I have just moved from asp.net core 2.2 to 3.1 and now I am getting following exception
Could not load type 'Microsoft.EntityFrameworkCore.RelationalReferenceCollectionBuilderExtensions' from assembly 'Microsoft.EntityFrameworkCore.Relational, Version=3.1.3.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'
As you can see from https://docs.microsoft.com/en-us/dotnet/api/microsoft.entityframeworkcore.relationalreferencecollectionbuilderextensions?view=efcore-2.2&viewFallbackFrom=efcore-3.1, that class (RelationalReferenceCollectionBuilderExtensions
) no longer exists in 3.1.