Let's assume that was "performed an illegal operation" which *is* a typical error message. (More information might be helpful.)

It may mean your browser tried to do something the operating system will not accept. It may mean something hardware related, but that is much less likely. It does not mean you need a new computer!

Can you cause this to happen repeatedly? Does the condition happen when you're not using the Web? Does it happen on other sites? Try running your browser with no other programs running and see if it can be made to happen. Visit other sites, does it happen there? What browser and browser version (click Help, then About).

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