A practical, start-to-finish guide to making QR codes that cost nothing and keep working: picking the payload, keeping it short, editable codes without a redirect service, design that still scans, export sizes and the testing routine I run before anything goes to print.
CSRF exploits one browser behavior: cookies are attached automatically, no matter who initiated the request. Tokens work because an attacker can make your browser send a request but cannot read your page to find the token. Here is the whole mechanism, with working PHP.
Five filters with four options each is 1,024 combinations, and a crawler will try to find all of them. Here is how faceted navigation turns into an infinite space, why rel=next/prev is not the fix, and the three patterns that keep pagination crawlable without the explosion.