InvalidOperationException: Attempted to use WebView2 functionality which requires its CoreWebView2 prior to the CoreWebView2 being initialized.  Call EnsureCoreWebView2Async or set the Source property first.
StackTrace:
   在 Microsoft.Web.WebView2.Wpf.WebView2Base.VerifyCoreWebView2()
   在 Microsoft.Web.WebView2.Wpf.WebView2Base.NavigateToString(String htmlContent)
   在 DynamicClass.UpdatePreview()
   在 Microsoft.Web.WebView2.Wpf.WebView2Base.<>c__DisplayClass32_0.<<EnsureCoreWebView2Async>g__Init|0>d.MoveNext()
--- 引发异常的上一位置中堆栈跟踪的末尾 ---
   在 System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   在 System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   在 DynamicClass.<MarkdownEditor_TextChanged>d__2.MoveNext()
--- 引发异常的上一位置中堆栈跟踪的末尾 ---
   在 System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   在 System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   在 System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)