With its latest beta release, the Mozilla Foundation has taken a step further toward making click-to-run the default behavior for all plugins in Firefox.
"Outdated plugins are a big source of security vulnerabilities so this feature will ensure users are safe and Firefox runs smoothly," the Firefox team said in a blog post on Thursday.
Under the new system, instead of automatically running plugins when a page opens, Firefox will replace that content with boxes warning the user that the required plugins may be vulnerable to exploits. The content will only be displayed if the user explicitly activates the plugins – each a potential infection vector for malware.
The one exception to this new policy is Adobe's Flash Player plugin, which Mozilla has determined is used by too many websites to fall under the manual activation requirement. But Firefox users will only be able to dodge the click-to-run warning if the version of the Flash plugin they have installed is the latest one.
"Users with older versions of Flash that are known to be insecure will see the click-to-activate user interface and will be prompted to upgrade to the latest version," Mozilla's Benjamin Smedberg wrote in September. "Our security and plugin teams work closely with Adobe to make sure that Firefox users are protected from instability or security issues in the Flash plugin."
This isn't the first time Mozilla has implemented such security measures. With the release of Firefox 24 in September, Mozilla marked all versions of the Oracle Java plugin as "unsafe," including the latest build – a decision that was eventually rescinded amid widespread uproar from the Java-using community.
Mozilla isn't alone in being concerned about the potential security threats posed by plugins, either. Google's approach to locking down Flash in its Chrome browser is to bundle the plugin inside the browser itself and update it automatically, so that users can't run an old version of the plugin even if they want to.
Mozilla has been testing its click-to-play plugin system in its experimental Firefox builds since January. With its release into the beta channel on Friday, the technology moves a major step closer to becoming part of the mainstream Firefox product.
The latest mainstream version of the browser, Firefox 25, was released on Tuesday with a smattering of new features, most notably support for the Web Audio API and blocking of insecure content on encrypted web pages.
If all goes according to plan, Firefox 26 is expected to move from beta into public release status with click-to-run plugins enabled by default during the week of December 10. ®