To disable the Java plugin in your Mozilla browser, open the Add-ons Manager, find the Java plugin entry as described above and then, depending on the browser version, click the "Disable" or "Never Activate" button.
Applies to Windows or Mac OS X 10.7.3 and above Starting in Java 7, the Java Control Panel includes the Security option, "Enable Java content in the browser", which is selected by default.
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On Mac OS X 10.7.3 (Lion) and above, Java 7 is available here or from this download page. (If you are looking for Java 6, see the Java 6 FAQ page).
You can also download an offline installer using the "JRE" download link on Oracle's Java SE Downloads. Even if you have a 64-bit operating system, you need the 32-bit (x86) Java download for 32-bit browsers.
See 64 bit builds for more information about 64-bit versions of Mozilla applications.
   Note: The Java Embedding Plugin has been bundled with Mac distributions of older Mozilla browsers, including Firefox 3.x and Sea Monkey 2.0.
In such cases, you can access the 32-bit Java Control Panel for Java 7 by running C:\Program Files (x86)\Java\jre7\bin\(press "Windows key R" to open the Run box).