I keep getting HTML5 syntax errors with MVC3

Question

Are these kind of errors valid and how can I resolve. Doesn't HTML5 allow this code?

<button title="" disabled="disabled" >&gt;&gt;</button>

Validation: (HTML5) - the values permitted for this attribute do not include 'disabled'

Answer 1

Check Web Standards Update for Microsoft Visual Studio 2010 SP1 that improves html5/css3 validation and intellisense support.

Answer 2

I also had to change my Text-Editor preferences to get VS to recognize the HTML5 controls (for others that arrive here via Google like me).

In VS, go to Tools > Options and select TextEditor/HTML/Validation on the left pane, then select HTML5.