Simon Willison’s Weblog

Opera and the Acid3 Test. Screenshot shows 100/100 (live code or it didn’t happen!)—Opera’s codebase must be in extremely good shape to fix so many issues so quickly.

Posted 26th March 2008 at 10:47 pm

Recent articles

OpenAI are quietly adopting skills, now available in ChatGPT and Codex CLI - 12th December 2025
GPT-5.2 - 11th December 2025
Useful patterns for building HTML tools - 10th December 2025

acid3 5 browsers 93 opera 31 web-standards 47

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