I am using VS 2015 Enterprise and I have a project that has git as a control source.
When you browse files in VS, there is an option when you right-click on the open file content that you see “Compared to unmodified”. This option is disabled.
I do not change anything configurable in the git repository or in VS, but it is disabled / activated several times. I don't know if there is a way to keep this on all the time.
I can see through many other parameters, such as File History, Annotations, etc. In most cases, only diff is disabled.

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