diff --git a/jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/core/CloseStatus.java b/jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/core/CloseStatus.java
index 4c05283f3ac..375dac8ae54 100644
--- a/jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/core/CloseStatus.java
+++ b/jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/core/CloseStatus.java
@@ -175,16 +175,11 @@ public class CloseStatus
     // TODO consider defining a precedence for every CloseStatus, and change SessionState only if higher precedence
     public static boolean isOrdinary(CloseStatus closeStatus)
     {
-        switch (closeStatus.getCode())
-        {
-            case NORMAL:
-            case SHUTDOWN:
-            case NO_CODE:
-                return true;
-
-            default:
-                return false;
-        }
+        int code = closeStatus.getCode();
+        if (code == NORMAL || code == NO_CODE || code >= 3000)
+            return true;
+        else
+            return false;
     }
 
     public int getCode()
diff --git a/jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/core/internal/FrameFlusher.java b/jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/core/internal/FrameFlusher.java
index e69d59f9b44..e32c9f2c890 100644
--- a/jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/core/internal/FrameFlusher.java
+++ b/jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/core/internal/FrameFlusher.java
@@ -44,6 +44,8 @@ import org.eclipse.jetty.websocket.core.OpCode;
 import org.eclipse.jetty.websocket.core.WebSocketException;
 import org.eclipse.jetty.websocket.core.WebSocketWriteTimeoutException;
 
+import static org.eclipse.jetty.websocket.core.internal.WebSocketCoreSession.AbnormalCloseStatus;
+
 public class FrameFlusher extends IteratingCallback
 {
     public static final Frame FLUSH_FRAME = new Frame(OpCode.BINARY);
@@ -117,8 +119,7 @@ public class FrameFlusher extends IteratingCallback
                             else
                             {
                                 //fail all existing entries in the queue, and enqueue the close frame
-                                failedEntries = new ArrayList<>();
-                                failedEntries.addAll(queue);
+                                failedEntries = new ArrayList<>(queue);
                                 queue.clear();
                                 queue.offerFirst(entry);
                             }
@@ -152,9 +153,17 @@ public class FrameFlusher extends IteratingCallback
 
         if (failedEntries != null)
         {
+            WebSocketException failure = new WebSocketException("Flusher received abnormal CloseFrame: " + CloseStatus.codeString(closeStatus.getCode()));
+            if (closeStatus instanceof AbnormalCloseStatus)
+            {
+                Throwable cause = ((AbnormalCloseStatus)closeStatus).getCause();
+                if (cause != null)
+                    failure.addSuppressed(cause);
+            }
+
             for (Entry e : failedEntries)
             {
-                notifyCallbackFailure(e.callback, new WebSocketException(CloseStatus.codeString(closeStatus.getCode())));
+                notifyCallbackFailure(e.callback, failure);
             }
         }
 
diff --git a/jetty-websocket/websocket-core/src/test/java/org/eclipse/jetty/websocket/core/internal/FrameFlusherTest.java b/jetty-websocket/websocket-core/src/test/java/org/eclipse/jetty/websocket/core/internal/FrameFlusherTest.java
index 2cddce089f3..dee3c6860b8 100644
--- a/jetty-websocket/websocket-core/src/test/java/org/eclipse/jetty/websocket/core/internal/FrameFlusherTest.java
+++ b/jetty-websocket/websocket-core/src/test/java/org/eclipse/jetty/websocket/core/internal/FrameFlusherTest.java
@@ -199,47 +199,31 @@ public class FrameFlusherTest
         int maxGather = 8;
         FrameFlusher frameFlusher = new FrameFlusher(bufferPool, scheduler, generator, endPoint, bufferSize, maxGather);
 
-        // enqueue message before the error close
+        // Enqueue message before the error close.
         Frame frame1 = new Frame(OpCode.TEXT).setPayload("message before close").setFin(true);
-        LatchCallback callback1 = new LatchCallback();
-        assertTrue(frameFlusher.enqueue(frame1, callback1, false));
+        CountDownLatch failedFrame1 = new CountDownLatch(1);
+        Callback callbackFrame1 = Callback.from(()->{}, t->failedFrame1.countDown());
+        assertTrue(frameFlusher.enqueue(frame1, callbackFrame1, false));
 
-        // enqueue the close frame which should fail the previous frame as it is still in the queue
+        // Enqueue the close frame which should fail the previous frame as it is still in the queue.
         Frame closeFrame = new CloseStatus(CloseStatus.MESSAGE_TOO_LARGE).toFrame();
-        LatchCallback closeCallback = new LatchCallback();
-        assertTrue(frameFlusher.enqueue(closeFrame, closeCallback, false));
-        assertTrue(callback1.failure.await(1, TimeUnit.SECONDS));
+        CountDownLatch succeededCloseFrame = new CountDownLatch(1);
+        Callback closeFrameCallback = Callback.from(succeededCloseFrame::countDown, t->{});
+        assertTrue(frameFlusher.enqueue(closeFrame, closeFrameCallback, false));
+        assertTrue(failedFrame1.await(1, TimeUnit.SECONDS));
 
-        // any frames enqueued after this should fail
+        // Any frames enqueued after this should fail.
         Frame frame2 = new Frame(OpCode.TEXT).setPayload("message after close").setFin(true);
-        LatchCallback callback2 = new LatchCallback();
-        assertFalse(frameFlusher.enqueue(frame2, callback2, false));
-        assertTrue(callback2.failure.await(1, TimeUnit.SECONDS));
+        CountDownLatch failedFrame2 = new CountDownLatch(1);
+        Callback callbackFrame2 = Callback.from(()->{}, t->failedFrame2.countDown());
+        assertFalse(frameFlusher.enqueue(frame2, callbackFrame2, false));
+        assertTrue(failedFrame2.await(1, TimeUnit.SECONDS));
 
-        // iterating should succeed the close callback
+        // Iterating should succeed the close callback.
         frameFlusher.iterate();
-        assertTrue(closeCallback.success.await(1, TimeUnit.SECONDS));
+        assertTrue(succeededCloseFrame.await(1, TimeUnit.SECONDS));
     }
 
-    public static class LatchCallback implements Callback
-    {
-        public CountDownLatch success = new CountDownLatch(1);
-        public CountDownLatch failure = new CountDownLatch(1);
-
-        @Override
-        public void succeeded()
-        {
-            success.countDown();
-        }
-
-        @Override
-        public void failed(Throwable x)
-        {
-            failure.countDown();
-        }
-    }
-
-
     public static class CapturingEndPoint extends MockEndpoint
     {
         public Parser parser;