I think you have talkback enabled
I would say this has something to do with a setting in accessibility or developer options.
You also have not specified the device, so there is the potential this is not an official GoogleTV device (NVIDIA shield, CCwGTV, baked into Sony, etc) and they may be using a different launcher
In case it’s not clear, I’m referring to that green rectangle on the Netflix card. This thing shows up everywhere on the UI (apps, settings, etc.)
Even in kids mode android have shortcuts for certain features I believe
Accessibility > TalkBack Off
Damn. I forget. I think it's down + home. Or down + back button
That’s an accessibility setting I think. My four year old enables that on occasion by accident