O script NPM 'start' saiu sem indicar que a CLI Angular estava atendendo solicitações

Estou tentando iniciar um .NET Core 2 / Angular 6 SPA. Criei um aplicativo Angular 5 usando "dotnet new angular" e depois procedi à atualização usandoeste guia de angular.io. Depois de concluir a atualização, tentei executar o aplicativo usando "dotnet run" e recebo uma página de erro feia com o erro:

Ocorreu uma exceção não tratada durante o processamento da solicitação.

AggregateException: um ou mais erros. (Ocorreu um ou mais erros. (O script NPM 'start' saiu sem indicar que a CLI Angular estava atendendo solicitações. A saída do erro foi: Opção desconhecida: '--extractCss'

InvalidOperationException: o script NPM 'start' saiu sem indicar que a CLI Angular estava atendendo a solicitações. A saída do erro foi: Opção desconhecida: '--extractCss'

Pensando que talvez eu tenha perdido um passo durante a atualização, tentei uma segunda vez e obtive o mesmo erro.

Aqui estão as etapas que eu segui depois de criar o aplicativo:

npm install -g @angular/cli
npm install @angular/cli
ng update @angular/cli
ng update @angular/core
npm install --save @angular/material @angular/cdk @angular/animations hammerjs 
npm install -g rxjs-tslint
rxjs-5-to-6-migrate -p src/tsconfig.app.json

Estou executando o Node versão 9.4.0 e o .Net Core 2.1.200 no Windows 10 (1703) Enterprise.

Alguma ideia de como consertar isso? Aqui está um rastreamento completo da pilha:

 ---> System.IO.EndOfStreamException: Attempted to read past the end of the stream.
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.SpaServices.AngularCli.AngularCliMiddleware.<StartAngularCliServerAsync>d__3.MoveNext()
   --- End of inner exception stack trace ---
   at Microsoft.AspNetCore.SpaServices.AngularCli.AngularCliMiddleware.<StartAngularCliServerAsync>d__3.MoveNext()
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at Microsoft.AspNetCore.SpaServices.AngularCli.AngularCliMiddleware.<>c.<Attach>b__2_0(Task`1 task)
   at System.Threading.Tasks.ContinuationResultTaskFromResultTask`2.InnerInvoke()
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot)
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at Microsoft.AspNetCore.SpaServices.Extensions.Util.TaskTimeoutExtensions.<WithTimeout>d__1`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.SpaServices.Extensions.Proxy.SpaProxy.<PerformProxyRequest>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Builder.SpaProxyingExtensions.<>c__DisplayClass2_0.<<UseProxyToSpaDevelopmentServer>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Builder.RouterMiddleware.<Invoke>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.<Invoke>d__7.MoveNext()
---> (Inner Exception #0) System.AggregateException: One or more errors occurred. (The NPM script 'start' exited without indicating that the Angular CLI was listening for requests. The error output was: Unknown option: '--extractCss'

) ---> System.InvalidOperationException: The NPM script 'start' exited without indicating that the Angular CLI was listening for requests. The error output was: Unknown option: '--extractCss'

 ---> System.IO.EndOfStreamException: Attempted to read past the end of the stream.
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.SpaServices.AngularCli.AngularCliMiddleware.<StartAngularCliServerAsync>d__3.MoveNext()
   --- End of inner exception stack trace ---
   at Microsoft.AspNetCore.SpaServices.AngularCli.AngularCliMiddleware.<StartAngularCliServerAsync>d__3.MoveNext()
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at Microsoft.AspNetCore.SpaServices.AngularCli.AngularCliMiddleware.<>c.<Attach>b__2_0(Task`1 task)
   at System.Threading.Tasks.ContinuationResultTaskFromResultTask`2.InnerInvoke()
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot)
---> (Inner Exception #0) System.InvalidOperationException: The NPM script 'start' exited without indicating that the Angular CLI was listening for requests. The error output was: Unknown option: '--extractCss'

 ---> System.IO.EndOfStreamException: Attempted to read past the end of the stream.
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.SpaServices.AngularCli.AngularCliMiddleware.<StartAngularCliServerAsync>d__3.MoveNext()
   --- End of inner exception stack trace ---
   at Microsoft.AspNetCore.SpaServices.AngularCli.AngularCliMiddleware.<StartAngularCliServerAsync>d__3.MoveNext()<---
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