Project fails to load if folders nested inside Content folder

[ChargerIIC]

I started a new F# MVC project and decided I wanted my bootstrap css files inside a subfolder called 'css'. I found out that if there is a subfolder inside the content folder the project will work up until any operation tries to reload the project. When this happens the following error occurs:

c:\users\User\documents\visual studio 2013\Projects\FSharpWeb1\FSharpWeb1\FSharpWeb1.fsproj : error : The project 'FSharpWeb1.fsproj' could not be opened because opening it would cause a folder to be rendered multiple times in the solution explorer. One such problematic item is 'Content\css\Site.css'. To open this project in Visual Studio, first edit the project file and fix the problem.

I popped open the project file and the Site.css file was only referenced once in the entire file. I've been able to repeat this issue by doing the same thing in other projects, but not in the tradition C# MVC template

[ChargerIIC]

Also happens if you simply add a folder that's not part of the default set. I know F# doesn't have a natural understanding of folders, but for content this is really annoying.