--- a/gfx/layers/GLImages.h
+++ b/gfx/layers/GLImages.h
@@ -44,16 +44,22 @@ public:
   }
   bool GetContinuous() const {
     return mContinuous;
   }
   gl::OriginPos GetOriginPos() const {
     return mOriginPos;
   }
 
+  virtual already_AddRefed<gfx::SourceSurface> GetAsSourceSurface() override {
+    // We can implement this, but currently don't want to because it will cause the
+    // SurfaceTexture to be permanently bound to the snapshot readback context.
+    return nullptr;
+  }
+
   SurfaceTextureImage* AsSurfaceTextureImage() override {
     return this;
   }
 
 private:
   AndroidSurfaceTextureHandle mHandle;
   gfx::IntSize mSize;
   bool mContinuous;