diff --git a/dom/workers/SharedWorker.cpp b/dom/workers/SharedWorker.cpp
index 568844ac3fd8..f50c2687fe67 100644
--- a/dom/workers/SharedWorker.cpp
+++ b/dom/workers/SharedWorker.cpp
@@ -136,7 +136,6 @@ SharedWorker::Close()
 
   if (mMessagePort) {
     mMessagePort->Close();
-    mMessagePort = nullptr;
   }
 }
 
diff --git a/dom/workers/test/sharedWorker_ports.js b/dom/workers/test/sharedWorker_ports.js
index a0d29e29a2dc..64672e6abb27 100644
--- a/dom/workers/test/sharedWorker_ports.js
+++ b/dom/workers/test/sharedWorker_ports.js
@@ -17,6 +17,7 @@ onconnect = function(evt) {
                           test: (evtFromPort2.data.type == "connected"),
                           msg: "The original message received" });
         port.postMessage({type: "finish"});
+        close();
       }
     }
   }
diff --git a/dom/workers/test/test_sharedWorker_ports.html b/dom/workers/test/test_sharedWorker_ports.html
index 8233b3f71f38..32698ab5277e 100644
--- a/dom/workers/test/test_sharedWorker_ports.html
+++ b/dom/workers/test/test_sharedWorker_ports.html
@@ -28,6 +28,9 @@ sw1.port.onmessage = function(event) {
   }
 
   if (event.data.type == "finish") {
+    info("Finished!");
+    ok(sw1.port, "The port still exists");
+    sw1.port.foo = sw1; // Just a test to see if we leak.
     SimpleTest.finish();
   }
 }