RiverlineStrictly necessary
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Preferences
Local storage remembers table settings such as the four-colour deck, sounds, reduced motion and your preferred table layout. They contain no personal data and can be cleared from your browser at any time.
Analytics
Google Analytics (GA4) counts page views so we can see which pages are used. It is not loaded on the two pages you reach from an email link (resetting a password, confirming an address). It sets the _ga and _ga_* cookies, which carry a random identifier for your browser and last up to two years. Advertising features and personalisation signals are switched off, IP addresses are not stored by GA4, and nothing sent identifies your account. Vercel Analytics also counts page views and sets no cookie. You can block these with your browser or a content blocker; the site works without them.