How to Disable Java in Firefox
Oracle's Java scripting language has been the target of quite a few security attacks and currently (1/12/2013) it is vulnerable to a rather serious kind of attack. In fact, the United States Department of Homeland Security is warning people to disable it. So...here's how you can disable Java in Mozilla's Firefox browser:
Open Firefox (naturally)
Click the Firefox button at the top left corner of the browser.
Click the Add-ons option from the menu.
Find the Java plugin on the list and click the button to the right it that reads "Disable". If the button says "Enable" then it's already disabled.
It may be that you'll find important
sites for you that won't work with Java disabled. If that happens,
you'll probably have to re-enable Java by following the steps above and
re-enabling. If you DON'T have a problem with sites, however, you're
probably going to be safer in the long run by just leaving Java disabled
You may even want to consider uninstalling Java from your machine entirely if you determine you don't need it.
To uninstall Java from your Windows machine go to Control Panel find "Add/Remove Programs" (or click "Uninstall a program" on newer versions of Windows) and find "Java" on the program list. Select it and click "Uninstall".