How to Add FPS Counter on Android TV Not in Game Mode

In Android, you can enable native display of frame rate in developer mode, but it will only work when the game is running. But what if you want to see the counter all the time? I'll start with the bad news: there is no easy way to solve this problem. Even if you find third-party apps for counting fepis, they will not show the real value. Instead, something close to reality will be displayed (at best). To add the counter, you will need ADB and, p…