Simon Willison’s Weblog

viewport-preview (via) I built a tiny tool which lets you preview a URL in a bunch of different common browser viewport widths, using iframes.

Posted 26th July 2022 at 12 am

Recent articles

Deep Blue - 15th February 2026
The evolution of OpenAI's mission statement - 13th February 2026
Introducing Showboat and Rodney, so agents can demo what they’ve built - 10th February 2026

css 233 iframes 21 mobile 40 projects 519 testing 88

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