Add Suave - Open Declarations not working

Question

I add Suave.io to my project - so far empty - via NuGet and that's alright. But none of the open Suave declarations work yielding "The namespace or module "Suave" is not defined." The following works in script file though:

#r ".../Suave.dll"
open Suave

Answer 1

Targeting .NET 4.7 (rather than 4.5.2) solved the issue. Wierd