Update June 3, 2012. Update to the latest CSS 3 schema even if you don't have Web Standards Update. Web Standards Update provides the much wanted HTML5 & CSS3 support to Visual Studio 2010 SP1. It brings VS 2010 intellisense & validation as close to W3C specification as we could get via means of an extension. The most notable supported features by this extension are: HTML5 – Video, Audio, Input T