Simon Willison’s Weblog

FireScope. Neat little Firefox / Firebug extension which adds a “Reference” tab showing documentation for the selected element from the comprehensive SitePoint Reference site.

Posted 5th February 2009 at 10:51 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

css 230 documentation 54 extensions 5 firebug 22 firefox 90 firescope 1 html 93 reference 1 sitepoint 13

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