diff --git a/gfx/layers/ImageContainer.cpp b/gfx/layers/ImageContainer.cpp
index 901ced77a29..a243e651089 100644
--- a/gfx/layers/ImageContainer.cpp
+++ b/gfx/layers/ImageContainer.cpp
@@ -794,10 +794,11 @@ nsresult PlanarYCbCrImage::BuildSurfaceDescriptorBuffer(
 
     // If we can copy directly from the surface, let's do that to avoid the YUV
     // to RGB conversion.
-    if (mSourceSurface && mSourceSurface->GetSize() == size) {
-      DataSourceSurface::ScopedMap map(mSourceSurface, DataSourceSurface::READ);
+    RefPtr<gfx::DataSourceSurface> sourceSurface = mSourceSurface.Get();
+    if (sourceSurface && sourceSurface->GetSize() == size) {
+      DataSourceSurface::ScopedMap map(sourceSurface, DataSourceSurface::READ);
       if (map.IsMapped() && SwizzleData(map.GetData(), map.GetStride(),
-                                        mSourceSurface->GetFormat(), buffer,
+                                        sourceSurface->GetFormat(), buffer,
                                         stride, format, size)) {
         return NS_OK;
       }
@@ -987,9 +988,8 @@ nsresult PlanarYCbCrImage::AdoptData(const Data& aData) {
 }
 
 already_AddRefed<gfx::SourceSurface> PlanarYCbCrImage::GetAsSourceSurface() {
-  if (mSourceSurface) {
-    RefPtr<gfx::SourceSurface> surface(mSourceSurface);
-    return surface.forget();
+  if (RefPtr<gfx::DataSourceSurface> cached = mSourceSurface.Get()) {
+    return cached.forget();
   }
 
   gfx::IntSize size(mSize);
@@ -1019,30 +1019,24 @@ already_AddRefed<gfx::SourceSurface> PlanarYCbCrImage::GetAsSourceSurface() {
     return nullptr;
   }
 
-  mSourceSurface = surface;
+  mSourceSurface.Set(surface);
 
   return surface.forget();
 }
 
-PlanarYCbCrImage::~PlanarYCbCrImage() {
-  NS_ReleaseOnMainThread("PlanarYCbCrImage::mSourceSurface",
-                         mSourceSurface.forget());
-}
+PlanarYCbCrImage::~PlanarYCbCrImage() = default;
 
 NVImage::NVImage() : Image(nullptr, ImageFormat::NV_IMAGE), mBufferSize(0) {}
 
-NVImage::~NVImage() {
-  NS_ReleaseOnMainThread("NVImage::mSourceSurface", mSourceSurface.forget());
-}
+NVImage::~NVImage() = default;
 
 IntSize NVImage::GetSize() const { return mSize; }
 
 IntRect NVImage::GetPictureRect() const { return mData.mPictureRect; }
 
 already_AddRefed<SourceSurface> NVImage::GetAsSourceSurface() {
-  if (mSourceSurface) {
-    RefPtr<gfx::SourceSurface> surface(mSourceSurface);
-    return surface.forget();
+  if (RefPtr<gfx::DataSourceSurface> cached = mSourceSurface.Get()) {
+    return cached.forget();
   }
 
   // Convert the current NV12 or NV21 data to YUV420P so that we can follow the
@@ -1100,7 +1094,7 @@ already_AddRefed<SourceSurface> NVImage::GetAsSourceSurface() {
     return nullptr;
   }
 
-  mSourceSurface = surface;
+  mSourceSurface.Set(surface);
 
   return surface.forget();
 }
@@ -1122,7 +1116,8 @@ nsresult NVImage::BuildSurfaceDescriptorBuffer(
 
   UniquePtr<uint8_t[]> buffer;
 
-  if (!mSourceSurface) {
+  RefPtr<gfx::DataSourceSurface> sourceSurface = mSourceSurface.Get();
+  if (!sourceSurface) {
     const int bufferLength =
         ySize.height * mData.mYStride + cbcrSize.height * cbcrSize.width * 2;
     buffer = MakeUnique<uint8_t[]>(bufferLength);
@@ -1152,7 +1147,7 @@ nsresult NVImage::BuildSurfaceDescriptorBuffer(
     return NS_ERROR_FAILURE;
   }
 
-  if (mSourceSurface && mSourceSurface->GetSize() != size) {
+  if (sourceSurface && sourceSurface->GetSize() != size) {
     return NS_ERROR_NOT_IMPLEMENTED;
   }
 
@@ -1164,7 +1159,7 @@ nsresult NVImage::BuildSurfaceDescriptorBuffer(
     return rv;
   }
 
-  if (!mSourceSurface) {
+  if (!sourceSurface) {
     rv = gfx::ConvertYCbCrToRGB(aData, format, size, output, stride);
     if (NS_WARN_IF(NS_FAILED(rv))) {
       MOZ_ASSERT_UNREACHABLE("Failed to convert YUV into RGB data");
@@ -1173,12 +1168,12 @@ nsresult NVImage::BuildSurfaceDescriptorBuffer(
     return NS_OK;
   }
 
-  DataSourceSurface::ScopedMap map(mSourceSurface, DataSourceSurface::WRITE);
+  DataSourceSurface::ScopedMap map(sourceSurface, DataSourceSurface::WRITE);
   if (NS_WARN_IF(!map.IsMapped())) {
     return NS_ERROR_FAILURE;
   }
 
-  if (!SwizzleData(map.GetData(), map.GetStride(), mSourceSurface->GetFormat(),
+  if (!SwizzleData(map.GetData(), map.GetStride(), sourceSurface->GetFormat(),
                    output, stride, format, size)) {
     return NS_ERROR_FAILURE;
   }
diff --git a/gfx/layers/ImageContainer.h b/gfx/layers/ImageContainer.h
index 0fe66df2a34..952fe1a3c60 100644
--- a/gfx/layers/ImageContainer.h
+++ b/gfx/layers/ImageContainer.h
@@ -9,6 +9,7 @@
 #include "ImageTypes.h"  // for ImageFormat, etc
 #include "mozilla/AlreadyAddRefed.h"
 #include "mozilla/Assertions.h"      // for MOZ_ASSERT_HELPER2
+#include "mozilla/DataMutex.h"       // for DataMutex
 #include "mozilla/Mutex.h"           // for Mutex
 #include "mozilla/RecursiveMutex.h"  // for RecursiveMutex, etc
 #include "mozilla/ThreadSafeWeakPtr.h"
@@ -24,6 +25,7 @@
 #include "nsISupportsImpl.h"  // for Image::Release, etc
 #include "nsTArray.h"         // for nsTArray
 #include "nsThreadUtils.h"    // for NS_IsMainThread
+#include "nsProxyRelease.h"   // for NS_ReleaseOnMainThread
 #include "mozilla/Atomics.h"
 #include "mozilla/gfx/2D.h"
 #include "mozilla/EnumeratedArray.h"
@@ -219,6 +221,46 @@ class Image {
   static mozilla::Atomic<int32_t> sSerialCounter;
 };
 
+/**
+ * A thread-safe, lazily-populated cache of an Image's rasterized surface.
+ */
+class CachedSurface final {
+ public:
+  CachedSurface() : mSurface("layers::CachedSurface") {}
+
+  ~CachedSurface() {
+    // The surface may have been created off the main thread, but like the rest
+    // of the gfx surface machinery it must be released on the main thread.
+    RefPtr<gfx::DataSourceSurface> surface;
+    {
+      auto guard = mSurface.Lock();
+      surface = guard->forget();
+    }
+    NS_ReleaseOnMainThread("layers::CachedSurface", surface.forget());
+  }
+
+  // Returns the cached surface, or nullptr if nothing has been cached yet.
+  already_AddRefed<gfx::DataSourceSurface> Get() {
+    auto guard = mSurface.Lock();
+    RefPtr<gfx::DataSourceSurface> surface = *guard;
+    return surface.forget();
+  }
+
+  // Stores aSurface unless another thread has already cached one. The caller
+  // may keep using its own surface regardless: both are equivalent
+  // rasterizations of the same image, and keeping the first one avoids dropping
+  // a surface that a concurrent caller may already have handed out.
+  void Set(gfx::DataSourceSurface* aSurface) {
+    auto guard = mSurface.Lock();
+    if (!*guard) {
+      *guard = aSurface;
+    }
+  }
+
+ private:
+  mozilla::DataMutex<RefPtr<gfx::DataSourceSurface>> mSurface;
+};
+
 MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Image::BuildSdbFlags)
 
 /**
@@ -915,7 +957,7 @@ class PlanarYCbCrImage : public Image {
   gfx::IntSize mSize;
   gfx::ColorDepth mColorDepth = gfx::ColorDepth::COLOR_8;
   gfxImageFormat mOffscreenFormat;
-  RefPtr<gfx::DataSourceSurface> mSourceSurface;
+  CachedSurface mSourceSurface;
   uint32_t mBufferSize;
 };
 
@@ -978,7 +1020,7 @@ class NVImage final : public Image {
   uint32_t mBufferSize;
   gfx::IntSize mSize;
   Data mData;
-  RefPtr<gfx::DataSourceSurface> mSourceSurface;