Using VS 2015 Update 3, just installed ReSharper Ultimate 2016.1.2
It seems ReSharper can't resolve the Razor syntax. I'm getting errors like this in the cshtml file:
Cannot resolve symbol 'RenderBody'
but it does compile and run.
This problem seemed similar to the one here, but the comments in that thread seemed to have gone off topic.
I tried clearing the cache, for what it's worth, as described here, but it didn't work.
I'm also using MVC 6 with ASP.NET Core, if that matters.