Mozilla has been steadily improving the Web platform to support features that were once only available via NPAPI plugins.

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Mozilla intends to remove support for most NPAPI plugins in Firefox by the end of 2016. Firefox began this process several years ago with manual plugin activation, allowing users to activate plugins only when they were necessary. This decision mirrors actions by other modern browsers, such as Google Chrome and Microsoft Edge, which have already removed support for legacy plugins. Moreover, since new Firefox platforms do not have to support an existing ecosystem of users and plugins, new platforms such as 64-bit Firefox for Windows will launch without plugin support.

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Websites and publishers which currently use plugins such as Silverlight or Java should accelerate their transition to Web technologies. The Web platform is powerful and can usually do everything that a plugin can do. In the rare cases where a site needs to extend Web technologies, the recommended solution is to develop the additional features as a Firefox add-on. Site maintainers should prepare for plugins to stop working in all versions of Firefox by the end of 2016.

Mozilla continues to work with the Oracle Java Platform Group to ensure a smooth transition for those web sites that use Java. More information from Oracle about Java transition plans can be found in a post from the Oracle team. Oracle recommends that sites currently using Java applets consider switching to plugin-free solutions such as Java Web Start.

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