private void OnDrawElement(Rect rect, int index, bool isActive, bool isFocused)
{
SerializedProperty element = base.serializedProperty.GetArrayElementAtIndex(index);
rect.x += 10;
rect.y += 2;
rect.width -= 10;
string key = element.FindPropertyRelative("key").stringValue;
bool isOverride = _library.IsOverride(key);
string label = isOverride ? string.Concat(key, " [Override]") : key;
EditorGUI.PropertyField(rect, element, new GUIContent(label), true);
}