Error after dhtmlXComboFromSelect function

We tried using the function dhtmlXComboFromSelect on a select input created with dhxForm. However; when we try to use a function in the combobox eg. ComboBox.clearAll(true), we get an error in dhtmlx.js: “‘parentNode.parentNode’ is null or not an object” in line 3578


please provide a demo to recreate the problem locally


Please check attached demo.
Note, this is demo only, not a fact the suggested code 100% will used in future releases. (40.7 KB)