Firefox has decided to stop supporting plugins based on the Netscape Plugin Application Programming Interface (NPAPI) by the end of 2016.
Ironically, because much web-content still persists in the format, Flash will still be supported.
In its statement, Mozilla said:
"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."
No guidance was provided for developers of document technologies such as PDF.