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

Introducing Showboat and Rodney, so agents can demo what they’ve built - 10th February 2026
How StrongDM's AI team build serious software without even looking at the code - 7th February 2026
Running Pydantic's Monty Rust sandboxed Python subset in WebAssembly - 6th February 2026

browsers 97 javascript 740 opera 31 timing 1

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