diff --git a/mozilla/content/html/style/src/nsCSSStruct.cpp b/mozilla/content/html/style/src/nsCSSStruct.cpp
index ece41ed3734..98ab3f4afda 100644
--- a/mozilla/content/html/style/src/nsCSSStruct.cpp
+++ b/mozilla/content/html/style/src/nsCSSStruct.cpp
@@ -482,6 +482,7 @@ nsCSSDisplay::nsCSSDisplay(const nsCSSDisplay& aCopy)
   : mDirection(aCopy.mDirection),
     mDisplay(aCopy.mDisplay),
     mBinding(aCopy.mBinding),
+    mAppearance(aCopy.mAppearance),
     mPosition(aCopy.mPosition),
     mFloat(aCopy.mFloat),
     mClear(aCopy.mClear),
diff --git a/mozilla/layout/style/nsCSSStruct.cpp b/mozilla/layout/style/nsCSSStruct.cpp
index ece41ed3734..98ab3f4afda 100644
--- a/mozilla/layout/style/nsCSSStruct.cpp
+++ b/mozilla/layout/style/nsCSSStruct.cpp
@@ -482,6 +482,7 @@ nsCSSDisplay::nsCSSDisplay(const nsCSSDisplay& aCopy)
   : mDirection(aCopy.mDirection),
     mDisplay(aCopy.mDisplay),
     mBinding(aCopy.mBinding),
+    mAppearance(aCopy.mAppearance),
     mPosition(aCopy.mPosition),
     mFloat(aCopy.mFloat),
     mClear(aCopy.mClear),