[🐛 Bug]: [dotnet] WebSocketException from Firefox BiDi on .NET 4.8 after 100 seconds idle

[kevinoid]

Description

On Windows with .NET Framework 4.8 (and presumably 4.7 or 4.6), if the WebDriver BiDi connection to Firefox is idle for more than ~100 seconds, System.Net.WebSockets.WebSocketException (0x80004005): The WebSocket is in an invalid state ('Aborted') for this operation. Valid states are: 'Open, CloseSent' is thrown (caused by a preceding System.Net.WebSockets.WebSocketException (0x80004005): The remote party closed the WebSocket connection without completing the close handshake. exception) when the connection is closed or a BiDi operation is attempted:

Unhandled exception WebSocketException with stack trace

Unhandled Exception: System.Net.WebSockets.WebSocketException: The WebSocket is in an invalid state ('Aborted') for this operation. Valid states are: 'Open, CloseReceived'
   at System.Net.WebSockets.WebSocket.ThrowOnInvalidState(WebSocketState state, WebSocketState[] validStates)
   at System.Net.WebSockets.WebSocketBase.<SendAsyncCore>d__47.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 OpenQA.Selenium.BiDi.Communication.Transport.WebSocketTransport.<SendAsync>d__9.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 OpenQA.Selenium.BiDi.Communication.Broker.<ExecuteCommandCoreAsync>d__19`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 OpenQA.Selenium.BiDi.Communication.Broker.<ExecuteCommandAsync>d__17`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 OpenQA.Selenium.BiDi.Session.SessionModule.<UnsubscribeAsync>d__3.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 OpenQA.Selenium.BiDi.Communication.Broker.<UnsubscribeAsync>d__22.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 OpenQA.Selenium.BiDi.Subscription.<UnsubscribeAsync>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 OpenQA.Selenium.BiDi.Subscription.<DisposeAsync>d__5.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 System.Runtime.CompilerServices.ValueTaskAwaiter.GetResult()
   at Program.<<Main>$>d__0.MoveNext() in C:\Users\Kevin\Source\Repos\SeleniumPostTest\Program.cs:line 19
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Program.<<Main>$>d__0.MoveNext() in C:\Users\Kevin\Source\Repos\SeleniumPostTest\Program.cs:line 19
--- 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 System.Runtime.CompilerServices.TaskAwaiter.GetResult()
   at Program.<Main>(String[] args)

I've been unable to reproduce the issue on .NET 8 or with ChromeDriver or EdgeDriver.

Reproducible Code

using OpenQA.Selenium.BiDi;
using OpenQA.Selenium.Firefox;
using OpenQA.Selenium.Internal.Logging;

using System;
using System.Threading;

Log.SetLevel(LogEventLevel.Trace);

using var webDriver = new FirefoxDriver(new FirefoxOptions()
{
    UseWebSocketUrl = true,
});

await using var bidi = await webDriver.AsBiDiAsync().ConfigureAwait(false);
await using var logSubscription = await bidi.Log
    .OnEntryAddedAsync(Console.WriteLine);

Thread.Sleep(TimeSpan.FromSeconds(100));

Debugging Logs

17:05:05.261 TRACE SeleniumManager: DEBUG geckodriver not found in PATH
17:05:05.267 TRACE SeleniumManager: DEBUG firefox detected at C:\Program Files\Mozilla Firefox\firefox.exe
17:05:05.267 TRACE SeleniumManager: DEBUG Detected browser: firefox 141.0
17:05:05.267 TRACE SeleniumManager: DEBUG Required driver: geckodriver 0.36.0
17:05:05.268 TRACE SeleniumManager: DEBUG geckodriver 0.36.0 already in the cache
17:05:05.268 TRACE SeleniumManager: INFO Driver path: C:\Users\Kevin\.cache\selenium\geckodriver\win64\0.36.0\geckodriver.exe
17:05:05.268 TRACE SeleniumManager: INFO Browser path: C:\Program Files\Mozilla Firefox\firefox.exe
17:05:05.268 TRACE SeleniumManager: Driver path: C:\Users\Kevin\.cache\selenium\geckodriver\win64\0.36.0\geckodriver.exe
17:05:05.268 TRACE SeleniumManager: Browser path: C:\Program Files\Mozilla Firefox\firefox.exe
1753398305620   geckodriver     INFO    Listening on 127.0.0.1:52126
17:05:08.911 DEBUG HttpCommandExecutor: Executing command: []: newSession
17:05:09.086 TRACE HttpCommandExecutor: >> POST RequestUri: http://localhost:52126/session, Content: System.Net.Http.ByteArrayContent, Headers: 2
{"capabilities":{"firstMatch":[{"browserName":"firefox","webSocketUrl":true,"moz:firefoxOptions":{"binary":"C:\\Program Files\\Mozilla Firefox\\firefox.exe","prefs":{"remote.active-protocols":1}}}]}}
1753398309088   mozrunner::runner       INFO    Running command: "C:\\Program Files\\Mozilla Firefox\\firefox.exe" "--marionette" "--remote-debugging-port" "52127" "--remote-allow-hosts" "localhost" "-no-remote" "-profile" "C:\\Users\\Kevin\\AppData\\Local\\Temp\\rust_mozprofileQu2EKS"
Read port: 52133
17:05:12.092 TRACE HttpCommandExecutor: << StatusCode: 200, ReasonPhrase: OK, Content: System.Net.Http.StreamContent, Headers: 2
17:05:12.380 DEBUG HttpCommandExecutor: Response: (6f94cb3b-f685-416c-bcff-d2ff8c1a5e48 Success: System.Collections.Generic.Dictionary`2[System.String,System.Object])
17:05:13.392 TRACE WebSocketTransport: BiDi SND --> {"id":1,"method":"session.subscribe","params":{"events":["log.entryAdded"]}}
17:05:13.427 TRACE WebSocketTransport: BiDi RCV <-- {"type":"success","id":1,"result":{"subscription":"6cc48687-88fd-42b0-a86d-fa1b308887d2"}}
17:06:53.255 ERROR Broker: Couldn't process received BiDi remote message: System.Net.WebSockets.WebSocketException (0x80004005): The remote party closed the WebSocket connection without completing the close handshake.
   at System.Net.WebSockets.WebSocketBase.WebSocketOperation.<Process>d__19.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 System.Net.WebSockets.WebSocketBase.<ReceiveAsyncCore>d__45.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at OpenQA.Selenium.BiDi.Communication.Transport.WebSocketTransport.<ReceiveAsync>d__8.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at OpenQA.Selenium.BiDi.Communication.Broker.<ReceiveMessagesAsync>d__15.MoveNext()
17:06:53.375 ERROR Broker: Couldn't process received BiDi remote message: System.Net.WebSockets.WebSocketException (0x80004005): The WebSocket is in an invalid state ('Aborted') for this operation. Valid states are: 'Open, CloseSent'
   at System.Net.WebSockets.WebSocket.ThrowOnInvalidState(WebSocketState state, WebSocketState[] validStates)
   at System.Net.WebSockets.WebSocketBase.<ReceiveAsyncCore>d__45.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at OpenQA.Selenium.BiDi.Communication.Transport.WebSocketTransport.<ReceiveAsync>d__8.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at OpenQA.Selenium.BiDi.Communication.Broker.<ReceiveMessagesAsync>d__15.MoveNext()
17:06:53.491 TRACE WebSocketTransport: BiDi SND --> {"id":2,"method":"session.unsubscribe","params":{"subscriptions":["6cc48687-88fd-42b0-a86d-fa1b308887d2"]}}
17:06:53.519 ERROR Broker: Couldn't process received BiDi remote message: System.Net.WebSockets.WebSocketException (0x80004005): The WebSocket is in an invalid state ('Aborted') for this operation. Valid states are: 'Open, CloseSent'
   at System.Net.WebSockets.WebSocket.ThrowOnInvalidState(WebSocketState state, WebSocketState[] validStates)
   at System.Net.WebSockets.WebSocketBase.<ReceiveAsyncCore>d__45.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at OpenQA.Selenium.BiDi.Communication.Transport.WebSocketTransport.<ReceiveAsync>d__8.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at OpenQA.Selenium.BiDi.Communication.Broker.<ReceiveMessagesAsync>d__15.MoveNext()
17:06:53.772 ERROR Broker: Couldn't process received BiDi remote message: System.Net.WebSockets.WebSocketException (0x80004005): The WebSocket is in an invalid state ('Aborted') for this operation. Valid states are: 'Open, CloseSent'
   at System.Net.WebSockets.WebSocket.ThrowOnInvalidState(WebSocketState state, WebSocketState[] validStates)
   at System.Net.WebSockets.WebSocketBase.<ReceiveAsyncCore>d__45.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at OpenQA.Selenium.BiDi.Communication.Transport.WebSocketTransport.<ReceiveAsync>d__8.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at OpenQA.Selenium.BiDi.Communication.Broker.<ReceiveMessagesAsync>d__15.MoveNext()
17:06:54.155 DEBUG HttpCommandExecutor: Executing command: [6f94cb3b-f685-416c-bcff-d2ff8c1a5e48]: quit
17:06:54.156 TRACE HttpCommandExecutor: >> DELETE RequestUri: http://localhost:52126/session/6f94cb3b-f685-416c-bcff-d2ff8c1a5e48, Content: null, Headers: 2
17:06:57.750 TRACE HttpCommandExecutor: << StatusCode: 200, ReasonPhrase: OK, Content: System.Net.Http.StreamContent, Headers: 2
17:06:57.751 DEBUG HttpCommandExecutor: Response: ( Success: )

[selenium-ci]

@kevinoid, thank you for creating this issue. We will troubleshoot it as soon as we can.

Selenium Triage Team: remember to follow the Triage Guide

[nvborisenko]

@kevinoid thanks for interesting case, I reproduced this issue. This issue is only about .NET Framework 4.x and Firefox. Network module implementation in .NET Framework is not very good.

Workarounds:

• Don't use .NET Framework, migrate to .NET 8;
• Increase System.Net.ServicePointManager.MaxServicePointIdleTime (default is 100 seconds). Not sure what is reasonable value should be in your case, 2 hours? Who knows... But please be aware it is global setting influences on all network communication in your application.
• Run ping/pong game in background to keep the connection alive (probably it is good option: Task.Run(bidi.StatusAsync()));

Questions:

• Given that it is OK with Chrome/Edge, then something with Firefox only?.. Most likely Firefox doesn't play ping/pong game? I am not experienced in so low-level coding.
• Should Selenium just try/catch? I think we can try/catch this particular exception and reason, but what is next? Initiate new socket connection?..

@whimboo probably you know some hidden stones in FF and WebSockets topic?

[kevinoid]

Thanks @nvborisenko! That all sounds right to me. Calling bidi.StatusAsync() every 60 seconds is a great workaround, thanks for the suggestion!

I'd like to better understand why it only occurs for Firefox on .NET Framework before suggesting a fix. I'll try to set some time aside to investigate next week.

[hheexx]

I may have similiar problem with Firefox on .net 9.

Couldn't process received BiDi remote message: System.Net.WebSockets.WebSocketException (0x80004005): The WebSocket is in an invalid state ('CloseReceived') for this operation. Valid states are: 'Open, CloseSent'
at System.Net.WebSockets.ManagedWebSocket.ThrowIfInvalidState(WebSocketState[] validStates)
at System.Net.WebSockets.ManagedWebSocket.ReceiveAsync(ArraySegment`1 buffer, CancellationToken cancellationToken)

I'm not sure is it tied to inactivity...

[nvborisenko]

@hheexx yes, this is issue we can resolve. CloseReceived remote-end wants to close connection. Can you please help to understand why... because of inactivity? Or browser has been closed?..

Let's gather using scenarios before apply proper fix. We already see different behaviors of combinations .NetFramework/.Net/Firefox. At first glance we would introduce reconnect logic, but it is not clear when to reconnect. The most interesting question why Firefox wants to close a connection if the connection is kind of persistent, we are always listening to incoming messages. I see only one scenario when browser closes, then it wants to close a connection, and selenium should react properly.

[nvborisenko]

Reproduced locally:

using var driver = new FirefoxDriver(new FirefoxOptions { UseWebSocketUrl = true });

await using var bidi = await driver.AsBiDiAsync();

driver.Dispose(); // close the browser

await Task.Delay(1000); // still listening to incoming BiDi messages

@hheexx most likely you dispose the driver before disposing BiDi connection. If this is a case, then it will be implicitly resolved by #16095, meaning you will not be aware of BiDi disposal.

For the history:

Firefox:

The WebSocket is in an invalid state ('CloseReceived') for this operation. Valid states are: 'Open, CloseSent'

Chrome:

The WebSocket is in an invalid state ('Aborted') for this operation. Valid states are: 'Open, CloseSent'

[hheexx]

@nvborisenko I think that seams to be the case. From time to time I am doing driver.Quit() to recycle the browser. I assumed disposing all connections would be automatic.

[nvborisenko]

Perfect! Now we understand the case. Just dispose BiDi object before disposing Driver. Temporary you are the owner of BiDi object, please dispose. Yeah, it is not ideal :( Soon, it will be resolved. But thanks for the case.

PS: We want to do it automatic here: #16095

[hheexx]

@nvborisenko one more thing....

My host application for webdirver is of console type. Usual way for exiting console applications is ctrl+c. Unfortunately when you press ctrl+c windows also sends this command to child processes including firefox which exits by itself. Thats puts my application in a similar situation that connection to firefox is lost and webdriver lib starts printing errors above in a loop blocking me from exiting the app.

My point is that in any case that connection dies from the other side you should probably throw some exception and terminate the connection instead of printing error in a tight loop indefinitely.....