Feature Request: blacklist namespaces from extended suggestions

[spbuda]

It would be nice to have some filter controls to prevent certain items from showing up in the IntelliSense.

Use Case: I am working with Unity, and for some reason it still has Boo.Lang which is a deprecated package for their old built in language. Unfortunately, this has a class named List that gets imported whenever I'm trying to add a List if I'm not careful about which type is added. It would be nice to remove this from my sight so I never have to see it again.

[Dreamescaper]

Suggestion is valid, but I'm not sure if it makes sense to invest time on extension side, considering that VS2019 has native import completions now (only types as for now, extension methods TBD).

Probably makes sense to log issue to https://github.com/dotnet/roslyn .