About the Starfield effect
The Starfield background scatters stars across the canvas using a deterministic hash of each cell's coordinates, so the sky layout is stable from frame to frame instead of flickering randomly. About one and a half percent of cells become bright stars that twinkle between * and + as a sine wave sweeps through them, and a further sprinkling of cells hold faint dots that never move. The result is a quiet night sky with a gentle shimmer, closer to looking up on a clear night than to the hyperspace streaks of space games. Because the pattern depends only on position, resizing the window reveals more sky rather than reshuffling it. White or cyan stars look natural; amber reads as a vintage observatory printout. It is one of the lightest effects to render, so it is a safe choice for always-on displays and low-power laptops.