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diff --git a/dom/canvas/OffscreenCanvasDisplayHelper.h b/dom/canvas/OffscreenCanvasDisplayHelper.h
new file mode 100644
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+++ b/dom/canvas/OffscreenCanvasDisplayHelper.h
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+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef MOZILLA_DOM_OFFSCREENCANVASDISPLAYHELPER_H_
+#define MOZILLA_DOM_OFFSCREENCANVASDISPLAYHELPER_H_
+
+#include "ImageContainer.h"
+#include "GLContextTypes.h"
+#include "mozilla/dom/CanvasRenderingContextHelper.h"
+#include "mozilla/gfx/Point.h"
+#include "mozilla/layers/LayersTypes.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/Mutex.h"
+#include "mozilla/RefPtr.h"
+#include "nsISupportsImpl.h"
+#include "nsThreadUtils.h"
+
+namespace mozilla::dom {
+class HTMLCanvasElement;
+class OffscreenCanvas;
+class ThreadSafeWorkerRef;
+
+struct OffscreenCanvasDisplayData final {
+  mozilla::gfx::IntSize mSize = {0, 0};
+  bool mDoPaintCallbacks = false;
+  bool mIsOpaque = true;
+  bool mIsAlphaPremult = true;
+  mozilla::gl::OriginPos mOriginPos = gl::OriginPos::TopLeft;
+  Maybe<layers::RemoteTextureOwnerId> mOwnerId;
+};
+
+class OffscreenCanvasDisplayHelper final {
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(OffscreenCanvasDisplayHelper)
+
+ public:
+  explicit OffscreenCanvasDisplayHelper(HTMLCanvasElement* aCanvasElement,
+                                        uint32_t aWidth, uint32_t aHeight);
+
+  CanvasContextType GetContextType() const;
+
+  RefPtr<layers::ImageContainer> GetImageContainer() const;
+
+  void UpdateContext(OffscreenCanvas* aOffscreenCanvas,
+                     RefPtr<ThreadSafeWorkerRef>&& aWorkerRef,
+                     CanvasContextType aType, const Maybe<int32_t>& aChildId);
+
+  void FlushForDisplay();
+
+  bool CommitFrameToCompositor(nsICanvasRenderingContextInternal* aContext,
+                               layers::TextureType aTextureType,
+                               const Maybe<OffscreenCanvasDisplayData>& aData);
+
+  void DestroyCanvas();
+  void DestroyElement();
+
+  already_AddRefed<mozilla::gfx::SourceSurface> GetSurfaceSnapshot();
+  already_AddRefed<mozilla::layers::Image> GetAsImage();
+
+ private:
+  ~OffscreenCanvasDisplayHelper();
+  void MaybeQueueInvalidateElement() MOZ_REQUIRES(mMutex);
+  void InvalidateElement();
+
+  bool TransformSurface(const gfx::DataSourceSurface::ScopedMap& aSrcMap,
+                        const gfx::DataSourceSurface::ScopedMap& aDstMap,
+                        gfx::SurfaceFormat aFormat, const gfx::IntSize& aSize,
+                        bool aNeedsPremult, gl::OriginPos aOriginPos) const;
+
+  mutable Mutex mMutex;
+  HTMLCanvasElement* MOZ_NON_OWNING_REF mCanvasElement MOZ_GUARDED_BY(mMutex);
+  OffscreenCanvas* MOZ_NON_OWNING_REF mOffscreenCanvas MOZ_GUARDED_BY(mMutex) =
+      nullptr;
+  RefPtr<layers::ImageContainer> mImageContainer MOZ_GUARDED_BY(mMutex);
+  RefPtr<gfx::SourceSurface> mFrontBufferSurface MOZ_GUARDED_BY(mMutex);
+  RefPtr<ThreadSafeWorkerRef> mWorkerRef MOZ_GUARDED_BY(mMutex);
+
+  OffscreenCanvasDisplayData mData MOZ_GUARDED_BY(mMutex);
+  CanvasContextType mType MOZ_GUARDED_BY(mMutex) = CanvasContextType::NoContext;
+  Maybe<uint32_t> mContextManagerId MOZ_GUARDED_BY(mMutex);
+  Maybe<int32_t> mContextChildId MOZ_GUARDED_BY(mMutex);
+  const mozilla::layers::ImageContainer::ProducerID mImageProducerID;
+  mozilla::layers::ImageContainer::FrameID mLastFrameID MOZ_GUARDED_BY(mMutex) =
+      0;
+  bool mPendingInvalidate MOZ_GUARDED_BY(mMutex) = false;
+};
+
+}  // namespace mozilla::dom
+
+#endif  // MOZILLA_DOM_OFFSCREENCANVASDISPLAYHELPER_H_