Goal: sweep the mouse across the box for ~1s, then click the green button. Page measures the inter-event timestamp distribution of mousemove events. Real pointing devices fire at ~60–250 Hz (median Δt 4–18ms). Bridges that flood synthetic moves on a tight for-loop or setTimeout(...,1) produce a degenerate distribution (most Δt < 2ms, or all Δt identical, or median > 50ms with no jitter).