Not really a question, and really a problem with VS2015 itself, but I figured I’d post it here anyway in case people don’t realize this could happen.
I have 4.12 and 4.13 installed. It seems that when you right click on a function or whatnot and click “Go to Definition/Go To Declaration”, it seems to pick randomly from one of either installed engine versions. Maybe not randomly, but it does mess up somehow. For example, I’m currently working in 4.12, and I clicked Go To Definition on a call to InternalSetTimer, but it actually opened the 4.13 version of TimerManager.cpp, which I could tell from hovering my mouse over the filename at the top of Visual Studio.