Detection is hard (impossible for arbitrary JS) if the cookie isn't physically stored somewhere (at least in memory). That said, I think cookie auto deletion b

Detection is hard (impossible for arbitrary JS) if the cookie isn't physically stored somewhere (at least in memory). That said, I think cookie auto deletion basically satisfies that use case? I personally have cookies set to wipe when I close my browser, and I close my browser fairly frequently. That's not quite as often as you're suggesting though.