Strange behavoiur with google chrome and FPS
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I have coded a little engine to display 5 sprites using javascript in Canvas2D. Everything works fine and is completely optimised.

The FPS fluctuates between 30 and 60 - but the interesting thing is, it says on a constant 60 fps when the google javascript console is open!

Any body else experiencing this?

n.b. I am using requestAnimationFrame