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

Large Language Models can run tools in your terminal with LLM 0.26 - 27th May 2025
Highlights from the Claude 4 system prompt - 25th May 2025
Live blog: Claude 4 launch at Code with Claude - 22nd May 2025

opera 31 javascript 708 timing 1 browsers 83

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