Community edition, VS2019, Web Page Application - no designer

I created a new web Page App but there is no designer. Page1.designer.cs file is there but no menu to show the designer

[Edit] After I closed the solution and re-opened, the “View designer” menu appeared. However, clicking it leads to an error:

“Unable to cast object of type ‘Wisej.Web.Page’ to type ‘Wisej.Core.IWisejControl’

and designer is not showing.

Note that I got the same error after creating, closing and re-opening every other type of Wisej project