--- a/dom/base/DOMPreferences.cpp
+++ b/dom/base/DOMPreferences.cpp
@@ -31,24 +31,26 @@ PREF(DumpEnabled, "browser.dom.window.du
 /* static */ bool
 DOMPreferences::DumpEnabled()
 {
   return true;
 }
 #endif
 
 PREF(ImageBitmapExtensionsEnabled, "canvas.imagebitmap_extensions.enabled")
+PREF(DOMCachesEnabled, "dom.caches.enabled")
 
 #undef PREF
 
 #define PREF_WEBIDL(name)                              \
   /* static */ bool                                    \
   DOMPreferences::name(JSContext* aCx, JSObject* aObj) \
   {                                                    \
     return DOMPreferences::name();                     \
   }
 
 PREF_WEBIDL(ImageBitmapExtensionsEnabled)
+PREF_WEBIDL(DOMCachesEnabled)
 
 #undef PREF_WEBIDL
 
 } // dom namespace
 } // mozilla namespace

--- a/dom/base/DOMPreferences.h
+++ b/dom/base/DOMPreferences.h
@@ -14,14 +14,18 @@ class DOMPreferences final
 {
 public:
   // Returns true if the browser.dom.window.dump.enabled pref is set.
   static bool DumpEnabled();
 
   // Returns true if the canvas.imagebitmap_extensions.enabled pref is set.
   static bool ImageBitmapExtensionsEnabled();
   static bool ImageBitmapExtensionsEnabled(JSContext* aCx, JSObject* aObj);
+
+  // Returns true if the dom.caches.enabled pref is set.
+  static bool DOMCachesEnabled();
+  static bool DOMCachesEnabled(JSContext* aCx, JSObject* aObj);
 };
 
 } // dom namespace
 } // mozilla namespace
 
 #endif // mozilla_dom_DOMPreferences_h

--- a/dom/base/nsGlobalWindowInner.h
+++ b/dom/base/nsGlobalWindowInner.h
@@ -32,16 +32,17 @@
 #include "nsIScriptObjectPrincipal.h"
 #include "nsITimer.h"
 #include "nsIDOMModalContentWindow.h"
 #include "mozilla/EventListenerManager.h"
 #include "nsIPrincipal.h"
 #include "nsSize.h"
 #include "mozilla/FlushType.h"
 #include "prclist.h"
+#include "mozilla/dom/DOMPreferences.h"
 #include "mozilla/dom/BindingDeclarations.h"
 #include "mozilla/dom/StorageEvent.h"
 #include "mozilla/dom/StorageEventBinding.h"
 #include "mozilla/dom/UnionTypes.h"
 #include "mozilla/ErrorResult.h"
 #include "nsFrameMessageManager.h"
 #include "mozilla/Attributes.h"
 #include "mozilla/GuardObjects.h"

--- a/dom/cache/Cache.cpp
+++ b/dom/cache/Cache.cpp
@@ -12,16 +12,17 @@
 #include "mozilla/dom/PromiseNativeHandler.h"
 #include "mozilla/dom/Response.h"
 #include "mozilla/dom/WorkerPrivate.h"
 #include "mozilla/dom/CacheBinding.h"
 #include "mozilla/dom/cache/AutoUtils.h"
 #include "mozilla/dom/cache/CacheChild.h"
 #include "mozilla/dom/cache/CacheWorkerHolder.h"
 #include "mozilla/dom/cache/ReadStream.h"
+#include "mozilla/dom/DOMPreferences.h"
 #include "mozilla/ErrorResult.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/Unused.h"
 #include "nsIGlobalObject.h"
 
 namespace mozilla {
 namespace dom {
 namespace cache {
@@ -512,39 +513,16 @@ Cache::Keys(JSContext* aCx, const Option
     if (NS_WARN_IF(aRv.Failed())) {
       return nullptr;
     }
   }
 
   return ExecuteOp(args, aRv);
 }
 
-// static
-bool
-Cache::PrefEnabled(JSContext* aCx, JSObject* aObj)
-{
-  using mozilla::dom::workers::WorkerPrivate;
-  using mozilla::dom::workers::GetWorkerPrivateFromContext;
-
-  // If we're on the main thread, then check the pref directly.
-  if (NS_IsMainThread()) {
-    bool enabled = false;
-    Preferences::GetBool("dom.caches.enabled", &enabled);
-    return enabled;
-  }
-
-  // Otherwise check the pref via the work private helper
-  WorkerPrivate* workerPrivate = GetWorkerPrivateFromContext(aCx);
-  if (!workerPrivate) {
-    return false;
-  }
-
-  return workerPrivate->DOMCachesEnabled();
-}
-
 nsISupports*
 Cache::GetParentObject() const
 {
   return mGlobal;
 }
 
 JSObject*
 Cache::WrapObject(JSContext* aContext, JS::Handle<JSObject*> aGivenProto)

--- a/dom/cache/Cache.h
+++ b/dom/cache/Cache.h
@@ -63,18 +63,16 @@ public:
   already_AddRefed<Promise>
   Delete(JSContext* aCx, const RequestOrUSVString& aRequest,
          const CacheQueryOptions& aOptions, ErrorResult& aRv);
   already_AddRefed<Promise>
   Keys(JSContext* aCx, const Optional<RequestOrUSVString>& aRequest,
        const CacheQueryOptions& aParams, ErrorResult& aRv);
 
   // binding methods
-  static bool PrefEnabled(JSContext* aCx, JSObject* aObj);
-
   nsISupports* GetParentObject() const;
   virtual JSObject* WrapObject(JSContext* aContext, JS::Handle<JSObject*> aGivenProto) override;
 
   // Called when CacheChild actor is being destroyed
   void DestroyInternal(CacheChild* aActor);
 
   // TypeUtils methods
   virtual nsIGlobalObject*

--- a/dom/cache/CacheStorage.cpp
+++ b/dom/cache/CacheStorage.cpp
@@ -440,23 +440,16 @@ CacheStorage::Keys(ErrorResult& aRv)
   entry->mArgs = StorageKeysArgs();
 
   RunRequest(Move(entry));
 
   return promise.forget();
 }
 
 // static
-bool
-CacheStorage::PrefEnabled(JSContext* aCx, JSObject* aObj)
-{
-  return Cache::PrefEnabled(aCx, aObj);
-}
-
-// static
 already_AddRefed<CacheStorage>
 CacheStorage::Constructor(const GlobalObject& aGlobal,
                           CacheStorageNamespace aNamespace,
                           nsIPrincipal* aPrincipal, ErrorResult& aRv)
 {
   if (NS_WARN_IF(!NS_IsMainThread())) {
     aRv.Throw(NS_ERROR_FAILURE);
     return nullptr;

--- a/dom/cache/CacheStorage.h
+++ b/dom/cache/CacheStorage.h
@@ -68,18 +68,16 @@ public:
   already_AddRefed<Promise> Keys(ErrorResult& aRv);
 
   // chrome-only webidl interface methods
   static already_AddRefed<CacheStorage>
   Constructor(const GlobalObject& aGlobal, CacheStorageNamespace aNamespace,
               nsIPrincipal* aPrincipal, ErrorResult& aRv);
 
   // binding methods
-  static bool PrefEnabled(JSContext* aCx, JSObject* aObj);
-
   nsISupports* GetParentObject() const;
   virtual JSObject* WrapObject(JSContext* aContext, JS::Handle<JSObject*> aGivenProto) override;
 
   // Called when CacheStorageChild actor is being destroyed
   void DestroyInternal(CacheStorageChild* aActor);
 
   // TypeUtils methods
   virtual nsIGlobalObject* GetGlobalObject() const override;

--- a/dom/webidl/Cache.webidl
+++ b/dom/webidl/Cache.webidl
@@ -6,17 +6,17 @@
  * The origin of this IDL file is
  * http://slightlyoff.github.io/ServiceWorker/spec/service_worker/index.html
  *
  */
 
 // https://slightlyoff.github.io/ServiceWorker/spec/service_worker/index.html#cache
 
 [Exposed=(Window,Worker),
- Func="mozilla::dom::cache::Cache::PrefEnabled"]
+ Func="mozilla::dom::DOMPreferences::DOMCachesEnabled"]
 interface Cache {
   [NewObject]
   Promise<Response> match(RequestInfo request, optional CacheQueryOptions options);
   [NewObject]
   Promise<sequence<Response>> matchAll(optional RequestInfo request, optional CacheQueryOptions options);
   [NewObject, NeedsCallerType]
   Promise<void> add(RequestInfo request);
   [NewObject, NeedsCallerType]

--- a/dom/webidl/CacheStorage.webidl
+++ b/dom/webidl/CacheStorage.webidl
@@ -9,17 +9,17 @@
  */
 
 // https://slightlyoff.github.io/ServiceWorker/spec/service_worker/index.html#cache-storage
 
 interface Principal;
 
 [Exposed=(Window,Worker),
  ChromeConstructor(CacheStorageNamespace namespace, Principal principal),
- Func="mozilla::dom::cache::CacheStorage::PrefEnabled"]
+ Func="mozilla::dom::DOMPreferences::DOMCachesEnabled"]
 interface CacheStorage {
   [NewObject]
   Promise<Response> match(RequestInfo request, optional CacheQueryOptions options);
   [NewObject]
   Promise<boolean> has(DOMString cacheName);
   [NewObject]
   Promise<Cache> open(DOMString cacheName);
   [NewObject]

--- a/dom/webidl/WindowOrWorkerGlobalScope.webidl
+++ b/dom/webidl/WindowOrWorkerGlobalScope.webidl
@@ -57,17 +57,17 @@ partial interface WindowOrWorkerGlobalSc
 partial interface WindowOrWorkerGlobalScope {
    // readonly attribute IDBFactory indexedDB;
    [Throws]
    readonly attribute IDBFactory? indexedDB;
 };
 
 // https://w3c.github.io/ServiceWorker/#self-caches
 partial interface WindowOrWorkerGlobalScope {
-  [Throws, Func="mozilla::dom::cache::CacheStorage::PrefEnabled", SameObject]
+  [Throws, Func="mozilla::dom::DOMPreferences::DOMCachesEnabled", SameObject]
   readonly attribute CacheStorage caches;
 };
 
 // Mozilla extensions
 partial interface WindowOrWorkerGlobalScope {
   // Extensions to ImageBitmap bits.
   // Bug 1141979 - [FoxEye] Extend ImageBitmap with interfaces to access its
   // underlying image data

--- a/dom/workers/WorkerPrefs.h
+++ b/dom/workers/WorkerPrefs.h
@@ -16,17 +16,16 @@
 //     macro in Workers.h.
 //   * The name of the function that updates the new value of a pref.
 //
 //   WORKER_PREF("foo.bar", UpdaterFunction)
 //
 //   * First argument is the name of the pref.
 //   * The name of the function that updates the new value of a pref.
 
-WORKER_SIMPLE_PREF("dom.caches.enabled", DOMCachesEnabled, DOM_CACHES)
 WORKER_SIMPLE_PREF("dom.caches.testing.enabled", DOMCachesTestingEnabled, DOM_CACHES_TESTING)
 WORKER_SIMPLE_PREF("dom.performance.enable_user_timing_logging", PerformanceLoggingEnabled, PERFORMANCE_LOGGING_ENABLED)
 WORKER_SIMPLE_PREF("dom.webnotifications.enabled", DOMWorkerNotificationEnabled, DOM_WORKERNOTIFICATION)
 WORKER_SIMPLE_PREF("dom.webnotifications.serviceworker.enabled", DOMServiceWorkerNotificationEnabled, DOM_SERVICEWORKERNOTIFICATION)
 WORKER_SIMPLE_PREF("dom.webnotifications.requireinteraction.enabled", DOMWorkerNotificationRIEnabled, DOM_WORKERNOTIFICATIONRI)
 WORKER_SIMPLE_PREF("dom.serviceWorkers.enabled", ServiceWorkersEnabled, SERVICEWORKERS_ENABLED)
 WORKER_SIMPLE_PREF("dom.serviceWorkers.testing.enabled", ServiceWorkersTestingEnabled, SERVICEWORKERS_TESTING_ENABLED)
 WORKER_SIMPLE_PREF("dom.storageManager.enabled", StorageManagerEnabled, STORAGEMANAGER_ENABLED)