For those who are experiecing a missing mouse cursor / pointer during Steam Link or Steam in-home-streaming, be aware that this is caused by a “glitch” of Windows 10. If you are experiencing this, you most likely have removed the keyboard and mouse from your Steam Host (the computer running the game) to use on the Steam Client (the computer / Steam Link which will stream the game) – and thats the source of the problem. Windows 10 hides the mouse cursor / pointer if it doesn’t detect any mouse input on the host system. Therefore, the streaming device will not show the mouse cursor either.
The solution is simple: just connect a spare mouse to the host and it will show up on the streaming device! Have fun!