Quick Fix - Display App Center in Sitecore Admin UI
Everybody know how Silverlight is poorly supported by modern browsers. However Sitecore still use it for its App Center.
Well, chop chop, quick fix: https://ftp.mozilla.org/pub/firefox/releases/52.0/win64/en-US/
And....if you are not using FF for anything (like me)...just tell FF not to automatically update itself...
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