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

V&A East Storehouse and Operation Mincemeat in London - 27th August 2025
The Summer of Johann: prompt injections as far as the eye can see - 15th August 2025
Open weight LLMs exhibit inconsistent performance across providers - 15th August 2025

firefox 90 java 89 javascript 719 mark-pilgrim 85 performance 92

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