There are 287 failing tests in WasmTestOnBrowser-System.Net.Http.Functional.Tests when multi-threading is enabled:

• 82 tests fail with the following exception stack trace:

  System.Net.WebSockets.WebSocketException : An internal WebSocket error occurred. Please see the innerException, if present, for more details. 
  ---- System.Runtime.InteropServices.JavaScript.JSException : TypeError: Failed to execute 'send' on 'WebSocket': The provided ArrayBufferView value must not be shared.
     at System.Net.WebSockets.BrowserWebSocket.SendAsyncCore(ArraySegment`1 buffer, WebSocketMessageType messageType, Boolean endOfMessage, CancellationToken cancellationToken)
     at System.Net.Test.Common.LoopbackServer.ListenAsync()
     at System.Net.Test.Common.LoopbackServer.CreateServerAsync(Func`2 funcAsync, Options options)
     at System.Net.Http.Functional.Tests.HttpRequestMessageTest.HttpRequest_BodylessMethod_NoContentLength(String method)
  --- End of stack trace from previous location ---
  ----- Inner Stack Trace -----
     at System.Net.WebSockets.BrowserInterop.WebSocketSend(JSObject webSocket, IntPtr bufferPtr, Int32 bufferLength, Int32 messageType, Boolean endOfMessage)
     at System.Net.WebSockets.BrowserInterop.UnsafeSendSync(JSObject jsWs, ArraySegment`1 buffer, WebSocketMessageType messageType, Boolean endOfMessage)
     at System.Net.WebSockets.BrowserWebSocket.SendAsyncCore(ArraySegment`1 buffer, WebSocketMessageType messageType, Boolean endOfMessage, CancellationToken cancellationToken)
      at Tc (http://127.0.0.1:33027/dotnet.js:5:95034)
      at Object.Oc [as ws_wasm_send] (http://127.0.0.1:33027/dotnet.js:5:93684)
      at _bound_js_INTERNAL_ws_wasm_send (https://dotnet.generated.invalid/_bound_js_INTERNAL_ws_wasm_send:11:21)
      at Object.li (http://127.0.0.1:33027/dotnet.js:5:58079)
      at _mono_wasm_invoke_bound_function (http://127.0.0.1:33027/dotnet.js:14:121580)
      at do_icall (http://127.0.0.1:33027/dotnet.wasm:wasm-function[374]:0x27df1)
      at do_icall_wrapper (http://127.0.0.1:33027/dotnet.wasm:wasm-function[342]:0x2728f)
      at interp_exec_method (http://127.0.0.1:33027/dotnet.wasm:wasm-function[282]:0x1893e)
      at interp_entry (http://127.0.0.1:33027/dotnet.wasm:wasm-function[328]:0x26c8b)
      at interp_entry_static_0 (http://127.0.0.1:33027/dotnet.wasm:wasm-function[401]:0x2895e)
  

• 205 tests fail with the following stack trace:

  System.Runtime.InteropServices.JavaScript.JSException : Error: Assert failed: Unknow converter for type 13 at 2 
      at ho (http://127.0.0.1:33027/dotnet.js:5:35222)
      at Object.ui (http://127.0.0.1:33027/dotnet.js:5:57096)
      at _mono_wasm_bind_js_function (http://127.0.0.1:33027/dotnet.js:14:120525)
      at do_icall (http://127.0.0.1:33027/dotnet.wasm:wasm-function[374]:0x27ee5)
      at do_icall_wrapper (http://127.0.0.1:33027/dotnet.wasm:wasm-function[342]:0x2728f)
      at interp_exec_method (http://127.0.0.1:33027/dotnet.wasm:wasm-function[282]:0x1893e)
      at interp_runtime_invoke (http://127.0.0.1:33027/dotnet.wasm:wasm-function[281]:0x177ee)
      at mono_jit_runtime_invoke (http://127.0.0.1:33027/dotnet.wasm:wasm-function[8284]:0x1affd0)
      at do_runtime_invoke (http://127.0.0.1:33027/dotnet.wasm:wasm-function[2136]:0x91c4d)
      at mono_runtime_invoke_checked (http://127.0.0.1:33027/dotnet.wasm:wasm-function[2134]:0x91bc3)
     at System.Runtime.InteropServices.JavaScript.JSFunctionBinding.BindJSFunctionImpl(String functionName, String moduleName, ReadOnlySpan`1 signatures)
     at System.Runtime.InteropServices.JavaScript.JSFunctionBinding.BindJSFunction(String functionName, String moduleName, ReadOnlySpan`1 signatures)
     at System.Net.Http.BrowserHttpInterop.AbortResponse(JSObject fetchResponse)
     at System.Net.Http.WasmFetchResponse.Dispose()
     at System.Net.Http.BrowserHttpContent.Dispose(Boolean disposing)
     at System.Net.Http.HttpContent.Dispose()
     at System.Net.Http.HttpResponseMessage.Dispose(Boolean disposing)
     at System.Net.Http.HttpResponseMessage.Dispose()
     at System.Net.Http.HttpClient.HandleFailure(Exception e, Boolean telemetryStarted, HttpResponseMessage response, CancellationTokenSource cts, CancellationToken cancellationToken, CancellationTokenSource pendingRequestsCts)
     at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage request, HttpCompletionOption completionOption, CancellationTokenSource cts, Boolean disposeCts, CancellationTokenSource pendingRequestsCts, CancellationToken originalCancellationToken)
     at System.Net.Http.Functional.Tests.HttpClientHandlerTest_Headers.SendAsync_GetWithValidHostHeader_Success(Boolean withPort)
  

  • this is the same exception which causes [wasm-mt] System.Runtime.InteropServices.JavaScript.Http.Tests.HttpRequestMessageTest.BlobUri_Marshal_CorrectValues_Browser test fails #74409

Full console log: https://helixre107v0xdeko0k025g8.blob.core.windows.net/dotnet-runtime-refs-pull-74342-merge-b05c5a1bd5ab47119e/WasmTestOnBrowser-System.Net.Http.Functional.Tests/1/console.902416a0.log?helixlogtype=result