diff --git a/examples/window.cpp b/examples/window.cpp
--- a/examples/window.cpp
+++ b/examples/window.cpp
@@ -122,20 +122,29 @@
         m_set.addProperty(new KProperty("DateTime", QDateTime::currentDateTime(), "Date/Time"), group);
     }
 
-    QStringList name_list({"My Item", "Other Item", "Third Item"}); //strings
+    QStringList name_list({"First Item", "Second Item", "Third Item"}); //strings
     if (singleProperty.isEmpty() || singleProperty=="List") {
-        const QStringList keys({"myitem", "otheritem", "3rditem"});
+        const QStringList keys({"1stitem", "2nditem", "3rditem"});
         KPropertyListData *listData = new KPropertyListData(keys, name_list);
-        m_set.addProperty(new KProperty("List", listData, "otheritem", "List"), group);
+        m_set.addProperty(new KProperty("List", listData, QVariant(keys[1]), "List"), group);
     }
 
+    QVariantList list_keys({1, 2, 3});
     if (singleProperty.isEmpty() || singleProperty=="List2") {
         // A valueFromList property matching strings with ints (could be any type supported by QVariant)
-        QVariantList keys({1, 2, 3});
         KPropertyListData *listData = new KPropertyListData;
-        listData->setKeys(keys);
+        listData->setKeys(list_keys);
         listData->setNamesAsStringList(name_list);
-        m_set.addProperty(new KProperty("List2", listData, 3, "List 2"), group);
+        m_set.addProperty(new KProperty("List2", listData, list_keys.last(), "List 2"), group);
+    }
+    if (singleProperty.isEmpty() || singleProperty=="EditableList") {
+        // A valueFromList property matching strings with ints (could be any type supported by QVariant)
+        KPropertyListData *listData = new KPropertyListData;
+        listData->setKeys(list_keys);
+        listData->setNamesAsStringList(name_list);
+        p = new KProperty("EditableList", listData, list_keys.first(), "Editable List");
+        p->setOption("extraValueAllowed", true);
+        m_set.addProperty(p, group);
     }
 
 //  Complex
diff --git a/src/editors/combobox.cpp b/src/editors/combobox.cpp
--- a/src/editors/combobox.cpp
+++ b/src/editors/combobox.cpp
@@ -67,9 +67,14 @@
     Private()
     {
     }
+    ~Private()
+    {
+        delete completer;
+    }
     KPropertyListData listData;
     bool setValueEnabled = true;
     KPropertyComboBoxEditorOptions options;
+    QCompleter *completer = nullptr;
 };
 
 KPropertyComboBoxEditor::KPropertyComboBoxEditor(const KPropertyListData &listData,
@@ -123,11 +128,7 @@
 
 bool KPropertyComboBoxEditor::listDataKeysAvailable() const
 {
-    if (d->listData.keys().isEmpty()) {
-        kprWarning() << "property listData not available!";
-        return false;
-    }
-    return true;
+    return !d->listData.keys().isEmpty();
 }
 
 QVariant KPropertyComboBoxEditor::value() const
@@ -148,9 +149,6 @@
 
 void KPropertyComboBoxEditor::setValue(const QVariant &value)
 {
-    if (!listDataKeysAvailable())
-        return;
-
     if (!d->setValueEnabled)
         return;
     const int idx = d->listData.keys().isEmpty() ? -1 : d->listData.keys().indexOf(value);
@@ -181,6 +179,7 @@
 
 void KPropertyComboBoxEditor::fillValues()
 {
+    delete d->completer;
     clear();
     if (!listDataKeysAvailable())
         return;
@@ -194,8 +193,10 @@
         }
         index++;
     }
-    QCompleter *comp = new QCompleter(d->listData.namesAsStringList());
-    comp->setWidget(this);
+    if (isEditable()) {
+        d->completer = new QCompleter(d->listData.namesAsStringList());
+        d->completer->setWidget(this);
+    }
 }
 
 void KPropertyComboBoxEditor::setListData(const KPropertyListData & listData)