What does a link preview prove?¶

A link preview shows that a messaging system produced or displayed summary material for a URL. It can preserve how a destination was represented, but it does not by itself prove that a person visited the page.

Preview generation involves a separate retrieval¶

When a URL is composed, sent, received or displayed, the sender's device, recipient's device or a provider-side service may fetch page metadata. The resulting title, description and image can be stored with the message even if nobody follows the link.

The visible text, encoded URL, preview target and eventual destination can differ. Shorteners and redirects may lead elsewhere, while a web page can change after the preview was created. Preserve the full URL and preview as separate artefacts.

Prove access from access records¶

Record the message and account identifiers, time, displayed and underlying URLs, preview image and any redirect information. Avoid opening a suspicious or operationally sensitive link from an evidential device merely to inspect it; preserve and examine it through an appropriate controlled method.

Browser history, application logs, DNS or network records and destination-side records may support an actual visit. Their times and device associations still need interpretation. As with an automatic media preview, system processing is not equivalent to human awareness.