Visual Studio Debugger未显示鼠标悬停时的变量详细信息，因为它“脱离了上下文”

I have an F# program in Visual Studio 2013 that creates an object at the very beginning. I want to debug the code and look at the value of this object at many different points in time. I was previously able to do this by mousing over the variable in debug mode, but for some reason, I'm no longer able to do that. When I add a watch, it gives me the error: I have an F# program in Visual Studio 2013 that