const EXTRA_REFILL: f64 = _; // 0.03125f64Expand description
The share of an extra frame each period adds to that reserve: the sustained rate rises above the configured one by at most this share. A slower refill leaves a source at the cadence locked behind a keystroke’s extra frame for longer (a 60 Hz animation with a keystroke every 0.7 s waited 7.6 ms a frame at the median at 1/64, 12.5 ms at 1/128).