@NikolaiDante, yes, you can install Visual Studio "15" Preview with Visual Studio 2015. I installed the preview of Visual Studio 2015 and Visual Studio "15", and both work fine.

Even if you see in the screenshot “I am using 4 versions of Visual Studio (Visual Studio 2012, Visual Studio 2013, Visual Studio 2015 and Visual Studio“ 15 ”), and all 4 versions work fine.
Banketeshvar narayan
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