diff --git a/taglib/toolkit/tbytevectorlist.cpp b/taglib/toolkit/tbytevectorlist.cpp
index 8171781d..0088087f 100644
--- a/taglib/toolkit/tbytevectorlist.cpp
+++ b/taglib/toolkit/tbytevectorlist.cpp
@@ -70,6 +70,7 @@ ByteVectorList::~ByteVectorList() = default;
 ByteVectorList::ByteVectorList(const ByteVectorList &l) :
   List<ByteVector>(l)
 {
+  *d = *l.d;
 }
 
 ByteVectorList::ByteVectorList(std::initializer_list<ByteVector> init) :
@@ -83,6 +84,7 @@ ByteVectorList &ByteVectorList::operator=(const ByteVectorList &l)
     return *this;
 
   List<ByteVector>::operator=(l);
+  *d = *l.d;
   return *this;
 }
 
diff --git a/taglib/toolkit/tstringlist.cpp b/taglib/toolkit/tstringlist.cpp
index 224afc2c..aa6acf64 100644
--- a/taglib/toolkit/tstringlist.cpp
+++ b/taglib/toolkit/tstringlist.cpp
@@ -59,6 +59,7 @@ StringList::StringList() = default;
 StringList::StringList(const StringList &l) :
   List<String>(l)
 {
+  *d = *l.d;
 }
 
 StringList::StringList(std::initializer_list<String> init) :
@@ -72,6 +73,7 @@ StringList &StringList::operator=(const StringList &l)
     return *this;
 
   List<String>::operator=(l);
+  *d = *l.d;
   return *this;
 }