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

ChatGPT agent's user-agent - 4th August 2025
The ChatGPT sharing dialog demonstrates how difficult it is to design privacy preferences - 3rd August 2025
Reverse engineering some updates to Claude - 31st July 2025

css 229 documentation 54 extensions 5 firebug 22 firefox 90 firescope 1 html 88 reference 1 sitepoint 13

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