VSCode typescript intellisense doesn't suggest interface in nested namespaces

I have a two-level nested namespaces with bunch of interfaces in global scope.

declare global {
  namespace A {
    namespace B {
      interface I1 {
      }
      interface I2 {
      }
    }
  }
}

I write, for example, some class C with A.B.I1 interface implementation.

class C implements A.B.I1 {}

Ts compiler implements it properly, but when typing A.B ... there is no suggestions of interfaces, declared in namespace B.

Checked in other IDEs: suggestions appear in WebStorm and not in Visual Studio 2019.

VSCode 1.43

Ts 3.8.0

Didn't find anything with such issue.

Would be very grateful, if somebody give an advice..

Thanks.