Simon Willison’s Weblog

Deconstructing Facebook Beacon JavaScript. How Facebook’s new Beacon service (also known as “Facebook ruined Christmas”) actually works.

Posted 25th November 2007 at 9:20 pm

Recent articles

JustHTML is a fascinating example of vibe engineering in action - 14th December 2025
OpenAI are quietly adopting skills, now available in ChatGPT and Codex CLI - 12th December 2025
GPT-5.2 - 11th December 2025

beacon 1 facebook 117 javascript 727 privacy 64

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