Chrome did it already, the new browser Edge never will support it and now also Firefox will cancel the plugin interface NPAPI by the end of next year.
I'm really looking forward to Windchill 11 and I hope PTC will present a HTML5 Creo View and the end of the Java Applets...
https://blog.mozilla.org/futurereleases/2015/10/08/npapi-plugins-in-firefox/