diff --git a/dom/base/nsIGlobalObject.cpp b/dom/base/nsIGlobalObject.cpp
index 9d17b16e50b2..6b5ce7b88381 100644
--- a/dom/base/nsIGlobalObject.cpp
+++ b/dom/base/nsIGlobalObject.cpp
@@ -182,6 +182,14 @@ Maybe<ClientInfo> nsIGlobalObject::GetClientInfo() const {
   return Maybe<ClientInfo>();
 }
 
+Maybe<nsID> nsIGlobalObject::GetAgentClusterId() const {
+  Maybe<ClientInfo> ci = GetClientInfo();
+  if (ci.isSome()) {
+    return ci.value().AgentClusterId();
+  }
+  return Nothing();
+}
+
 Maybe<ServiceWorkerDescriptor> nsIGlobalObject::GetController() const {
   // By default globals do not have a service worker controller.  Only real
   // window and worker globals can currently be controlled as a client.
diff --git a/dom/base/nsIGlobalObject.h b/dom/base/nsIGlobalObject.h
index ccaf46003d2c..b6f9cb233189 100644
--- a/dom/base/nsIGlobalObject.h
+++ b/dom/base/nsIGlobalObject.h
@@ -144,6 +144,8 @@ class nsIGlobalObject : public nsISupports,
 
   virtual mozilla::Maybe<mozilla::dom::ClientInfo> GetClientInfo() const;
 
+  virtual mozilla::Maybe<nsID> GetAgentClusterId() const;
+
   virtual mozilla::Maybe<mozilla::dom::ServiceWorkerDescriptor> GetController()
       const;
 
diff --git a/dom/broadcastchannel/BroadcastChannel.cpp b/dom/broadcastchannel/BroadcastChannel.cpp
index 5be78d743944..eab817207705 100644
--- a/dom/broadcastchannel/BroadcastChannel.cpp
+++ b/dom/broadcastchannel/BroadcastChannel.cpp
@@ -353,10 +353,7 @@ void BroadcastChannel::PostMessage(JSContext* aCx,
   nsCOMPtr<nsIGlobalObject> global = GetOwnerGlobal();
   MOZ_ASSERT(global);
   if (global) {
-    Maybe<ClientInfo> clientInfo = global->GetClientInfo();
-    if (clientInfo) {
-      agentClusterId = clientInfo->AgentClusterId();
-    }
+    agentClusterId = global->GetAgentClusterId();
   }
 
   RefPtr<SharedMessageBody> data = new SharedMessageBody(
diff --git a/dom/ipc/SharedMessageBody.cpp b/dom/ipc/SharedMessageBody.cpp
index 0a1d32df6742..6b3cb11d42a4 100644
--- a/dom/ipc/SharedMessageBody.cpp
+++ b/dom/ipc/SharedMessageBody.cpp
@@ -71,13 +71,10 @@ void SharedMessageBody::Read(JSContext* aCx,
     nsIGlobalObject* global = xpc::CurrentNativeGlobal(aCx);
     MOZ_ASSERT(global);
 
-    Maybe<ClientInfo> clientInfo = global->GetClientInfo();
-    if (clientInfo) {
-      Maybe<nsID> agentClusterId = clientInfo->AgentClusterId();
-      if (agentClusterId.isSome() &&
-          mAgentClusterId.value().Equals(agentClusterId.value())) {
-        cloneDataPolicy.allowIntraClusterClonableSharedObjects();
-      }
+    Maybe<nsID> agentClusterId = global->GetAgentClusterId();
+    if (agentClusterId.isSome() &&
+        mAgentClusterId.value().Equals(agentClusterId.value())) {
+      cloneDataPolicy.allowIntraClusterClonableSharedObjects();
     }
   }
 
diff --git a/dom/media/webaudio/AudioWorkletGlobalScope.cpp b/dom/media/webaudio/AudioWorkletGlobalScope.cpp
index b672dbbcca8d..945cf23747ad 100644
--- a/dom/media/webaudio/AudioWorkletGlobalScope.cpp
+++ b/dom/media/webaudio/AudioWorkletGlobalScope.cpp
@@ -33,7 +33,7 @@ NS_IMPL_ADDREF_INHERITED(AudioWorkletGlobalScope, WorkletGlobalScope)
 NS_IMPL_RELEASE_INHERITED(AudioWorkletGlobalScope, WorkletGlobalScope)
 
 AudioWorkletGlobalScope::AudioWorkletGlobalScope(AudioWorkletImpl* aImpl)
-    : mImpl(aImpl) {}
+    : WorkletGlobalScope(aImpl->GetAgentClusterId()), mImpl(aImpl) {}
 
 bool AudioWorkletGlobalScope::WrapGlobalObject(
     JSContext* aCx, JS::MutableHandle<JSObject*> aReflector) {
diff --git a/dom/messagechannel/MessagePort.cpp b/dom/messagechannel/MessagePort.cpp
index 519c49a2947c..5e1830453b26 100644
--- a/dom/messagechannel/MessagePort.cpp
+++ b/dom/messagechannel/MessagePort.cpp
@@ -332,10 +332,7 @@ void MessagePort::PostMessage(JSContext* aCx, JS::Handle<JS::Value> aMessage,
   Maybe<nsID> agentClusterId;
   nsCOMPtr<nsIGlobalObject> global = GetOwnerGlobal();
   if (global) {
-    Maybe<ClientInfo> clientInfo = global->GetClientInfo();
-    if (clientInfo) {
-      agentClusterId = clientInfo->AgentClusterId();
-    }
+    agentClusterId = global->GetAgentClusterId();
   }
 
   RefPtr<SharedMessageBody> data = new SharedMessageBody(
diff --git a/dom/worklet/WorkletGlobalScope.cpp b/dom/worklet/WorkletGlobalScope.cpp
index 3ffbadd7ff93..f4e4e86f0d12 100644
--- a/dom/worklet/WorkletGlobalScope.cpp
+++ b/dom/worklet/WorkletGlobalScope.cpp
@@ -36,8 +36,8 @@ NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(WorkletGlobalScope)
   NS_INTERFACE_MAP_ENTRY(WorkletGlobalScope)
 NS_INTERFACE_MAP_END
 
-WorkletGlobalScope::WorkletGlobalScope()
-    : mCreationTimeStamp(TimeStamp::Now()) {}
+WorkletGlobalScope::WorkletGlobalScope(const Maybe<nsID>& aAgentClusterId)
+    : mCreationTimeStamp(TimeStamp::Now()), mAgentClusterId(aAgentClusterId) {}
 
 WorkletGlobalScope::~WorkletGlobalScope() = default;
 
diff --git a/dom/worklet/WorkletGlobalScope.h b/dom/worklet/WorkletGlobalScope.h
index dc09a3c6080e..b7a5dbb1c7a1 100644
--- a/dom/worklet/WorkletGlobalScope.h
+++ b/dom/worklet/WorkletGlobalScope.h
@@ -9,6 +9,7 @@
 
 #include "mozilla/Attributes.h"
 #include "mozilla/ErrorResult.h"
+#include "mozilla/Maybe.h"
 #include "mozilla/TimeStamp.h"
 #include "mozilla/dom/BindingDeclarations.h"
 #include "nsDOMNavigationTiming.h"
@@ -37,7 +38,7 @@ class WorkletGlobalScope : public nsIGlobalObject, public nsWrapperCache {
   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(WorkletGlobalScope)
 
-  WorkletGlobalScope();
+  explicit WorkletGlobalScope(const Maybe<nsID>& aAgentClusterId);
 
   nsIGlobalObject* GetParentObject() const { return nullptr; }
 
@@ -64,12 +65,15 @@ class WorkletGlobalScope : public nsIGlobalObject, public nsWrapperCache {
     return duration.ToMilliseconds();
   }
 
+  Maybe<nsID> GetAgentClusterId() const override { return mAgentClusterId; }
+
  protected:
   ~WorkletGlobalScope();
   ;
 
  private:
   TimeStamp mCreationTimeStamp;
+  Maybe<nsID> mAgentClusterId;
   RefPtr<Console> mConsole;
 };
 
diff --git a/dom/worklet/WorkletImpl.cpp b/dom/worklet/WorkletImpl.cpp
index af18294b7aa0..b8cc204c8a79 100644
--- a/dom/worklet/WorkletImpl.cpp
+++ b/dom/worklet/WorkletImpl.cpp
@@ -40,6 +40,10 @@ WorkletImpl::WorkletImpl(nsPIDOMWindowInner* aWindow, nsIPrincipal* aPrincipal)
       mTerminated(false) {
   Unused << NS_WARN_IF(
       NS_FAILED(ipc::PrincipalToPrincipalInfo(mPrincipal, &mPrincipalInfo)));
+
+  if (aWindow->GetDocGroup()) {
+    mAgentClusterId.emplace(aWindow->GetDocGroup()->AgentClusterId());
+  }
 }
 
 WorkletImpl::~WorkletImpl() {
diff --git a/dom/worklet/WorkletImpl.h b/dom/worklet/WorkletImpl.h
index d879095b6ee4..f976aeb831f1 100644
--- a/dom/worklet/WorkletImpl.h
+++ b/dom/worklet/WorkletImpl.h
@@ -8,6 +8,7 @@
 #define mozilla_dom_worklet_WorkletImpl_h
 
 #include "MainThreadUtils.h"
+#include "mozilla/Maybe.h"
 #include "mozilla/OriginAttributes.h"
 #include "mozilla/ipc/PBackgroundSharedTypes.h"
 
@@ -74,6 +75,8 @@ class WorkletImpl {
   }
   const ipc::PrincipalInfo& PrincipalInfo() const { return mPrincipalInfo; }
 
+  const Maybe<nsID>& GetAgentClusterId() const { return mAgentClusterId; }
+
  protected:
   WorkletImpl(nsPIDOMWindowInner* aWindow, nsIPrincipal* aPrincipal);
   virtual ~WorkletImpl();
@@ -93,6 +96,8 @@ class WorkletImpl {
 
   // Execution thread only.
   RefPtr<dom::WorkletGlobalScope> mGlobalScope;
+
+  Maybe<nsID> mAgentClusterId;
 };
 
 }  // namespace mozilla
diff --git a/layout/style/PaintWorkletGlobalScope.cpp b/layout/style/PaintWorkletGlobalScope.cpp
index 07e2b6d50333..4f8f9558a5c2 100644
--- a/layout/style/PaintWorkletGlobalScope.cpp
+++ b/layout/style/PaintWorkletGlobalScope.cpp
@@ -15,7 +15,7 @@ namespace mozilla {
 namespace dom {
 
 PaintWorkletGlobalScope::PaintWorkletGlobalScope(PaintWorkletImpl* aImpl)
-    : mImpl(aImpl) {}
+    : WorkletGlobalScope(aImpl->GetAgentClusterId()), mImpl(aImpl) {}
 
 bool PaintWorkletGlobalScope::WrapGlobalObject(
     JSContext* aCx, JS::MutableHandle<JSObject*> aReflector) {