I noticed that your game runs at 60 fps in smaller window, and when it's maximized, the fps drops down to 20.
There are a few things:
1. Larger the canvas is, more it consumes to draw things, then the frame rate drops, it's not relevant to your settings, the fps in settings just fix the maximum frame rate.
2. There are difference between navigators, as we used
requestAnimationFrame function, some navigator will reduce the frame rate when the CPU/Memory consummation is big.
3. I noticed in your picture, the main loop of your game takes only 0.001 second per frame(the second line in stats). That means the main loop doesn't consume much, so it's mainly related to your canvas size, not your game logic.