Simon Willison’s Weblog

New features for extension developers in Firefox 1.5. We’re going to see some amazing innovation in extensions in the next few months.

Posted 4th November 2005 at 11:29 am

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

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