483878 - Parallel requests stuck via the http client transport over HTTP/2.

jetty-client/src/main/java/org/eclipse/jetty/client/MultiplexHttpDestination.java

@@ -119,6 +119,12 @@ public abstract class MultiplexHttpDestination<C extends Connection> extends Htt
         return true;
     }
 
+    @Override
+    public void release(Connection connection)
+    {
+        send();
+    }
+
     @Override
     public void close()
     {

jetty-http2/http2-http-client-transport/src/main/java/org/eclipse/jetty/http2/client/http/HttpConnectionOverHTTP2.java

@@ -57,6 +57,7 @@ public class HttpConnectionOverHTTP2 extends HttpConnection
     protected void release(HttpChannel channel)
     {
         channels.remove(channel);
+        getHttpDestination().release(this);
     }
 
     @Override