How do I get the FPS in V3.0?
It was OS.get_frames_per_second() in V2.1.4
You can use Performance.get_monitor(0)
Small addendum -- you should probably use Performance.TIME_FPS, not 0, for that lone argument.
why ? Performance.TIME_FPS is equal to 0.
Note that this answer works the same but will lead to more readable code.
Yours works as well!