Simon Willison’s Weblog

The versioning switch is not a browser detect. PPK: “In other words, the versioning switch does not have any of the negative effects of a browser detect.”

Posted 22nd January 2008 at 4:34 pm

Recent articles

JustHTML is a fascinating example of vibe engineering in action - 14th December 2025
OpenAI are quietly adopting skills, now available in ChatGPT and Codex CLI - 12th December 2025
GPT-5.2 - 11th December 2025

browserdetect 1 browsers 93 doctypeswitching 2 ie8 25 internet-explorer 74 ppk 6 web-standards 47 xuacompatible 10

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