diff --git a/layout/base/nsDisplayList.h b/layout/base/nsDisplayList.h
index 023c0248aaed..99ecd69c1b2e 100644
--- a/layout/base/nsDisplayList.h
+++ b/layout/base/nsDisplayList.h
@@ -2186,8 +2186,6 @@ private:
   nsDisplayItemLink  mSentinel;
   nsDisplayItemLink* mTop;
 
-  // This is set by ComputeVisibility
-  nsRect mVisibleRect;
   // This is set to true by FrameLayerBuilder if the final visible region
   // is empty (i.e. everything that was visible is covered by some
   // opaque content in this list).