Generating the Tables via dotnet ef database update is working as expected if the Firebird-Server Version >= 3.0!
But running the same with Firebird-Server Version 2.5 leads to the following error:

D:\Source\CodeFirstTest\CodeFirstTest>dotnet ef database update -c CodeFirstTest.Model.FirebirdBloggingContext

Applying migration '20191001083549_Initial'.
Failed executing DbCommand (23ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
CREATE TABLE "Blogs" (
    "BlogId" INTEGER GENERATED BY DEFAULT AS IDENTITY NOT NULL,
    "Name" BLOB SUB_TYPE TEXT,
    CONSTRAINT "PK_Blogs" PRIMARY KEY ("BlogId")
);
FirebirdSql.Data.FirebirdClient.FbException (0x80004005): Dynamic SQL Error
SQL error code = -104
Token unknown - line 2, column 32
BY ---> Dynamic SQL Error
SQL error code = -104
Token unknown - line 2, column 32
BY
   at FirebirdSql.Data.FirebirdClient.FbCommand.ExecuteNonQuery()
   at Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommand.Execute(IRelationalConnection connection, DbCommandMethod executeMethod, IReadOnlyDictionary`2 parameterValues)
   at Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommand.ExecuteNonQuery(IRelationalConnection connection, IReadOnlyDictionary`2 parameterValues)
   at Microsoft.EntityFrameworkCore.Migrations.Internal.MigrationCommandExecutor.ExecuteNonQuery(IEnumerable`1 migrationCommands, IRelationalConnection connection)
   at Microsoft.EntityFrameworkCore.Migrations.Internal.Migrator.Migrate(String targetMigration)
   at Microsoft.EntityFrameworkCore.Design.Internal.MigrationsOperations.UpdateDatabase(String targetMigration, String contextType)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.Execute(Action action)
Dynamic SQL Error
SQL error code = -104
Token unknown - line 2, column 32
BY