Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature currently requires accessing the site using the built-in Safari browser.
If you are still using CentOS 7.9, it's time to convert to Alma 8 with the free centos2alma tool by Plesk or Plesk Migrator. Please let us know your experiences or concerns in this thread: CentOS2Alma discussion
As I know it is something like flash and there is nothing required from server side. You should just place silverlight files to site directory and it will be parsed and showed on client's side by his browser.
It should be installed on client's computers for parsing silverlight files from Plesk server. Nothing should be installed on Plesk, just silverlight files should be placed to appropriate folders.