GetActiveTextViewAsync intermittently throws exceptions (ArgumentException and RemoteInvocationException)

[garrettpauls]

We have an in-house extension that adds a command which uses GetActiveTextViewAsync. This command works most of the time, however GetActiveTextViewAsync throws exceptions intermittently, typically after VS has been running for a while. We haven't been able to narrow down what specifically causes it to happen yet, however it has failed with two different exceptions so far:

System.ArgumentException: Document version is no longer available. Try again with newer version.
   at Microsoft.VisualStudio.Extensibility.EditorHostService.TextDocumentObserver.GetTextDocumentAsync(Int32 version, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.Extensibility.EditorHostService.EditorHostServiceImpl.CreateTextDocumentAsync(Uri documentUri, Int32 version, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.Extensibility.EditorHostService.EditorHostServiceImpl.CreateTextViewAsync(TextViewContract textView, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.Extensibility.EditorHostService.EditorHostServiceImpl.CreateActiveTextViewAsync(IReadOnlyDictionary`2 clientContext, CancellationToken cancellationToken)
   at ExampleCommand.ExecuteCommandAsync(ClientContext context, CancellationToken cancellationToken)

and

StreamJsonRpc.RemoteInvocationException: Cannot subscribe to document, document is not open
   at StreamJsonRpc.JsonRpc.InvokeCoreAsync[TResult](RequestId id, String targetName, IReadOnlyList`1 arguments, IReadOnlyList`1 positionalArgumentDeclaredTypes, IReadOnlyDictionary`2 namedArgumentDeclaredTypes, CancellationToken cancellationToken, Boolean isParameterObject)
   at Microsoft.VisualStudio.Extensibility.EditorHostService.EditorHostServiceImpl.CreateDocumentObserverAsync(ITextEditorSynchronizationServiceContract syncService, Uri documentUri, Int32 version, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.Extensibility.EditorHostService.EditorHostServiceImpl.GetOrCreateTextDocumentObserverAsync(Uri documentUri, Int32 version, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.Extensibility.EditorHostService.EditorHostServiceImpl.CreateTextDocumentAsync(Uri documentUri, Int32 version, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.Extensibility.EditorHostService.EditorHostServiceImpl.CreateTextViewAsync(TextViewContract textView, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.Extensibility.EditorHostService.EditorHostServiceImpl.CreateActiveTextViewAsync(IReadOnlyDictionary`2 clientContext, CancellationToken cancellationToken)
   at ExampleCommand.ExecuteCommandAsync(IClientContext context, CancellationToken cancellationToken)
RPC server exception:
System.InvalidOperationException: Cannot subscribe to document, document is not open
      at Microsoft.VisualStudio.Editor.Implementation.TextEditorSynchronizationService.<SubscribeToDocumentChangesAsync>d__21.MoveNext()

I'm at a loss of how to troubleshoot these. If there's any additional details I can add to our logging to assist please let me know.

This is a simplified version of the command we're using. I've removed the logic it does for simplicity, as the error happens right when we get the active text view, however I can include more details if requested.

public class ExampleCommand : Command
{
	protected readonly TraceSource Log;

	public override async Task ExecuteCommandAsync(IClientContext context, CancellationToken cancellationToken)
	{
		// this is exactly what the command does before the problem line, I have not removed anything here
		Log.TraceInformation("Example command starting");
		var stopwatch = Stopwatch.StartNew();

		try
		{
			var editor = context.Extensibility.Editor();

			// vvvvv this line throws exceptions periodically vvvvv
			var textView = await editor.GetActiveTextViewAsync(context, cancellationToken);
			// ^^^^^ this line throws exceptions periodically ^^^^^

			if (textView != null)
			{
				// this part works fine
			}
		}
		catch (Exception ex)
		{
			Log.TraceEvent( TraceEventType.Error, 1, "Unhandled exception: {0}", ex );
			await context.Extensibility.Shell()
				.ShowPromptAsync(
					$"Unhandled exception:\n{ex}",
					PromptOptions.OK,
					cancellationToken);
			throw;
		}
		finally
		{
			Log.TraceInformation( "Example command completed in {0}ms", stopwatch.ElapsedMilliseconds );
		}
	}

	public override CommandConfiguration CommandConfiguration { get; }
}

Both of these have occurred in VS 2026 version 18.2.1. The extension targets framework net8.0 and references:

• Microsoft.VisualStudio.Extensibility.Build - 17.14.40608
• Microsoft.VisualStudio.Extensibility.Sdk - 17.14.40608