Visual studio solution explorer not showing form cs file

Question

Cant find user code file of Windows form in solution explorer, now I must right click on form class and choose <>View Code. But there always been cs file at the

Answer 1

Same error here.

Visual Studio Professional 2015. Version installed: 14.0.25431.01 Update 3 (with the KB3165756)

This wrong behaviour started after installing Azure SDK 2.9.6, that installs .NET Core stuff & .NET Core templates into Visual Studio 2015 (actually installed .NET Core Tools (Preview 2) 14.1.21111.0)

If you add Class Library (.NET Core) or Console Application (.NET Core) to your C# solution, the forms.cs become visible again in solution explorer

Before adding Class Library (.NET Core):

After Class Library (.NET Core) added to Solution:

There is something wrong with .NET Core stuff. Hopefully it fixes on future patches.