You may have been redirected from a service that carried a proof of concept demonstration involving a potential web application security weakness, to illustrate how such scenarios work in practice.
xs.je provides a pocket‑sized ("extra small") URL for times when every byte counts. Read "xs." as "access point", and "xs" as both "access" and "cross‑side" - a quiet nod to XSS.
Cross‑Site Scripting (XSS) is a common security vulnerability allowing potentially malicious script code to be injected into otherwise trusted websites. Those scripts then run in your browser and can produce unexpected behaviour.
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