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dotnet ef migrations add throws exception

See original GitHub issue

I have a ASP.NET Core 3 project with database context using EF Core 3 and SQL Server. When I add a new migration, it fails with NullReferenceException error.

Steps to reproduce

dotnet ef migrations add UpdateDatabase1 -c ApplicationDbContext

Verbose log: https://gist.github.com/jozefizso/b932c31b5b78f3558468ea605aadb505

Exception reported to console:

System.NullReferenceException: Object reference not set to an instance of an object.
   at Microsoft.EntityFrameworkCore.Metadata.Internal.EntityType.OnAnnotationSet(String name, IConventionAnnotation annotation, IConventionAnnotation oldAnnotation)
   at Microsoft.EntityFrameworkCore.Metadata.Internal.ConventionAnnotatable.OnAnnotationSet(String name, Annotation annotation, Annotation oldAnnotation)
   at Microsoft.EntityFrameworkCore.Infrastructure.Annotatable.RemoveAnnotation(String name)
   at Microsoft.EntityFrameworkCore.Infrastructure.Annotatable.Microsoft.EntityFrameworkCore.Metadata.IMutableAnnotatable.RemoveAnnotation(String name)
   at Microsoft.EntityFrameworkCore.Migrations.Internal.SnapshotModelProcessor.ProcessElement(IAnnotatable metadata, String version)
   at Microsoft.EntityFrameworkCore.Migrations.Internal.SnapshotModelProcessor.ProcessElement(IEntityType entityType, String version)
   at Microsoft.EntityFrameworkCore.Migrations.Internal.SnapshotModelProcessor.Process(IModel model)
   at Microsoft.EntityFrameworkCore.Migrations.Design.MigrationsScaffolder.ScaffoldMigration(String migrationName, String rootNamespace, String subNamespace, String language)
   at Microsoft.EntityFrameworkCore.Design.Internal.MigrationsOperations.AddMigration(String name, String outputDir, String contextType)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.AddMigrationImpl(String name, String outputDir, String contextType)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.AddMigration.<>c__DisplayClass0_0.<.ctor>b__0()
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.<>c__DisplayClass3_0`1.<Execute>b__0()
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.Execute(Action action)
Object reference not set to an instance of an object.

Further technical details

EF Core version: 3.0.0 Database provider: Microsoft.EntityFrameworkCore.SqlServer Target framework: .NET Core 3.0 Operating system: Windows 10 IDE: Visual Studio 2019 16.3