dotnet/AspNetCore.Docs#9646 dodyg/practical-aspnetcore#152
https://github.com/aspnet/Identity/tree/master/src/UI/Areas/Identity dotnet/AspNetCore.Docs#6838 (comment) https://stackoverflow.com/questions/51610513/can-razor-class-library-pack-static-files-js-css-etc-too https://docs.microsoft.com/en-us/aspnet/core/razor-pages/ui-class?view=aspnetcore-2.1&tabs=visual-studio https://github.com/aspnet/Docs/blob/master/aspnetcore/mvc/advanced/app-parts.md