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

My review of Claude's new Code Interpreter, released under a very confusing name - 9th September 2025
Recreating the Apollo AI adoption rate chart with GPT-5, Python and Pyodide - 9th September 2025
GPT-5 Thinking in ChatGPT (aka Research Goblin) is shockingly good at search - 6th September 2025

browsers 89 javascript 721 opera 31 timing 1

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