diff --git a/dom/workers/WorkerThread.cpp b/dom/workers/WorkerThread.cpp
index a04a1efedd90..f7631055dc85 100644
--- a/dom/workers/WorkerThread.cpp
+++ b/dom/workers/WorkerThread.cpp
@@ -95,8 +95,6 @@ SafeRefPtr<WorkerThread> WorkerThread::Create(
     NS_WARNING("Failed to create new thread!");
     return nullptr;
   }
-  thread->mAbstractThread = AbstractThread::CreateXPCOMThreadWrapper(
-      thread.unsafeGetRawPtr(), false /* aRequireTailDispatch */);
 
   return thread;
 }
@@ -334,14 +332,6 @@ PerformanceCounter* WorkerThread::GetPerformanceCounter(
   return nullptr;
 }
 
-NS_IMETHODIMP
-WorkerThread::Shutdown() {
-  MOZ_ALWAYS_SUCCEEDS(nsThread::Shutdown());
-  // We need to break the cycle.
-  mAbstractThread = nullptr;
-  return NS_OK;
-}
-
 NS_IMPL_ISUPPORTS(WorkerThread::Observer, nsIThreadObserver)
 
 NS_IMETHODIMP
diff --git a/dom/workers/WorkerThread.h b/dom/workers/WorkerThread.h
index 20c26f387c3f..78ac19eaae3f 100644
--- a/dom/workers/WorkerThread.h
+++ b/dom/workers/WorkerThread.h
@@ -18,7 +18,6 @@
 class nsIRunnable;
 
 namespace mozilla {
-class AbstractThread;
 namespace dom {
 
 class WorkerRunnable;
@@ -57,12 +56,6 @@ class WorkerThread final : public nsThread {
   // Protected by nsThread::mLock and waited on with mWorkerPrivateCondVar.
   uint32_t mOtherThreadsDispatchingViaEventTarget;
 
-  // We create an AbstractThread for this current nsThread instance in order to
-  // support direct task dispatching. Direct tasks work in a similar fashion to
-  // microtasks and allow an IPDL MozPromise to behave like JS promise.
-  // An AbstractThread only need to exist on the current thread for Direct Task
-  // dispatch to be available.
-  RefPtr<AbstractThread> mAbstractThread;
 #ifdef DEBUG
   // Protected by nsThread::mLock.
   bool mAcceptingNonWorkerRunnables;
@@ -90,8 +83,6 @@ class WorkerThread final : public nsThread {
 
   PerformanceCounter* GetPerformanceCounter(nsIRunnable* aEvent) const override;
 
-  NS_IMETHODIMP Shutdown() override;
-
   NS_INLINE_DECL_REFCOUNTING_INHERITED(WorkerThread, nsThread)
 
  private: