asp.net core with EF and MySQL : extension method not found (no replies)

Hello,

I want to use mysql with EF on asp.net core but when i do :

services.AddDbContext<ContentContext>(opt => opt.UseMySQL());

VisualStudio tells me DbContextOptionBuilder doesn't have an extension method UseMySQL

I have installed the connector using NuGet command:

Install-Package MySql.Data.EntityFrameworkCore -Pre

What am'I missing ?