I was just playing around in ASP.NET Core to see what it was like. Spent way too much time just getting it up and running plus this issue. I ended up repairing VS2015 to get everything back to normal and then dropped it for now. I will revisit it in the future when I have more time.
BTW, I always keep Telerik up to date and I did confirm we were running the same version. Maybe it is an interaction with another extension. If I find out, I will post an update.
Thanks for the response!