--- a/gfx/layers/wr/WebRenderBridgeParent.cpp
+++ b/gfx/layers/wr/WebRenderBridgeParent.cpp
@@ -893,27 +893,27 @@ WebRenderBridgeParent::RecvEmptyTransact
     // transactions inflight, then set sendDidComposite to false because we will
     // send the DidComposite message after the composite occurs.
     // If there are no pending transactions and we're not going to do a
     // composite, then we leave sendDidComposite as true so we just send
     // the DidComposite notification now.
     sendDidComposite = false;
   }
 
-  HoldPendingTransactionId(WrEpoch(), aTransactionId, aRefreshStartTime, aTxnStartTime, aFwdTime);
+  HoldPendingTransactionId(mWrEpoch, aTransactionId, aRefreshStartTime, aTxnStartTime, aFwdTime);
 
   if (scheduleComposite) {
     ScheduleGenerateFrame();
   } else if (sendDidComposite) {
     // The only thing in the pending transaction id queue should be the entry
     // we just added, and now we're going to pretend we rendered it
     MOZ_ASSERT(mPendingTransactionIds.size() == 1);
     if (CompositorBridgeParent* cbp = GetRootCompositorBridgeParent()) {
       TimeStamp now = TimeStamp::Now();
-      cbp->NotifyPipelineRendered(mPipelineId, WrEpoch(), now, now);
+      cbp->NotifyPipelineRendered(mPipelineId, mWrEpoch, now, now);
     }
   }
 
   if (ShouldParentObserveEpoch()) {
     mCompositorBridge->ObserveLayerUpdate(GetLayersId(), GetChildLayerObserverEpoch(), true);
   }
 
   return IPC_OK();

--- a/gfx/layers/wr/WebRenderBridgeParent.h
+++ b/gfx/layers/wr/WebRenderBridgeParent.h
@@ -56,17 +56,16 @@ public:
                         RefPtr<AsyncImagePipelineManager>&& aImageMgr,
                         RefPtr<CompositorAnimationStorage>&& aAnimStorage,
                         TimeDuration aVsyncRate);
 
   static WebRenderBridgeParent* CreateDestroyed(const wr::PipelineId& aPipelineId);
 
   wr::PipelineId PipelineId() { return mPipelineId; }
   already_AddRefed<wr::WebRenderAPI> GetWebRenderAPI() { return do_AddRef(mApi); }
-  wr::Epoch WrEpoch() const { return mWrEpoch; }
   AsyncImagePipelineManager* AsyncImageManager() { return mAsyncImageManager; }
   CompositorVsyncScheduler* CompositorScheduler() { return mCompositorScheduler.get(); }
 
   mozilla::ipc::IPCResult RecvNewCompositable(const CompositableHandle& aHandle,
                                               const TextureInfo& aInfo) override;
   mozilla::ipc::IPCResult RecvReleaseCompositable(const CompositableHandle& aHandle) override;
 
   mozilla::ipc::IPCResult RecvCreate(const gfx::IntSize& aSize) override;