it’s because a small bug in new image
in the test, we found a small bug, that is the video_fullscreen in retroarch.cfg can not be false, some emulators will not be able to fill the screen.
In /home/cpi/.config/retroarch/retroarch.cfg
line 2
change video_fullscreen = "false" to video_fullscreen = "true"
ssh into gs should get the job done
sorry for the bug