.NET Core 2.0 and higher are supported from SpecFlow 3.0. .NET Core 3 is supported in SpecFlow 3.1.
SpecFlow supports the Microsoft .NET Platform with a .NET 4.5 runtime assembly (
TechTalk.SpecFlow.dll). This assembly is also suitable for .NET 4.5.2 and .NET 4.6 applications.
If you need to test applications using .NET 3.5 or .NET 4.0, we recommend using SpecFlow v1.9.