https://blog.wongcw.com/2021/01/08/%e9%a6%ac%e6%96%af%e5%85%8b%e4%b8%8d%e6%bb%bfwhatsapp%e6%96%b0%e6%94%bf%e7%ad%96signal%e6%88%96%e6%88%90%e6%9c%80%e5%a4%a7%e8%b4%8f%e5%ae%b6/