[wasm] Misc Debugger improvements (including tests) (#65752)

* [wasm][debugger] Fail test if an assertion is detected

* [wasm][debugger] Make DevToolsProxy's `pending_ops` thread-safe

Currently, `pending_ops` can get written by different threads at the
same time, and also read in parallel. This causes tests to randomly fail
with:

```
DevToolsProxy::Run: Exception System.ArgumentException: The tasks argument included a null value. (Parameter 'tasks')
    at System.Threading.Tasks.Task.WhenAny(Task[] tasks)
    at Microsoft.WebAssembly.Diagnostics.DevToolsProxy.Run(Uri browserUri, WebSocket ideSocket) in /_/src/mono/wasm/debugger/BrowserDebugProxy/DevToolsProxy.cs:line 269
```

Instead, we use `Channel<T>` to add the ops, and then read those in
the main loop, and add to the *local* `pending_ops` list.

* [wasm] Install chrome for debugger tests

- controlled by `$(InstallChromeForDebuggerTests)` which defaults to
`true` for non-CI docker containers
- Useful for using the correct chrome version when testing locally, or
on codespaces

- Also, add support for detecting, and defaulting to such an
installation

* [wasm][debugger] Disable tests failing with runtime assertions

`DebuggerTests.EvaluateOnCallFrameTests.EvaluateSimpleMethodCallsError`: https://github.com/dotnet/runtime/issues/65744
`DebuggerTests.ArrayTests.InvalidArrayId`: https://github.com/dotnet/runtime/issues/65742

* [wasm][debugger] Fix NRE with `"null"` condition for a breakpoint

`ConditionalBreakpoint` test fails.
The test with condition=`"null"` failed with a NRE, instead of correctly
handling it as a condition that returns null.

```
Unable evaluate conditional breakpoint: System.Exception: Internal Error: Unable to run (null ),
    error: Object reference not set to an instance of an object..
    ---> System.NullReferenceException: Object reference not set to an instance of an object.
            at Microsoft.WebAssembly.Diagnostics.EvaluateExpression.CompileAndRunTheExpression(String expression, MemberReferenceResolver resolver, CancellationToken token) in /workspaces/runtime/src/mono/wasm/debugger/BrowserDebugProxy/EvaluateExpression.cs:line 399
            --- End of inner exception stack trace ---
            at Microsoft.WebAssembly.Diagnostics.EvaluateExpression.CompileAndRunTheExpression(String expression, MemberReferenceResolver resolver, CancellationToken token) in /workspaces/runtime/src/mono/wasm/debugger/BrowserDebugProxy/EvaluateExpression.cs:line 407
            at Microsoft.WebAssembly.Diagnostics.MonoProxy.EvaluateCondition(SessionId sessionId, ExecutionContext context, Frame mono_frame, Breakpoint bp, CancellationToken token) in /workspaces/runtime/src/mono/wasm/debugger/BrowserDebugProxy/MonoProxy.cs:line 801 condition:null
```

* [wasm] Improve default message for ReturnAsErrorException,

.. since we seem to be not catching them as intended in many places.

* [wasm] Better log, and surface errors in evaluation conditional

.. breakpoints.
Catch the proper exception `ReturnAsErrorException`, so we can get the
actual error message. And log that as an error for the user too.

* [wasm][debugger] Allow setting proxy port for BrowserDebugHost

.. with `--proxy-port=<port>`.

Fixes https://github.com/dotnet/runtime/issues/65209 .

* [wasm][debugger] Handle errors in getting value for locals

Essentially, catch, and skip.

* message cleanup

* remove trailing space

13 files changed, 207 insertions, 64 deletions

diff --git a/src/libraries/sendtohelix-wasm.targets b/src/libraries/sendtohelix-wasm.targets
index ee6267244d3..0c80ec4ec1f 100644
--- a/src/libraries/sendtohelix-wasm.targets
+++ b/src/libraries/sendtohelix-wasm.targets
@@ -38,8 +38,8 @@
     <HelixPreCommand Include="export XHARNESS_DISABLE_COLORED_OUTPUT=true" />
     <HelixPreCommand Include="export XHARNESS_LOG_WITH_TIMESTAMPS=true" />
 
-    <HelixPreCommand Condition="'$(NeedsToRunOnBrowser)' == 'true'" Include="export PATH=$HELIX_CORRELATION_PAYLOAD/chromedriver_linux64:$PATH" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnBrowser)' == 'true'" Include="export PATH=$HELIX_CORRELATION_PAYLOAD/chrome-linux:$PATH" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnBrowser)' == 'true'" Include="export PATH=$HELIX_CORRELATION_PAYLOAD/$(ChromeDriverDirName):$PATH" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnBrowser)' == 'true'" Include="export PATH=$HELIX_CORRELATION_PAYLOAD/$(ChromiumDirName):$PATH" />
 
     <!-- Fix symbolic links that are broken already on build machine and also in the correlation payload -->
     <HelixPreCommand Condition="'$(NeedsEMSDKNode)' == 'true'" Include="export HELIX_NODEJS_VERSION=%24(ls $HELIX_CORRELATION_PAYLOAD/build/emsdk/node)" />
@@ -60,8 +60,8 @@
     <HelixPreCommand Include="set XHARNESS_DISABLE_COLORED_OUTPUT=true" />
     <HelixPreCommand Include="set XHARNESS_LOG_WITH_TIMESTAMPS=true" />
 
-    <HelixPreCommand Condition="'$(NeedsToRunOnBrowser)' == 'true'" Include="set PATH=%HELIX_CORRELATION_PAYLOAD%\chromedriver_win32%3B%PATH%" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnBrowser)' == 'true'" Include="set PATH=%HELIX_CORRELATION_PAYLOAD%\chrome-win%3B%PATH%" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnBrowser)' == 'true'" Include="set PATH=%HELIX_CORRELATION_PAYLOAD%\$(ChromeDriverDirName)%3B%PATH%" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnBrowser)' == 'true'" Include="set PATH=%HELIX_CORRELATION_PAYLOAD%\$(ChromiumDirName)%3B%PATH%" />
 
     <HelixPreCommand Condition="'$(NeedsEMSDKNode)' == 'true'" Include="for /f %%i in ('dir %HELIX_CORRELATION_PAYLOAD%\build\emsdk\node /b') do set HELIX_NODEJS_VERSION=%%i" />
     <HelixPreCommand Condition="'$(NeedsEMSDKNode)' == 'true'" Include="set PATH=%HELIX_CORRELATION_PAYLOAD%\build\emsdk\node\%HELIX_NODEJS_VERSION%\bin%3B%PATH%" />
@@ -96,6 +96,8 @@
     </When>
   </Choose>
 
+  <Import Project="$(RepoRoot)src\mono\wasm\BrowsersForTesting.props" />
+
   <Target Name="PrepareForBuildHelixWorkItems_Wasm">
     <PropertyGroup>
       <WasmBuildTargetsDir>$([MSBuild]::NormalizeDirectory('$(RepoRoot)', 'src', 'mono', 'wasm', 'build'))</WasmBuildTargetsDir>
@@ -106,26 +108,6 @@
       <WorkItemPrefix Condition="'$(WorkItemPrefix)' == '' and '$(Scenario)' != ''">$(Scenario)-</WorkItemPrefix>
     </PropertyGroup>
 
-    <!-- Version number to revision number mapping from http://omahaproxy.appspot.com/ and find the closest one in
-         https://commondatastorage.googleapis.com/chromium-browser-snapshots/index.html?prefix=Linux_x64/
-         and https://commondatastorage.googleapis.com/chromium-browser-snapshots/index.html?prefix=Win_x64/
-
-         Eg. latest stable version is 96.0.4664.45 with revision 929512.
-         but the closest one available in the snapshosts is 929513.
-         Please make sure to check both platforms as sometime
-         the same snapshot might not be available in one of them.
-    -->
-    <PropertyGroup Condition="'$(BrowserHost)' != 'windows'">
-      <ChromiumRevision>929513</ChromiumRevision>
-      <ChromiumUrl>https://storage.googleapis.com/chromium-browser-snapshots/Linux_x64/$(ChromiumRevision)/chrome-linux.zip</ChromiumUrl>
-      <ChromeDriverUrl>https://storage.googleapis.com/chromium-browser-snapshots/Linux_x64/$(ChromiumRevision)/chromedriver_linux64.zip</ChromeDriverUrl>
-    </PropertyGroup>
-    <PropertyGroup Condition="'$(BrowserHost)' == 'windows'">
-      <ChromiumRevision>929513</ChromiumRevision>
-      <ChromiumUrl>https://storage.googleapis.com/chromium-browser-snapshots/Win_x64/$(ChromiumRevision)/chrome-win.zip</ChromiumUrl>
-      <ChromeDriverUrl>https://storage.googleapis.com/chromium-browser-snapshots/Win_x64/$(ChromiumRevision)/chromedriver_win32.zip</ChromeDriverUrl>
-    </PropertyGroup>
-
     <ItemGroup Condition="'$(NeedsToRunOnBrowser)' == 'true'">
       <HelixCorrelationPayload Include="chromium" Uri="$(ChromiumUrl)" />
       <HelixCorrelationPayload Include="chromedriver" Uri="$(ChromeDriverUrl)" />
diff --git a/src/mono/wasm/BrowsersForTesting.props b/src/mono/wasm/BrowsersForTesting.props
new file mode 100644
index 00000000000..eb0c1476f00
--- /dev/null
+++ b/src/mono/wasm/BrowsersForTesting.props
@@ -0,0 +1,28 @@
+<Project>
+  <!-- Version number to revision number mapping from http://omahaproxy.appspot.com/ and find the closest one in
+    https://commondatastorage.googleapis.com/chromium-browser-snapshots/index.html?prefix=Linux_x64/
+    and https://commondatastorage.googleapis.com/chromium-browser-snapshots/index.html?prefix=Win_x64/
+
+    Eg. latest stable version is 96.0.4664.45 with revision 929512.
+    but the closest one available in the snapshosts is 929513.
+    Please make sure to check both platforms as sometime
+    the same snapshot might not be available in one of them.
+  -->
+  <PropertyGroup Condition="'$(BrowserHost)' != 'windows'">
+    <ChromiumRevision>929513</ChromiumRevision>
+    <ChromiumUrl>https://storage.googleapis.com/chromium-browser-snapshots/Linux_x64/$(ChromiumRevision)/chrome-linux.zip</ChromiumUrl>
+    <ChromeDriverUrl>https://storage.googleapis.com/chromium-browser-snapshots/Linux_x64/$(ChromiumRevision)/chromedriver_linux64.zip</ChromeDriverUrl>
+    <ChromiumDirName>chrome-linux</ChromiumDirName>
+    <ChromeDriverDirName>chromedriver_linux64</ChromeDriverDirName>
+    <ChromiumBinaryName>chrome</ChromiumBinaryName>
+  </PropertyGroup>
+
+  <PropertyGroup Condition="'$(BrowserHost)' == 'windows'">
+    <ChromiumRevision>929513</ChromiumRevision>
+    <ChromiumUrl>https://storage.googleapis.com/chromium-browser-snapshots/Win_x64/$(ChromiumRevision)/chrome-win.zip</ChromiumUrl>
+    <ChromeDriverUrl>https://storage.googleapis.com/chromium-browser-snapshots/Win_x64/$(ChromiumRevision)/chromedriver_win32.zip</ChromeDriverUrl>
+    <ChromiumDirName>chrome-win</ChromiumDirName>
+    <ChromeDriverDirName>chromedriver_win32</ChromeDriverDirName>
+    <ChromiumBinaryName>chrome.exe</ChromiumBinaryName>
+  </PropertyGroup>
+</Project>
diff --git a/src/mono/wasm/README.md b/src/mono/wasm/README.md
index 86e7b569127..2fd07e682ad 100644
--- a/src/mono/wasm/README.md
+++ b/src/mono/wasm/README.md
@@ -143,6 +143,8 @@ To run a test with `FooBar` in the name:
 
 Additional arguments for `dotnet test` can be passed via `MSBUILD_ARGS` or `TEST_ARGS`. For example `MSBUILD_ARGS="/p:WasmDebugLevel=5"`. Though only one of `TEST_ARGS`, or `TEST_FILTER` can be used at a time.
 
+- Chrome can be installed for testing by setting `InstallChromeForDebuggerTests=true` when building the tests.
+
 ## Run samples
 
 The samples in `src/mono/sample/wasm` can be build and run like this:
diff --git a/src/mono/wasm/debugger/BrowserDebugProxy/DevToolsProxy.cs b/src/mono/wasm/debugger/BrowserDebugProxy/DevToolsProxy.cs
index c3f184d056a..567b1d7837e 100644
--- a/src/mono/wasm/debugger/BrowserDebugProxy/DevToolsProxy.cs
+++ b/src/mono/wasm/debugger/BrowserDebugProxy/DevToolsProxy.cs
@@ -8,6 +8,7 @@ using System.Linq;
 using System.Net.WebSockets;
 using System.Text;
 using System.Threading;
+using System.Threading.Channels;
 using System.Threading.Tasks;
 using Microsoft.Extensions.Logging;
 using Newtonsoft.Json;
@@ -24,7 +25,8 @@ namespace Microsoft.WebAssembly.Diagnostics
         private ClientWebSocket browser;
         private WebSocket ide;
         private int next_cmd_id;
-        private List<Task> pending_ops = new List<Task>();
+        private readonly ChannelWriter<Task> _channelWriter;
+        private readonly ChannelReader<Task> _channelReader;
         private List<DevToolsQueue> queues = new List<DevToolsQueue>();
 
         protected readonly ILogger logger;
@@ -33,6 +35,10 @@ namespace Microsoft.WebAssembly.Diagnostics
         {
             string loggerSuffix = string.IsNullOrEmpty(loggerId) ? string.Empty : $"-{loggerId}";
             logger = loggerFactory.CreateLogger($"{nameof(DevToolsProxy)}{loggerSuffix}");
+
+            var channel = Channel.CreateUnbounded<Task>(new UnboundedChannelOptions { SingleReader = true });
+            _channelWriter = channel.Writer;
+            _channelReader = channel.Reader;
         }
 
         protected virtual Task<bool> AcceptEvent(SessionId sessionId, string method, JObject args, CancellationToken token)
@@ -94,7 +100,7 @@ namespace Microsoft.WebAssembly.Diagnostics
             return queues.FirstOrDefault(q => q.CurrentSend == task);
         }
 
-        private void Send(WebSocket to, JObject o, CancellationToken token)
+        private async Task Send(WebSocket to, JObject o, CancellationToken token)
         {
             string sender = browser == to ? "Send-browser" : "Send-ide";
 
@@ -106,7 +112,7 @@ namespace Microsoft.WebAssembly.Diagnostics
 
             Task task = queue.Send(bytes, token);
             if (task != null)
-                pending_ops.Add(task);
+                await _channelWriter.WriteAsync(task, token);
         }
 
         private async Task OnEvent(SessionId sessionId, string method, JObject args, CancellationToken token)
@@ -116,7 +122,7 @@ namespace Microsoft.WebAssembly.Diagnostics
                 if (!await AcceptEvent(sessionId, method, args, token))
                 {
                     //logger.LogDebug ("proxy browser: {0}::{1}",method, args);
-                    SendEventInternal(sessionId, method, args, token);
+                    await SendEventInternal(sessionId, method, args, token);
                 }
             }
             catch (Exception e)
@@ -132,7 +138,7 @@ namespace Microsoft.WebAssembly.Diagnostics
                 if (!await AcceptCommand(id, method, args, token))
                 {
                     Result res = await SendCommandInternal(id, method, args, token);
-                    SendResponseInternal(id, res, token);
+                    await SendResponseInternal(id, res, token);
                 }
             }
             catch (Exception e)
@@ -153,7 +159,7 @@ namespace Microsoft.WebAssembly.Diagnostics
             logger.LogError("Cannot respond to command: {id} with result: {result} - command is not pending", id, result);
         }
 
-        private void ProcessBrowserMessage(string msg, CancellationToken token)
+        private Task ProcessBrowserMessage(string msg, CancellationToken token)
         {
             var res = JObject.Parse(msg);
 
@@ -161,23 +167,30 @@ namespace Microsoft.WebAssembly.Diagnostics
             Log("protocol", $"browser: {msg}");
 
             if (res["id"] == null)
-                pending_ops.Add(OnEvent(res.ToObject<SessionId>(), res["method"].Value<string>(), res["params"] as JObject, token));
+            {
+                return OnEvent(res.ToObject<SessionId>(), res["method"].Value<string>(), res["params"] as JObject, token);
+            }
             else
+            {
                 OnResponse(res.ToObject<MessageId>(), Result.FromJson(res));
+                return null;
+            }
         }
 
-        private void ProcessIdeMessage(string msg, CancellationToken token)
+        private Task ProcessIdeMessage(string msg, CancellationToken token)
         {
             Log("protocol", $"ide: {msg}");
             if (!string.IsNullOrEmpty(msg))
             {
                 var res = JObject.Parse(msg);
                 var id = res.ToObject<MessageId>();
-                pending_ops.Add(OnCommand(
+                return OnCommand(
                     id,
                     res["method"].Value<string>(),
-                    res["params"] as JObject, token));
+                    res["params"] as JObject, token);
             }
+
+            return null;
         }
 
         internal async Task<Result> SendCommand(SessionId id, string method, JObject args, CancellationToken token)
@@ -186,7 +199,7 @@ namespace Microsoft.WebAssembly.Diagnostics
             return await SendCommandInternal(id, method, args, token);
         }
 
-        private Task<Result> SendCommandInternal(SessionId sessionId, string method, JObject args, CancellationToken token)
+        private async Task<Result> SendCommandInternal(SessionId sessionId, string method, JObject args, CancellationToken token)
         {
             int id = Interlocked.Increment(ref next_cmd_id);
 
@@ -204,17 +217,17 @@ namespace Microsoft.WebAssembly.Diagnostics
             //Log ("verbose", $"add cmd id {sessionId}-{id}");
             pending_cmds[msgId] = tcs;
 
-            Send(this.browser, o, token);
-            return tcs.Task;
+            await Send(browser, o, token);
+            return await tcs.Task;
         }
 
-        public void SendEvent(SessionId sessionId, string method, JObject args, CancellationToken token)
+        public Task SendEvent(SessionId sessionId, string method, JObject args, CancellationToken token)
         {
             //Log ("verbose", $"sending event {method}: {args}");
-            SendEventInternal(sessionId, method, args, token);
+            return SendEventInternal(sessionId, method, args, token);
         }
 
-        private void SendEventInternal(SessionId sessionId, string method, JObject args, CancellationToken token)
+        private Task SendEventInternal(SessionId sessionId, string method, JObject args, CancellationToken token)
         {
             var o = JObject.FromObject(new
             {
@@ -224,7 +237,7 @@ namespace Microsoft.WebAssembly.Diagnostics
             if (sessionId.sessionId != null)
                 o["sessionId"] = sessionId.sessionId;
 
-            Send(this.ide, o, token);
+            return Send(ide, o, token);
         }
 
         internal void SendResponse(MessageId id, Result result, CancellationToken token)
@@ -232,13 +245,13 @@ namespace Microsoft.WebAssembly.Diagnostics
             SendResponseInternal(id, result, token);
         }
 
-        private void SendResponseInternal(MessageId id, Result result, CancellationToken token)
+        private Task SendResponseInternal(MessageId id, Result result, CancellationToken token)
         {
             JObject o = result.ToJObject(id);
             if (!result.IsOk)
                 logger.LogError($"sending error response for id: {id} -> {result}");
 
-            Send(this.ide, o, token);
+            return Send(this.ide, o, token);
         }
 
         // , HttpContext context)
@@ -258,10 +271,14 @@ namespace Microsoft.WebAssembly.Diagnostics
                     Log("verbose", $"DevToolsProxy: Client connected on {browserUri}");
                     var x = new CancellationTokenSource();
 
+                    List<Task> pending_ops = new();
+
                     pending_ops.Add(ReadOne(browser, x.Token));
                     pending_ops.Add(ReadOne(ide, x.Token));
                     pending_ops.Add(side_exception.Task);
                     pending_ops.Add(client_initiated_close.Task);
+                    Task<bool> readerTask = _channelReader.WaitToReadAsync(x.Token).AsTask();
+                    pending_ops.Add(readerTask);
 
                     try
                     {
@@ -278,6 +295,16 @@ namespace Microsoft.WebAssembly.Diagnostics
                                 break;
                             }
 
+                            if (readerTask.IsCompleted)
+                            {
+                                while (_channelReader.TryRead(out Task newTask))
+                                {
+                                    pending_ops.Add(newTask);
+                                }
+
+                                pending_ops[4] = _channelReader.WaitToReadAsync(x.Token).AsTask();
+                            }
+
                             //logger.LogTrace ("pump {0} {1}", task, pending_ops.IndexOf (task));
                             if (completedTask == pending_ops[0])
                             {
@@ -285,7 +312,9 @@ namespace Microsoft.WebAssembly.Diagnostics
                                 if (msg != null)
                                 {
                                     pending_ops[0] = ReadOne(browser, x.Token); //queue next read
-                                    ProcessBrowserMessage(msg, x.Token);
+                                    Task newTask = ProcessBrowserMessage(msg, x.Token);
+                                    if (newTask != null)
+                                        pending_ops.Add(newTask);
                                 }
                             }
                             else if (completedTask == pending_ops[1])
@@ -294,7 +323,9 @@ namespace Microsoft.WebAssembly.Diagnostics
                                 if (msg != null)
                                 {
                                     pending_ops[1] = ReadOne(ide, x.Token); //queue next read
-                                    ProcessIdeMessage(msg, x.Token);
+                                    Task newTask = ProcessIdeMessage(msg, x.Token);
+                                    if (newTask != null)
+                                        pending_ops.Add(newTask);
                                 }
                             }
                             else if (completedTask == pending_ops[2])
@@ -314,10 +345,13 @@ namespace Microsoft.WebAssembly.Diagnostics
                                 }
                             }
                         }
+
+                        _channelWriter.Complete();
                     }
                     catch (Exception e)
                     {
                         Log("error", $"DevToolsProxy::Run: Exception {e}");
+                        _channelWriter.Complete(e);
                         //throw;
                     }
                     finally
diff --git a/src/mono/wasm/debugger/BrowserDebugProxy/EvaluateExpression.cs b/src/mono/wasm/debugger/BrowserDebugProxy/EvaluateExpression.cs
index 213a50ae1ce..dc9296b5f6b 100644
--- a/src/mono/wasm/debugger/BrowserDebugProxy/EvaluateExpression.cs
+++ b/src/mono/wasm/debugger/BrowserDebugProxy/EvaluateExpression.cs
@@ -396,7 +396,7 @@ namespace Microsoft.WebAssembly.Diagnostics
                     string.Join("\n", findVarNMethodCall.variableDefinitions) + "\nreturn " + syntaxTree.ToString());
 
                 var state = await newScript.RunAsync(cancellationToken: token);
-                return JObject.FromObject(ConvertCSharpToJSType(state.ReturnValue, state.ReturnValue.GetType()));
+                return JObject.FromObject(ConvertCSharpToJSType(state.ReturnValue, state.ReturnValue?.GetType()));
             }
             catch (CompilationErrorException cee)
             {
@@ -419,7 +419,7 @@ namespace Microsoft.WebAssembly.Diagnostics
         private static object ConvertCSharpToJSType(object v, Type type)
         {
             if (v == null)
-                return new { type = "object", subtype = "null", className = type.ToString(), description = type.ToString() };
+                return new { type = "object", subtype = "null", className = type?.ToString(), description = type?.ToString() };
             if (v is string s)
                 return new { type = "string", value = s, description = s };
             if (NumericTypes.Contains(v.GetType()))
@@ -443,10 +443,11 @@ namespace Microsoft.WebAssembly.Diagnostics
             }
             set { }
         }
-        public ReturnAsErrorException(JObject error)
+        public ReturnAsErrorException(JObject error) : base(error.ToString())
             => Error = Result.Err(error);
 
         public ReturnAsErrorException(string message, string className)
+            : base($"[{className}] {message}")
         {
             var result = new
             {
@@ -466,5 +467,7 @@ namespace Microsoft.WebAssembly.Diagnostics
                     }
                 }));
         }
+
+        public override string ToString() => $"Error object: {Error}. {base.ToString()}";
     }
 }
diff --git a/src/mono/wasm/debugger/BrowserDebugProxy/MonoProxy.cs b/src/mono/wasm/debugger/BrowserDebugProxy/MonoProxy.cs
index 565c2bcb841..581f7ef5cf6 100644
--- a/src/mono/wasm/debugger/BrowserDebugProxy/MonoProxy.cs
+++ b/src/mono/wasm/debugger/BrowserDebugProxy/MonoProxy.cs
@@ -51,7 +51,7 @@ namespace Microsoft.WebAssembly.Diagnostics
 
         internal Task<Result> SendMonoCommand(SessionId id, MonoCommands cmd, CancellationToken token) => SendCommand(id, "Runtime.evaluate", JObject.FromObject(cmd), token);
 
-        internal void SendLog(SessionId sessionId, string message, CancellationToken token)
+        internal void SendLog(SessionId sessionId, string message, CancellationToken token, string type = "warning")
         {
             if (!contexts.TryGetValue(sessionId, out ExecutionContext context))
                 return;
@@ -68,7 +68,7 @@ namespace Microsoft.WebAssembly.Diagnostics
             SendEvent(id, "Log.entryAdded", o, token);*/
             var o = JObject.FromObject(new
             {
-                type = "warning",
+                type,
                 args = new JArray(JObject.FromObject(new
                                 {
                                     type = "string",
@@ -139,7 +139,7 @@ namespace Microsoft.WebAssembly.Diagnostics
 
                 case "Runtime.executionContextCreated":
                     {
-                        SendEvent(sessionId, method, args, token);
+                        await SendEvent(sessionId, method, args, token);
                         JToken ctx = args?["context"];
                         var aux_data = ctx?["auxData"] as JObject;
                         int id = ctx["id"].Value<int>();
@@ -805,14 +805,22 @@ namespace Microsoft.WebAssembly.Diagnostics
                     if (retValue?["value"]?.Value<bool>() == true)
                         return true;
                 }
-                else if (retValue?["value"]?.Type != JTokenType.Null)
+                else if (retValue?["value"] != null && // null object, missing value
+                         retValue?["value"]?.Type != JTokenType.Null)
+                {
                     return true;
+                }
+            }
+            catch (ReturnAsErrorException raee)
+            {
+                logger.LogDebug($"Unable to evaluate breakpoint condition '{condition}': {raee}");
+                SendLog(sessionId, $"Unable to evaluate breakpoint condition '{condition}': {raee.Message}", token, type: "error");
+                bp.ConditionAlreadyEvaluatedWithError = true;
             }
             catch (Exception e)
             {
-                Log("info", $"Unable evaluate conditional breakpoint: {e} condition:{condition}");
+                Log("info", $"Unable to evaluate breakpoint condition '{condition}': {e}");
                 bp.ConditionAlreadyEvaluatedWithError = true;
-                return false;
             }
             return false;
         }
@@ -986,7 +994,7 @@ namespace Microsoft.WebAssembly.Diagnostics
                 await SendCommand(sessionId, "Debugger.resume", new JObject(), token);
                 return true;
             }
-            SendEvent(sessionId, "Debugger.paused", o, token);
+            await SendEvent(sessionId, "Debugger.paused", o, token);
 
             return true;
 
@@ -1103,7 +1111,7 @@ namespace Microsoft.WebAssembly.Diagnostics
                     foreach (SourceFile source in asm.Sources)
                     {
                         var scriptSource = JObject.FromObject(source.ToScriptSource(context.Id, context.AuxData));
-                        SendEvent(sessionId, "Debugger.scriptParsed", scriptSource, token);
+                        await SendEvent(sessionId, "Debugger.scriptParsed", scriptSource, token);
                     }
                     return asm.GetMethodByToken(method_token);
                 }
@@ -1333,7 +1341,7 @@ namespace Microsoft.WebAssembly.Diagnostics
         {
             JObject scriptSource = JObject.FromObject(source.ToScriptSource(context.Id, context.AuxData));
             Log("debug", $"sending {source.Url} {context.Id} {sessionId.sessionId}");
-            SendEvent(sessionId, "Debugger.scriptParsed", scriptSource, token);
+            await SendEvent(sessionId, "Debugger.scriptParsed", scriptSource, token);
 
             foreach (var req in context.BreakpointRequests.Values)
             {
@@ -1412,7 +1420,7 @@ namespace Microsoft.WebAssembly.Diagnostics
 
             DebugStore store = await LoadStore(sessionId, token);
             context.ready.SetResult(store);
-            SendEvent(sessionId, "Mono.runtimeReady", new JObject(), token);
+            await SendEvent(sessionId, "Mono.runtimeReady", new JObject(), token);
             context.SdbAgent.ResetStore(store);
             return store;
         }
@@ -1502,7 +1510,7 @@ namespace Microsoft.WebAssembly.Diagnostics
                 };
 
                 if (sendResolvedEvent)
-                    SendEvent(sessionId, "Debugger.breakpointResolved", JObject.FromObject(resolvedLocation), token);
+                    await SendEvent(sessionId, "Debugger.breakpointResolved", JObject.FromObject(resolvedLocation), token);
             }
 
             req.Locations.AddRange(breakpoints);
diff --git a/src/mono/wasm/debugger/BrowserDebugProxy/MonoSDBHelper.cs b/src/mono/wasm/debugger/BrowserDebugProxy/MonoSDBHelper.cs
index 793d3c980b9..f30d42e69de 100644
--- a/src/mono/wasm/debugger/BrowserDebugProxy/MonoSDBHelper.cs
+++ b/src/mono/wasm/debugger/BrowserDebugProxy/MonoSDBHelper.cs
@@ -2121,8 +2121,16 @@ namespace Microsoft.WebAssembly.Diagnostics
             using var localsDebuggerCmdReader = await SendDebuggerAgentCommand(CmdFrame.GetValues, commandParamsWriter, token);
             foreach (var var in varIds)
             {
-                var var_json = await CreateJObjectForVariableValue(localsDebuggerCmdReader, var.Name, false, -1, false, token);
-                locals.Add(var_json);
+                try
+                {
+                    var var_json = await CreateJObjectForVariableValue(localsDebuggerCmdReader, var.Name, false, -1, false, token);
+                    locals.Add(var_json);
+                }
+                catch (Exception ex)
+                {
+                    logger.LogDebug($"Failed to create value for local var {var}: {ex}");
+                    continue;
+                }
             }
             if (!method.Info.IsStatic())
             {
diff --git a/src/mono/wasm/debugger/DebuggerTestSuite/ArrayTests.cs b/src/mono/wasm/debugger/DebuggerTestSuite/ArrayTests.cs
index 438eceea378..a9e87746bd8 100644
--- a/src/mono/wasm/debugger/DebuggerTestSuite/ArrayTests.cs
+++ b/src/mono/wasm/debugger/DebuggerTestSuite/ArrayTests.cs
@@ -552,6 +552,8 @@ namespace DebuggerTests
         }
 
         [Fact]
+        [Trait("Category", "windows-failing")] // https://github.com/dotnet/runtime/issues/65742
+        [Trait("Category", "linux-failing")] // https://github.com/dotnet/runtime/issues/65742
         public async Task InvalidArrayId() => await CheckInspectLocalsAtBreakpointSite(
             "DebuggerTests.Container", "PlaceholderMethod", 1, "PlaceholderMethod",
             "window.setTimeout(function() { invoke_static_method ('[debugger-test] DebuggerTests.ArrayTestsClass:ObjectArrayMembers'); }, 1);",
diff --git a/src/mono/wasm/debugger/DebuggerTestSuite/DebuggerTestBase.cs b/src/mono/wasm/debugger/DebuggerTestSuite/DebuggerTestBase.cs
index d39c2c2c10b..aa61555ab22 100644
--- a/src/mono/wasm/debugger/DebuggerTestSuite/DebuggerTestBase.cs
+++ b/src/mono/wasm/debugger/DebuggerTestSuite/DebuggerTestBase.cs
@@ -90,14 +90,17 @@ namespace DebuggerTests
             {
                 chrome_path = FindChromePath();
                 if (!string.IsNullOrEmpty(chrome_path))
+                {
+                    chrome_path = Path.GetFullPath(chrome_path);
                     Console.WriteLine ($"** Using chrome from {chrome_path}");
+                }
                 else
                     throw new Exception("Could not find an installed Chrome to use");
             }
 
             return chrome_path;
 
-            string FindChromePath()
+            static string FindChromePath()
             {
                 string chrome_path_env_var = Environment.GetEnvironmentVariable("CHROME_PATH_FOR_DEBUGGER_TESTS");
                 if (!string.IsNullOrEmpty(chrome_path_env_var))
@@ -108,6 +111,15 @@ namespace DebuggerTests
                     Console.WriteLine ($"warning: Could not find CHROME_PATH_FOR_DEBUGGER_TESTS={chrome_path_env_var}");
                 }
 
+                // Look for a chrome installed in artifacts, for local runs
+                string baseDir = Path.Combine(Path.GetDirectoryName(typeof(DebuggerTestBase).Assembly.Location), "..", "..");
+                string path = Path.Combine(baseDir, "chrome", "chrome-linux", "chrome");
+                if (File.Exists(path))
+                    return path;
+                path = Path.Combine(baseDir, "chrome", "chrome-win", "chrome.exe");
+                if (File.Exists(path))
+                    return path;
+
                 return PROBE_LIST.FirstOrDefault(p => File.Exists(p));
             }
         }
diff --git a/src/mono/wasm/debugger/DebuggerTestSuite/DebuggerTestSuite.csproj b/src/mono/wasm/debugger/DebuggerTestSuite/DebuggerTestSuite.csproj
index 602f06cfc95..8f981735595 100644
--- a/src/mono/wasm/debugger/DebuggerTestSuite/DebuggerTestSuite.csproj
+++ b/src/mono/wasm/debugger/DebuggerTestSuite/DebuggerTestSuite.csproj
@@ -5,6 +5,17 @@
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <RunAnalyzers>false</RunAnalyzers>
     <IsTestProject>true</IsTestProject>
+    <VersionsPropsFile>$(MSBuildThisFileDirectory)..\..\BrowsersForTesting.props</VersionsPropsFile>
+    <BrowserHost Condition="$([MSBuild]::IsOSPlatform('windows'))">windows</BrowserHost>
+    <InstallChromeForDebuggerTests Condition="'$(InstallChromeForDebuggerTests)' == '' and '$(ContinuousIntegrationBuild)' != 'true' and Exists('/.dockerenv')">true</InstallChromeForDebuggerTests>
+  </PropertyGroup>
+
+  <Import Project="$(VersionsPropsFile)" />
+
+  <PropertyGroup>
+    <ChromeDir>$(ArtifactsBinDir)DebuggerTestSuite\chrome\</ChromeDir>
+    <ChromeStampDir>$(ArtifactsBinDir)DebuggerTestSuite\</ChromeStampDir>
+    <ChromeStampFile>$(ChromeStampDir).install-chrome-$(ChromiumRevision).stamp</ChromeStampFile>
   </PropertyGroup>
 
   <ItemGroup>
@@ -34,4 +45,32 @@
 
     <Copy SourceFiles="@(_FilesToCopy)" DestinationFiles="$(ArchiveDirForHelix)\%(TargetPath)\%(RecursiveDir)%(FileName)%(Extension)" />
   </Target>
+
+  <Target Name="DownloadAndInstallChrome"
+          AfterTargets="Build"
+          Condition="!Exists($(ChromeStampFile)) and '$(InstallChromeForDebuggerTests)' == 'true'">
+
+    <ItemGroup>
+      <_StampFile Include="$(ChromeStampDir).install-chrome*.stamp" />
+    </ItemGroup>
+
+    <Delete Files="@(_StampFile)" />
+    <RemoveDir Directories="$(ChromeDir)" />
+
+    <DownloadFile SourceUrl="$(ChromiumUrl)" DestinationFolder="$(ChromeDir)" SkipUnchangedFiles="true">
+      <Output TaskParameter="DownloadedFile" PropertyName="_DownloadedFile" />
+    </DownloadFile>
+    <Unzip SourceFiles="$(_DownloadedFile)" DestinationFolder="$(ChromeDir)" />
+
+    <PropertyGroup>
+      <_ChromeBinaryPath>$([MSBuild]::NormalizePath($(ChromeDir), $(ChromiumDirName), $(ChromiumBinaryName)))</_ChromeBinaryPath>
+    </PropertyGroup>
+
+    <Error Text="Cannot find chrome at $(_ChromeBinaryPath) in the downloaded copy"
+           Condition="!Exists($(_ChromeBinaryPath))" />
+
+    <Exec Command="chmod +x $(_ChromeBinaryPath)" Condition="!$([MSBuild]::IsOSPlatform('windows'))" />
+
+    <Touch Files="$(ChromeStampFile)" AlwaysCreate="true" />
+  </Target>
 </Project>
diff --git a/src/mono/wasm/debugger/DebuggerTestSuite/DevToolsClient.cs b/src/mono/wasm/debugger/DebuggerTestSuite/DevToolsClient.cs
index 7c5874df227..6eed6e177f9 100644
--- a/src/mono/wasm/debugger/DebuggerTestSuite/DevToolsClient.cs
+++ b/src/mono/wasm/debugger/DebuggerTestSuite/DevToolsClient.cs
@@ -18,6 +18,7 @@ namespace Microsoft.WebAssembly.Diagnostics
         ClientWebSocket socket;
         TaskCompletionSource _clientInitiatedClose = new TaskCompletionSource();
         TaskCompletionSource _shutdownRequested = new TaskCompletionSource();
+        readonly TaskCompletionSource<Exception> _failRequested = new();
         TaskCompletionSource _newSendTaskAvailable = new ();
         protected readonly ILogger logger;
 
@@ -65,6 +66,14 @@ namespace Microsoft.WebAssembly.Diagnostics
             }
         }
 
+        public void Fail(Exception exception)
+        {
+            if (_failRequested.Task.IsCompleted)
+                logger.LogError($"Fail requested again with {exception}");
+            else
+                _failRequested.TrySetResult(exception);
+        }
+
         async Task<string> ReadOne(CancellationToken token)
         {
             byte[] buff = new byte[4000];
@@ -172,7 +181,8 @@ namespace Microsoft.WebAssembly.Diagnostics
                 ReadOne(linkedCts.Token),
                 _newSendTaskAvailable.Task,
                 _clientInitiatedClose.Task,
-                _shutdownRequested.Task
+                _shutdownRequested.Task,
+                _failRequested.Task
             };
 
             // In case we had a Send called already
@@ -192,6 +202,9 @@ namespace Microsoft.WebAssembly.Diagnostics
                 if (_clientInitiatedClose.Task.IsCompleted)
                     return (RunLoopStopReason.ClientInitiatedClose, new TaskCanceledException("Proxy or the browser closed the connection"));
 
+                if (_failRequested.Task.IsCompleted)
+                    return (RunLoopStopReason.Exception, _failRequested.Task.Result);
+
                 if (_newSendTaskAvailable.Task.IsCompleted)
                 {
                     // Just needed to wake up. the new task has already
diff --git a/src/mono/wasm/debugger/DebuggerTestSuite/EvaluateOnCallFrameTests.cs b/src/mono/wasm/debugger/DebuggerTestSuite/EvaluateOnCallFrameTests.cs
index c38596af1e5..946dcbd394b 100644
--- a/src/mono/wasm/debugger/DebuggerTestSuite/EvaluateOnCallFrameTests.cs
+++ b/src/mono/wasm/debugger/DebuggerTestSuite/EvaluateOnCallFrameTests.cs
@@ -494,6 +494,8 @@ namespace DebuggerTests
 
 
         [Fact]
+        [Trait("Category", "windows-failing")] // https://github.com/dotnet/runtime/issues/65744
+        [Trait("Category", "linux-failing")] // https://github.com/dotnet/runtime/issues/65744
         public async Task EvaluateSimpleMethodCallsError() => await CheckInspectLocalsAtBreakpointSite(
             "DebuggerTests.EvaluateMethodTestsClass.TestEvaluate", "run", 9, "run",
             "window.setTimeout(function() { invoke_static_method ('[debugger-test] DebuggerTests.EvaluateMethodTestsClass:EvaluateMethods'); })",
diff --git a/src/mono/wasm/debugger/DebuggerTestSuite/Inspector.cs b/src/mono/wasm/debugger/DebuggerTestSuite/Inspector.cs
index 3a74ed70e78..cde3ef31145 100644
--- a/src/mono/wasm/debugger/DebuggerTestSuite/Inspector.cs
+++ b/src/mono/wasm/debugger/DebuggerTestSuite/Inspector.cs
@@ -29,6 +29,7 @@ namespace DebuggerTests
         public const string READY = "ready";
         public CancellationToken Token { get; }
         public InspectorClient Client { get; }
+        public bool DetectAndFailOnAssertions { get; set; } = true;
 
         private CancellationTokenSource _cancellationTokenSource;
 
@@ -184,8 +185,17 @@ namespace DebuggerTests
                     NotifyOf(READY, args);
                     break;
                 case "Runtime.consoleAPICalled":
-                    _logger.LogInformation(FormatConsoleAPICalled(args));
+                {
+                    string line = FormatConsoleAPICalled(args);
+                    _logger.LogInformation(line);
+                    if (DetectAndFailOnAssertions && line.Contains("console.error: * Assertion at"))
+                    {
+                        args["__forMethod"] = method;
+                        Client.Fail(new ArgumentException($"Assertion detected in the messages: {line}{Environment.NewLine}{args}"));
+                        return;
+                    }
                     break;
+                }
                 case "Inspector.detached":
                 case "Inspector.targetCrashed":
                 case "Inspector.targetReloadedAfterCrash":