I have just installed Web Essentials 2012 for VS2012, but when I open a .less file, nothing is highlighted and the preview window doesn't display. Are there any settings or something I am missing to make this work?
Web Essentials does not include Less tools anymore, you need to install the ASP.NET and Web Tools 2012.2 update to work with Less. A bit more details can be found on Web Essential's developer's blog.
来源：https://stackoverflow.com/questions/15323250/less-files-in-visual-studio-not-syntax-highlighted