Firefox 26 Arrives with Click to Play for Java
First and foremost, the Click to Play revamp was supposed to be for all versions of all plugins, except the latest release of Flash. Unfortunately, Mozilla has pushed back this change and decided to focus on just Java.
In short, the feature means Firefox now only loads Java plugins when users click to interact with them. Previously, Firefox would automatically load Java whenever a site requested it, unless Mozilla had blocked it for security reasons (the company already blocks old versions of Java, Silverlight, and Flash).
Now, when a site tries to use Java, the user can choose whether to enable the plugin on that site. Firefox will only load it when you take the action of clicking to make it play. Alternatively, you can also configure Click to Play so that it always runs plugins on a particular website.