VS emulator for Android stops responding to keyboard
The bug also occurs when you hit Win + R. My thesis is, that you switch focus in the emulator.
To get it to work again, simply mouse click a editbox or anything that gives your app focus again and hit win. Windows now opens start menu. Click in the emulator, and you can type again.
I submitted the bug to MS.
Another possibility is that the emulator thinks the Alt key is pressed, hit Alt to release it.
Also if keyboard is disabled we can enable the keyboard in the emulator by:
press the PAGE UP key or press the PAUSE/BREAK key.