For few months has the Microsoft team the answer to Visual Studio User Voice case .
Shortly described :
While Microsoft continues to support Silverlight, and remains committed to doing so into 2021, there will be no new development work except security fixes and high-priority reliability fixes.
Silverlight out-of-browser apps will work in Windows 10. Silverlight controls and apps will continue to work in Internet Explorer until October 12, 2021, on down-level browsers and on the desktop.
Our support lifecycle policy for Silverlight remains unchanged:
For future development, we recommend modernizing Silverlight applications to HTML5 solutions which provide broader reach across platforms and browsers. In addition to the solutions listed in the blog post above, there is a free .NET Technology Guide eBook to help with migration planning located at:http://download.microsoft.com/download/1/6/E/16E9FC39-0D61-4DB8-AADE-9F6950B8BF49/Microsoft_Press_eBook_NET_Technology_Guide_for_Business_Applications.pdf