diff --git a/js/src/shell/js.cpp b/js/src/shell/js.cpp
index 30787cdc2689..80b93612485c 100644
--- a/js/src/shell/js.cpp
+++ b/js/src/shell/js.cpp
@@ -4002,8 +4002,6 @@ static bool ShellBuildId(JS::BuildIdCharVector* buildId);
 static void WorkerMain(WorkerInput* input) {
   MOZ_ASSERT(input->parentRuntime);
 
-  auto mutexShutdown = mozilla::MakeScopeExit([] { Mutex::ShutDown(); });
-
   JSContext* cx = JS_NewContext(8L * 1024L * 1024L, 2L * 1024L * 1024L,
                                 input->parentRuntime);
   if (!cx) {
@@ -4303,8 +4301,6 @@ static void WatchdogMain(JSContext* cx) {
       }
     }
   }
-
-  Mutex::ShutDown();
 }
 
 static bool ScheduleWatchdog(JSContext* cx, double t) {
@@ -7129,8 +7125,6 @@ struct BufferStreamState {
 static ExclusiveWaitableData<BufferStreamState>* bufferStreamState;
 
 static void BufferStreamMain(BufferStreamJob* job) {
-  auto mutexShutdown = MakeScopeExit([] { Mutex::ShutDown(); });
-
   const uint8_t* bytes;
   size_t byteLength;
   JS::OptimizedEncodingListener* listener;
diff --git a/js/src/threading/Mutex.cpp b/js/src/threading/Mutex.cpp
index cc4dcc1a6a80..c762dd359001 100644
--- a/js/src/threading/Mutex.cpp
+++ b/js/src/threading/Mutex.cpp
@@ -17,9 +17,6 @@ MOZ_THREAD_LOCAL(js::Mutex*) js::Mutex::HeldMutexStack;
 /* static */
 bool js::Mutex::Init() { return HeldMutexStack.init(); }
 
-/* static */
-void js::Mutex::ShutDown() { MOZ_ASSERT(HeldMutexStack.get() == nullptr); }
-
 void js::Mutex::lock() {
   preLockChecks();
   impl_.lock();
diff --git a/js/src/threading/Mutex.h b/js/src/threading/Mutex.h
index 82ff21bd597c..c47660621cdb 100644
--- a/js/src/threading/Mutex.h
+++ b/js/src/threading/Mutex.h
@@ -51,10 +51,8 @@ class Mutex {
  public:
 #ifdef DEBUG
   static bool Init();
-  static void ShutDown();
 #else
   static bool Init() { return true; }
-  static void ShutDown() {}
 #endif
 
   explicit Mutex(const MutexId& id)
diff --git a/js/src/vm/HelperThreads.cpp b/js/src/vm/HelperThreads.cpp
index ebe5ecdc55f2..4807ac1756c8 100644
--- a/js/src/vm/HelperThreads.cpp
+++ b/js/src/vm/HelperThreads.cpp
@@ -2089,7 +2089,6 @@ void HelperThread::ThreadMain(void* arg) {
   mozilla::recordreplay::AutoDisallowThreadEvents d;
 
   static_cast<HelperThread*>(arg)->threadLoop();
-  Mutex::ShutDown();
 }
 
 void HelperThread::handleWasmTier1Workload(AutoLockHelperThreadState& locked) {
diff --git a/js/src/vm/Initialization.cpp b/js/src/vm/Initialization.cpp
index 7b1fa9679288..0e9c783ff8ae 100644
--- a/js/src/vm/Initialization.cpp
+++ b/js/src/vm/Initialization.cpp
@@ -223,8 +223,6 @@ JS_PUBLIC_API void JS_ShutDown(void) {
 
   js::wasm::ShutDown();
 
-  js::Mutex::ShutDown();
-
   // The only difficult-to-address reason for the restriction that you can't
   // call JS_Init/stuff/JS_ShutDown multiple times is the Windows PRMJ
   // NowInit initialization code, which uses PR_CallOnce to initialize the