I thought they were only blocked and that you could click to play anyway: *[https://addons.mozilla.org/en-US/firefox/blocked/p412] How to unblock/block are mentioned here: [[Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems]] For linux it seems there is also a file that the preferences are stored and can be changed, but that is a way to change it without the interface and not user friendly [http://www.linuxquestions.org/questions/programming-9/java-preferences-where-are-they-stored-871479/] I am not sure why it stopped in newer versions of Firefox, but it may have to do with the blocked java version. I might also suggest to ask in the addons forum in addons.mozilla.org in stackoverflow where the community is a little more technical.