src/libraries/System.Net.WebSockets/src/Resources/Strings.resx:142

• [nitpick] The error message is unclear; consider rephrasing to "The timeout must be non-negative or Timeout.InfiniteTimeSpan." for better readability.

    <value>The timeout must be a value between non-negative or Timeout.InfiniteTimeSpan.</value>

src/libraries/System.Net.WebSockets/tests/System.Net.WebSockets.Tests.csproj:11

• The project references WebSocketCreateTest.cs which does not exist; it should reference the actual test file (WebSocketStreamCreateTests.cs) to include the new tests and avoid compilation failures.

    <Compile Include="WebSocketCreateTest.cs" />

src/libraries/System.Net.WebSockets/ref/System.Net.WebSockets.cs:51

• The reference assembly declares a parameterless WebSocketStream constructor, but the implementation only defines a constructor taking a WebSocket parameter. This mismatch will cause API and compilation inconsistencies.

        private protected WebSocketStream() { }

src/libraries/System.Net.WebSockets/src/System/Net/WebSockets/WebSocketStream.cs:273

• The call to ConfigureAwait uses ConfigureAwaitOptions.SuppressThrowing, but ConfigureAwait expects a bool. Replace with ConfigureAwait(false) (or true if appropriate) to match the API.

                                await WebSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, null, ct).ConfigureAwait(ConfigureAwaitOptions.SuppressThrowing);