--- a/layout/base/FrameLayerBuilder.cpp
+++ b/layout/base/FrameLayerBuilder.cpp
@@ -4224,27 +4224,23 @@ FrameLayerBuilder::DrawThebesLayer(Thebe
 
     DrawForcedBackgroundColor(aContext, aLayer, userData->mForcedBackgroundColor);
   }
 
   // make the origin of the context coincide with the origin of the
   // ThebesLayer
   gfxContextMatrixAutoSaveRestore saveMatrix(aContext);
   nsIntPoint offset = GetTranslationForThebesLayer(aLayer);
+
   nsPresContext* presContext = entry->mContainerLayerFrame->PresContext();
-
-  if (!layerBuilder->GetContainingThebesLayerData()) {
-    // Recompute visibility of items in our ThebesLayer. Note that this
-    // recomputes visibility for all descendants of our display items too,
-    // so there's no need to do this for the items in inactive ThebesLayers.
-    int32_t appUnitsPerDevPixel = presContext->AppUnitsPerDevPixel();
-    RecomputeVisibilityForItems(entry->mItems, builder, aRegionToDraw,
-                                offset, appUnitsPerDevPixel,
-                                userData->mXScale, userData->mYScale);
-  }
+  int32_t appUnitsPerDevPixel = presContext->AppUnitsPerDevPixel();
+
+  RecomputeVisibilityForItems(entry->mItems, builder, aRegionToDraw,
+                              offset, appUnitsPerDevPixel,
+                              userData->mXScale, userData->mYScale);
 
   nsRefPtr<nsRenderingContext> rc = new nsRenderingContext();
   rc->Init(presContext->DeviceContext(), aContext);
 
   if (shouldDrawRectsSeparately) {
     nsIntRegionRectIterator it(aRegionToDraw);
     while (const nsIntRect* iterRect = it.Next()) {
       gfxContextAutoSaveRestore save(aContext);