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

ChatGPT agent's user-agent - 4th August 2025
The ChatGPT sharing dialog demonstrates how difficult it is to design privacy preferences - 3rd August 2025
Reverse engineering some updates to Claude - 31st July 2025

firefox 90 java 89 javascript 717 mark-pilgrim 85 performance 92

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