At the time, advanced users Yandex Browser and other browsers based on the same engine the Chromium, mindful of the support NPAPI technology, which was essential in the development of browser plug-ins, among them the Unity Web Player, Flash Player, Java, and others. This software interface first appeared in 1995, and has since spread to almost all browsers.
However, more than one and a half years ago Chromium project decided to abandon the technology. In NPAPI Yandex Browser continued to work for another year, thus helping developers of games and applications based on NPAPI find a modern replacement. And NPAPI disabled in Yandex Browser definitively in June 2016.
Can I enable NPAPI in Yandex Browser?
Since the termination of support for ad Chromium NPAPI to disable it in Yandex Browser been several important developments. So, Unity + Java refused to support and further develop their products. Accordingly, leave the browser plug-ins that do not use the site, it is meaningless.
As was stated, " ... will not be the end of 2016 no widespread browser for Windows with support for an NPAPI ». The thing is that this technology is already obsolete, no longer meet the requirements of security and stability, as well as not very fast compared to other current solutions.
As a result, enable NPAPI by any means in the browser is not possible. NPAPI If you still need, you can use Internet Explorer on Windows, and Safari in Mac OS. However, there is no guarantee that tomorrow the developers of these browsers also decide to abandon outdated technology in favor of new and safer analogues.