以为有网络不会切换至离线模式，最糟的用户体验。

navigator.onLine 本身的不可靠，只能自行检测网络的真正连通状况（或设置超时）。

另外一个有意思的职位 Developer Advocate，或许叫“开发技术推广工程师”：

A developer advocate is someone who’s primary responsibility is to
make it easy for developers to use a platform.
via http://blog.phymata.com/2012/12/28/what-is-a-developer-advocate/

refer:
https://www.outsystems.com/blog/lie-fi.html
https://developers.google.com/web/fundamentals/performance/poor-connectivity/?hl=zh-cn