new terminal window interaction frozen on idle

[JasperTeng]

I am able to open terminal in a window (i.e.: ctrl+alt+shift+`).
However if i leave it idle for sometime to focus on applications not related to code server (e.g.: notepad), then focus back to the new terminal window. Every keystroke enter does not echo and screen is basically frozen. But if i focus back to the code server primary window then back to the new terminal, every keystroke i entered previously is now shown. Why is this so? 🤔