Simon Willison’s Weblog

ReferenceError: console is not defined. Since Firebug 1.2 you need to call window.loadFirebugConsole() in order for console.log and friends to work.

Posted 23rd December 2008 at 10:22 pm

Recent articles

GPT-5: Key characteristics, pricing and model card - 7th August 2025
OpenAI's new open weight (Apache 2) models are really good - 5th August 2025
ChatGPT agent's user-agent - 4th August 2025

debugging 35 firebug 22 firefox 90 javascript 718

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