Every time I typed a character in Visual Studio 2015 in my WPF project. Just Code would lock up Visual Studio. I just disabled Just Code and it is now working fine. Not sure what caused Just Code to suddenly decide it would lock up everything, when it was working perfectly prior.
But just an FYI if you have a Visual Studio Locking up when you enter a character try disabling Just Code first, as it seems like it is likely the reason for it locking up.