Combobox item selection rely items label string

Sometimes is needed to add multiple items with same label, but there can be different icon and/or description. Current version has bug at server and client.

Bugs, when combobox has multiple items which has identical labels:
-client: change is not triggered when select another item with same label
-server: combobox's selected item is find by string, not by item. Selected item is first Comboitem, which label match.

Combobox need rely on items, not strings, when selecting item(s).