diff --git a/gfx/layers/client/CompositableClient.cpp b/gfx/layers/client/CompositableClient.cpp
index 2a4a6ef7dff..cc4cfc86100 100644
--- a/gfx/layers/client/CompositableClient.cpp
+++ b/gfx/layers/client/CompositableClient.cpp
@@ -207,7 +207,8 @@ CompositableClient::CreateTextureClientForDrawing(SurfaceFormat aFormat,
   if (parentBackend == LayersBackend::LAYERS_D3D9 &&
       !GetForwarder()->ForwardsToDifferentProcess() &&
       !(aTextureFlags & TEXTURE_ALLOC_FALLBACK)) {
-    if (!gfxWindowsPlatform::GetPlatform()->GetD3D9Device()) {
+    // non-DIB textures don't work with alpha, see notes in TextureD3D9.
+    if (ContentForFormat(aFormat) != gfxContentType::COLOR) {
       result = new DIBTextureClientD3D9(aFormat, aTextureFlags);
     } else {
       result = new CairoTextureClientD3D9(aFormat, aTextureFlags);
diff --git a/gfx/layers/client/ContentClient.cpp b/gfx/layers/client/ContentClient.cpp
index f28ff3b5ade..132e0f8bc63 100644
--- a/gfx/layers/client/ContentClient.cpp
+++ b/gfx/layers/client/ContentClient.cpp
@@ -63,8 +63,7 @@ ContentClient::CreateContentClient(CompositableForwarder* aForwarder)
   } else
 #endif
   {
-    useDoubleBuffering = (LayerManagerComposite::SupportsDirectTexturing() &&
-                         backend != LayersBackend::LAYERS_D3D9) ||
+    useDoubleBuffering = LayerManagerComposite::SupportsDirectTexturing() ||
                          backend == LayersBackend::LAYERS_BASIC;
   }
 
diff --git a/gfx/layers/d3d9/TextureD3D9.cpp b/gfx/layers/d3d9/TextureD3D9.cpp
index 18d3f477552..b01cd07c5cb 100644
--- a/gfx/layers/d3d9/TextureD3D9.cpp
+++ b/gfx/layers/d3d9/TextureD3D9.cpp
@@ -1258,7 +1258,6 @@ CairoTextureClientD3D9::CairoTextureClientD3D9(gfx::SurfaceFormat aFormat, Textu
   , mFormat(aFormat)
   , mIsLocked(false)
   , mNeedsClear(false)
-  , mLockRect(false)
 {
   MOZ_COUNT_CTOR(CairoTextureClientD3D9);
 }
@@ -1292,11 +1291,6 @@ CairoTextureClientD3D9::Unlock()
     mDrawTarget = nullptr;
   }
 
-  if (mLockRect) {
-    mD3D9Surface->UnlockRect();
-    mLockRect = false;
-  }
-
   if (mSurface) {
     mSurface = nullptr;
   }
@@ -1339,19 +1333,11 @@ CairoTextureClientD3D9::GetAsDrawTarget()
     }
   }
 
-  if (ContentForFormat(mFormat) == gfxContentType::COLOR_ALPHA) {
-    D3DLOCKED_RECT rect;
-    mD3D9Surface->LockRect(&rect, nullptr, 0);
-    mSurface = new gfxImageSurface((uint8_t*)rect.pBits, ThebesIntSize(mSize),
-                                   rect.Pitch, gfxImageFormat::ARGB32);
-    mLockRect = true;
-  } else {
-    mSurface = new gfxWindowsSurface(mD3D9Surface);
-    if (!mSurface || mSurface->CairoStatus()) {
-      NS_WARNING("Could not create surface for d3d9 surface");
-      mSurface = nullptr;
-      return nullptr;
-    }
+  mSurface = new gfxWindowsSurface(mD3D9Surface);
+  if (!mSurface || mSurface->CairoStatus()) {
+    NS_WARNING("Could not create surface for d3d9 surface");
+    mSurface = nullptr;
+    return nullptr;
   }
 
   mDrawTarget =
diff --git a/gfx/layers/d3d9/TextureD3D9.h b/gfx/layers/d3d9/TextureD3D9.h
index 5007176065f..e4c9c962f12 100644
--- a/gfx/layers/d3d9/TextureD3D9.h
+++ b/gfx/layers/d3d9/TextureD3D9.h
@@ -181,7 +181,7 @@ protected:
 };
 
 /**
- * Can only be drawn into through Cairo and need a D3D9 context on the client side.
+ * Can only be drawn into through Cairo, and only support opaque surfaces.
  * The corresponding TextureHost is TextureHostD3D9.
  */
 class CairoTextureClientD3D9 : public TextureClient
@@ -228,12 +228,11 @@ private:
   gfx::SurfaceFormat mFormat;
   bool mIsLocked;
   bool mNeedsClear;
-  bool mLockRect;
 };
 
 /**
  * Can only be drawn into through Cairo.
- * Prefer CairoTextureClientD3D9 when possible.
+ * Supports opaque surfaces. Prefer CairoTextureClientD3D9 when possible.
  * The coresponding TextureHost is DIBTextureHostD3D9.
  */
 class DIBTextureClientD3D9 : public TextureClient