Strange behavior of DialogService (Blazor Components)

On an index component, I use DialogService to open a dialog component:

index component: Index.razor
dialog component: EditEmissionsTypesTranslation.razor

When both the index and the dialog component are opened in Visual Studio 2019, no error occurs. The project can be compiled. (screen 1).

As soon I close the dialog component in Visual Studio, its component class namespace is not available any longer and I get an error on the index component (screen 2).

I captured 2 screenshots and a short video of this behavior for your analyses, but its not allowed to load it up here. Should I mail it to you?