Simon Willison’s Weblog

Timing and Synchronization in JavaScript. Comprehensive overview of how browsers (Opera in particular) load scripts and queue events, with suggestions for best practices.

Posted 30th April 2007 at 2:24 pm

Recent articles

V&A East Storehouse and Operation Mincemeat in London - 27th August 2025
The Summer of Johann: prompt injections as far as the eye can see - 15th August 2025
Open weight LLMs exhibit inconsistent performance across providers - 15th August 2025

browsers 88 javascript 718 opera 31 timing 1

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