diff --git a/src/item_group.cpp b/src/item_group.cpp
index ddfaa377a1ae1..10bb167b12919 100644
--- a/src/item_group.cpp
+++ b/src/item_group.cpp
@@ -378,6 +378,7 @@ void Item_modifier::modify( item &new_item ) const
 
     if( !cont.is_null() ) {
         cont.put_in( new_item, item_pocket::pocket_type::CONTAINER );
+        cont.seal();
         new_item = cont;
     }
 
@@ -386,6 +387,7 @@ void Item_modifier::modify( item &new_item ) const
         for( const item &it : contentitems ) {
             new_item.put_in( it, item_pocket::pocket_type::CONTAINER );
         }
+        new_item.seal();
     }
 
     for( auto &flag : custom_flags ) {
diff --git a/src/item_pocket.cpp b/src/item_pocket.cpp
index af3f0d59c0f7a..f248ff08fb57a 100644
--- a/src/item_pocket.cpp
+++ b/src/item_pocket.cpp
@@ -1129,7 +1129,7 @@ void item_pocket::on_pickup( Character &guy )
 
 void item_pocket::on_contents_changed()
 {
-    _sealed = false;
+    unseal();
     restack();
 }