Simon Willison’s Weblog

Magic properties make Firefox synchronously load the Java plugin. Even defining a function called sun() (or several other symbols) will trigger the Java VM to be loaded, dramatically hurting the performance of your page.

Posted 27th February 2009 at 4:03 pm

Recent articles

I think "agent" may finally have a widely enough agreed upon definition to be useful jargon now - 18th September 2025
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

firefox 90 java 89 javascript 722 mark-pilgrim 85 performance 92

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