Visual studio 2019 go to definition and Intellisense not working

Question

I have noticed a weird issue with Visual Studio 2019 v16.0.1 the IntelliSense about \"Using directive is unnecessary\" normally grey is missing and type reference suggestion

Answer 1

Go to Tools -> Options -> Text Editor -> All Languages -> General. Make sure “Auto List Members” is checked. Also, make sure “Parameter Information” is checked.