Simon Willison’s Weblog

Acid3 is out. The third Acid test, again compiled by Ian Hickson. This one viciously tests DOM Scripting standards compliance and currently exposes flaws in every browser.

Posted 5th March 2008 at 12:34 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

acid3 5 ian-hickson 22 javascript 718 standards 32 web-standards-project 8

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