I have various html tags (related to jquery mobile) that Visual Studio is flagging as not valid attributes: For exmaple:
You should install the Web Standards Update and then switch to HTML5 as your default schema:
In addition, you should not use the XHTML 1.0 transitional opening incantation when using HTML 5 attributes. Instead, use the usual HTML5 one:
<!DOCTYPE html>
<html>
In VS2012 will be enough do uncheck 'Use doctype for validation schema detection'.