Simon Willison’s Weblog

15th March 2009 - Link Blog

Understanding Bidirectional (BIDI) Text in Unicode. It turns out you need to sanitise user input to ensure there are no unicode characters that switch your site’s regular text to RTL.

Posted 15th March 2009 at 4:37 am

Recent articles

Some thoughts on the Navier–Stokes Millennium Prize Problem - 8th September 2026
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OpenAI's rogue agents were caught communicating via public wikis - 4th September 2026

This is a link post by Simon Willison, posted on 15th March 2009.

bidi 1 cal-henderson 7 filtering 2 security 630 unicode 35 userinput 1

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