--- a/toolkit/components/social/test/browser/browser_frameworker.js
+++ b/toolkit/components/social/test/browser/browser_frameworker.js
@@ -461,71 +461,75 @@ let tests = {
         }
         ioService.offline = false;
       }
       ioService.offline = true;
     }
   },
   
   testMissingWorker: function(cbnext) {
+    let worker = getFrameWorkerHandle(url, undefined, "testMissingWorker");
     Services.obs.addObserver(function handleError() {
       Services.obs.removeObserver(handleError, "social:frameworker-error");
         ok(true, "social:frameworker-error was handled");
+        worker.terminate();
         cbnext();
     }, 'social:frameworker-error', false);
     // don't ever create this file!  We want a 404.
     let url = "https://example.com/browser/toolkit/components/social/test/browser/worker_is_missing.js";
-    let worker = getFrameWorkerHandle(url, undefined, "testMissingWorker");
     worker.port.onmessage = function(e) {
       ok(false, "social:frameworker-error was handled");
       cbnext();
     }
   },
 
   testNoConnectWorker: function(cbnext) {
+    let worker = getFrameWorkerHandle(makeWorkerUrl(function () {}),
+                                      undefined, "testNoConnectWorker");
     Services.obs.addObserver(function handleError() {
       Services.obs.removeObserver(handleError, "social:frameworker-error");
         ok(true, "social:frameworker-error was handled");
+        worker.terminate();
         cbnext();
     }, 'social:frameworker-error', false);
-    let worker = getFrameWorkerHandle(makeWorkerUrl(function () {}),
-                                      undefined, "testNoConnectWorker");
     worker.port.onmessage = function(e) {
       ok(false, "social:frameworker-error was handled");
       cbnext();
     }
   },
 
   testEmptyWorker: function(cbnext) {
+    let worker = getFrameWorkerHandle("data:application/javascript;charset=utf-8,",
+                                      undefined, "testEmptyWorker");
     Services.obs.addObserver(function handleError() {
       Services.obs.removeObserver(handleError, "social:frameworker-error");
         ok(true, "social:frameworker-error was handled");
+        worker.terminate();
         cbnext();
     }, 'social:frameworker-error', false);
-    let worker = getFrameWorkerHandle("data:application/javascript;charset=utf-8,",
-                                      undefined, "testEmptyWorker");
     worker.port.onmessage = function(e) {
       ok(false, "social:frameworker-error was handled");
       cbnext();
     }
   },
 
   testWorkerConnectError: function(cbnext) {
+    let worker = getFrameWorkerHandle(makeWorkerUrl(run),
+                                      undefined, "testWorkerConnectError");
     Services.obs.addObserver(function handleError() {
       Services.obs.removeObserver(handleError, "social:frameworker-error");
         ok(true, "social:frameworker-error was handled");
+        worker.terminate();
         cbnext();
     }, 'social:frameworker-error', false);
     let run = function () {
       onconnect = function(e) {
         throw new Error("worker failure");
       }
     }
-    let worker = getFrameWorkerHandle(makeWorkerUrl(run),
-                                      undefined, "testWorkerConnectError");
     worker.port.onmessage = function(e) {
       ok(false, "social:frameworker-error was handled");
       cbnext();
     }
   },
 
   testReloadAndNewPort: function(cbnext) {
     let run = function () {