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

First impressions of Claude Cowork, Anthropic's general agent - 12th January 2026
My answers to the questions I posed about porting open source code with LLMs - 11th January 2026
Fly's new Sprites.dev addresses both developer sandboxes and API sandboxes at the same time - 9th January 2026

css 231 documentation 54 extensions 5 firebug 22 firefox 90 firescope 1 html 94 reference 1 sitepoint 13

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